Ecosystems on the verge of major reorganization—regime shift—may exhibit declining resilience, which can be detected using a collection of generic statistical tests known as early warning signals ...(EWSs). This study explores whether EWSs anticipated human population collapse during the European Neolithic. It analyzes recent reconstructions of European Neolithic (8–4 kya) population trends that reveal regime shifts from a period of rapid growth following the introduction of agriculture to a period of instability and collapse. We find statistical support for EWSs in advance of population collapse. Seven of nine regional datasets exhibit increasing autocorrelation and variance leading up to collapse, suggesting that these societies began to recover from perturbation more slowly as resilience declined. We derive EWS statistics from a prehistoric population proxy based on summed archaeological radiocarbon date probability densities. We use simulation to validate our methods and show that sampling biases, atmospheric effects, radiocarbon calibration error, and taphonomic processes are unlikely to explain the observed EWS patterns. The implications of these results for understanding the dynamics of Neolithic ecosystems are discussed, and we present a general framework for analyzing societal regime shifts using EWS at large spatial and temporal scales. We suggest that our findings are consistent with an adaptive cycling model that highlights both the vulnerability and resilience of early European populations. We close by discussing the implications of the detection of EWS in human systems for archaeology and sustainability science.
The late pre-Hispanic period in the US Southwest (A.D. 1200–1450) was characterized by large-scale demographic changes, including long-distance migration and population aggregation. To reconstruct ...how these processes reshaped social networks, we compiled a comprehensive artifact database from major sites dating to this interval in the western Southwest. We combine social network analysis with geographic information systems approaches to reconstruct network dynamics over 250 y. We show how social networks were transformed across the region at previously undocumented spatial, temporal, and social scales. Using well-dated decorated ceramics, we track changes in network topology at 50-y intervals to show a dramatic shift in network density and settlement centrality from the northern to the southern Southwest after A.D. 1300. Both obsidian sourcing and ceramic data demonstrate that long-distance network relationships also shifted from north to south after migration. Surprisingly, social distance does not always correlate with spatial distance because of the presence of network relationships spanning long geographic distances. Our research shows how a large network in the southern Southwest grew and then collapsed, whereas networks became more fragmented in the northern Southwest but persisted. The study also illustrates how formal social network analysis may be applied to large-scale databases of material culture to illustrate multigenerational changes in network structure.
Human leukocyte antigen B (HLA‐B) is responsible for presenting peptides to immune cells and plays a critical role in normal immune recognition of pathogens. A variant allele, HLA‐B*57:01, is ...associated with increased risk of a hypersensitivity reaction to the anti‐HIV drug abacavir. In the absence of genetic prescreening, hypersensitivity affects ~6% of patients and can be life‐threatening with repeated dosing. We provide recommendations (updated periodically at http://www.pharmkgb.org) for the use of abacavir based on HLA‐B genotype.
Clinical Pharmacology & Therapeutics (2012); 91 4, 734–738. doi:10.1038/clpt.2011.355
Current models of the peopling of the higher-elevation zones of the Tibetan Plateau postulate that permanent occupation could only have been facilitated by an agricultural lifeway at ~3.6 thousand ...calibrated carbon-14 years before present. Here we report a reanalysis of the chronology of the Chusang site, located on the central Tibetan Plateau at an elevation of ~4270 meters above sea level. The minimum age of the site is fixed at ~7.4 thousand years (thorium-230/uranium dating), with a maximum age between ~8.20 and 12.67 thousand calibrated carbon-14 years before present (carbon-14 assays). Travel cost modeling and archaeological data suggest that the site was part of an annual, permanent, preagricultural occupation of the central plateau. These findings challenge current models of the occupation of the Tibetan Plateau.
The HIV type‐1 nonnucleoside reverse transcriptase inhibitor, efavirenz, is widely used to treat HIV type‐1 infection. Efavirenz is predominantly metabolized into inactive metabolites by cytochrome ...P450 (CYP)2B6, and patients with certain CYP2B6 genetic variants may be at increased risk for adverse effects, particularly central nervous system toxicity and treatment discontinuation. We summarize the evidence from the literature and provide therapeutic recommendations for efavirenz prescribing based on CYP2B6 genotypes.
Tuberculosis is an ancient human disease, estimated to have originated and evolved over thousands of years alongside modern human populations. Despite considerable advances in disease control, ...tuberculosis remains one of the world's deadliest communicable diseases with 10 million incident cases and 1·8 million deaths in 2015 alone based on the annual WHO report, due to inadequate health service resources in less-developed regions of the world, and exacerbated by the HIV/AIDS pandemic and emergence of multidrug-resistant strains of Mycobacterium tuberculosis. Recent findings from studies of tuberculosis infection and of patients with Mendelian predisposition to severe tuberculosis have started to reveal human loci influencing tuberculosis outcomes. In this Review, we assess the current understanding of the contribution of host genetics to disease susceptibility and to drug treatment. Despite remarkable progress in technology, only a few associated genetic variants have so far been identified, strongly indicating the need for larger global studies that investigate both common and under-represented rare variants to develop new approaches to combat the disease. Pharmacogenomic discoveries are also likely to lead to more efficient drug design and development, and ultimately safer and more effective therapies for tuberculosis.
