No abstract

Meteorites, Fe and Si-rich microspherules, positive Ir and Pt anomalies, and burned charcoal-rich Hopewell habitation surfaces demonstrate that a cosmic airburst event occurred over the Ohio River valley during the late Holocene. A comet-shaped earthwork was constructed near the airburst epicenter. Twenty-nine radiocarbon ages establish that the event occurred between 252 and 383 CE, a time when 69 near-Earth comets were documented. While Hopewell people survived the catastrophic event, it likely contributed to their cultural decline. The Hopewell airburst event expands our understanding of the frequency and impact of cataclysmic cosmic events on complex human societies.

No abstract

AimIndividuals experience differential risks in their initiation into drug injecting based on their gender. Data suggest women are more likely to be injected after their initiator and to share injection equipment. Little is known, however, regarding how gender influences the risk that people who inject drugs (PWID) may assist others into injection initiation. We therefore sought to investigate the role of “initiator” gender in the provision of injection initiation assistance across multiple settings.MethodsWe employed data from PReventing Injecting by Modifying Existing Responses (PRIMER), a multi-cohort study investigating factors influencing injection initiation assistance provision. Data were drawn from three cohort studies of PWID in San Diego, USA (STAHR II); Tijuana, Mexico (El Cuete IV); and Vancouver, Canada (VDUS). Site-specific logistic regression models were fit, with lifetime provision of injection initiation assistance as the outcome and gender as the independent variable.ResultsOverall, 3.2% (24/746) of the women and 4.6% (63/1367) of the men reported providing injection initiation assistance. In Tijuana, men were more than twice as likely to have provided injection initiation assistance after controlling for potential confounders (adjusted odds ratio = 2.17, 95% confidence interval: 1.22–3.84). Gender was not significantly associated with providing injection initiation assistance in other sites.ConclusionWe identified that being male in Tijuana, specifically, was associated with providing injection initiation assistance, which could inform targeted outreach aimed at reducing the influence of PWID populations on non-injectors in this site. This will likely require that existing interventions address gender- and site-specific factors for effectiveness.

No abstract

No abstract

In 2017, there were large increases (260-500%) in overdose deaths among women in the United States across age groups (30-64 years and 55-64 years). In addition, U.S. women who inject drugs (WWID) are at increased risk for substance use-related disease transmission, bacterial infections, as well as sexual and physical violence compared to men who inject drugs. Relatedly, women face unique access barriers to substance use-related services, such as stigma and low coverage of gender-specific drug use-related services. Despite these heightened risks experienced by WWID, interventions specifically tailored to preventing women from transitioning into injection drug use have not been developed to date. As such, we advocate for the development of gender-responsive programs to prevent injection drug use initiation. This is critical to ensuring a comprehensive approach to preventing injection drug use initiation among those populations at highest risk of injection-related morbidity and mortality.

The city of Tikal, a major center of the ancient Maya world, has