Empathy is an important human ability associated with successful social interaction. It is currently unclear how to optimally measure individual differences in empathic processing. Although the Big ...Five model of personality is an effective model to explain individual differences in human experience and behavior, its relation to measures of empathy is currently not well understood. Therefore, the present study was designed to investigate the relationship between the Big Five personality concept and two commonly used measures for empathy Empathy Quotient (EQ), Interpersonal Reactivity Index (IRI) in four samples from China, Germany, Spain, and the United States of America. This approach was designed to advance the way the Big Five personality model can be used to measure empathy. We found evidence of medium effect sizes for associations between personality and empathy, with agreeableness and conscientiousness as the most important predictors of affective and cognitive empathy (measured by the respective IRI subscales) as well as for a one-dimensional empathy score (measured by the EQ). Empathy in a fictional context was most closely related to openness to experience while personal distress was first of all related to neuroticism. In terms of culture, we did not observe any distinct pattern concerning cultural differences. These results support the cross-cultural applicability of the EQ and the IRI and indicate structurally similar associations between personality and empathy across cultures.
Background
Hiatal Hernia (HH) is a common structural defect of the diaphragm. Laparoscopic repair with suturing of the hiatal pillars followed by fundoplication has become standard practice. In an ...attempt to lower HH recurrence rates, mesh reinforcement, commonly located at the posterior site of the esophageal hiatus, has been used. However, effectiveness of posterior mesh augmentation is still up to debate. There is a lack of understanding of the mechanism of recurrence requiring further investigation. We investigated the anatomic location of HH recurrences in an attempt to assess why HH recurrence rates remain high despite various attempts with mesh reinforcement.
Methods
A retrospective case series of prospectively collected data from patients with hiatal hernia repair between 2012 and 2020 was performed. In total, 54 patients with a recurrent hiatal hernia operation were included in the study. Video clips from the revision procedure were analyzed by a surgical registrar and senior surgeon to assess the anatomic location of recurrent HH. For the assessment, the esophageal hiatus was divided into four equal quadrants. Additionally, patient demographics, hiatal hernia characteristics, and operation details were collected and analyzed.
Results
54 patients were included. The median time between primary repair and revision procedure was 25 months (IQR 13–95, range 0–250). The left-anterior quadrant was involved in 43 patients (80%), the right-anterior quadrant in 21 patients (39%), the left-posterior quadrant in 21 patients (39%), and the right-posterior quadrant in 10 patients (19%).
Conclusion
In this study, hiatal hernia recurrences occured most commonly at the left-anterior quadrant of the hiatus, however, posterior recurrences were not uncommon. Based on our results, we hypothesize that both posterior and anterior hiatal reinforcement might be a suitable solution to lower the recurrence rate of hiatal hernia. A randomized controlled trial using a circular, bio-absorbable mesh has been initiated to test our hypothesis.
Settlement size predicts extreme variation in the rates and magnitudes of many social and ecological processes in human societies. Yet, the factors that drive human settlement-size variation remain ...poorly understood. Size variation among economically integrated settlements tends to be heavy tailed such that the smallest settlements are extremely common and the largest settlements extremely large and rare. The upper tail of this size distribution is often formalized mathematically as a power-law function. Explanations for this scaling structure in human settlement systems tend to emphasize complex socioeconomic processes including agriculture, manufacturing, and warfare-behaviors that tend to differentially nucleate and disperse populations hierarchically among settlements. But, the degree to which heavy-tailed settlement-size variation requires such complex behaviors remains unclear. By examining the settlement patterns of eight prehistoric New World hunter-gatherer settlement systems spanning three distinct environmental contexts, this analysis explores the degree to which heavy-tailed settlement-size scaling depends on the aforementioned socioeconomic complexities. Surprisingly, the analysis finds that power-law models offer plausible and parsimonious statistical descriptions of prehistoric hunter-gatherer settlement-size variation. This finding reveals that incipient forms of hierarchical settlement structure may have preceded socioeconomic complexity in human societies and points to a need for additional research to explicate how mobile foragers came to exhibit settlement patterns that are more commonly associated with hierarchical organization. We propose that hunter-gatherer mobility with preferential attachment to previously occupied locations may account for the observed structure in site-size variation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The metabolic effects of initial therapy for HIV-1 infection are important determinants of regimen selection.
Open-label study in 753 subjects randomized equally to efavirenz or ...lopinavir/ritonavir(r) plus two nucleoside reverse-transcriptase inhibitor (NRTI) vs. the NRTI-sparing regimen of lopinavir/r plus efavirenz. Zidovudine, stavudine, or tenofovir with lamivudine was selected prior to randomization. Metabolic outcomes through 96 weeks were lipoatrophy, defined as at least 20% loss in extremity fat, and fasting serum lipids.
Lipoatrophy by dual-energy X-ray absorptiometry at week 96 occurred in 32% 95% confidence interval (CI) 25-39% of subjects in the efavirenz plus two NRTIs arm, 17% (95% CI 12-24) in the lopinavir/r plus two NRTIs arm, and 9% (95% CI 5-14) in the NRTI-sparing arm (P < or = 0.023 for all comparisons). Varying the definition of lipoatrophy (> or =10 to > or =40% fat loss) and correction for baseline risk factors did not affect the significant difference in lipoatrophy between the NRTI-containing regimens. Lipoatrophy was most frequent with stavudine-containing regimens and least frequent with tenofovir-containing regimens (P < 0.001), which were not significantly different from the NRTI-sparing regimen. Total cholesterol increases at week 96 were greatest in the NRTI-sparing arm (median +57 mg/dl) compared with the other two arms (+32-33 mg/dl; P < 0.001). Use of lipid-lowering agents was more common (25 vs. 11-13%) in the NRTI-sparing arm.
Lipoatrophy was more frequent with efavirenz than lopinavir/r when combined with stavudine or zidovudine, and less frequent when either drug was combined with tenofovir. Lipoatrophy was least frequent with the NRTI-sparing regimen, but this benefit was offset by greater cholesterol elevations and the need for lipid-lowering agents.
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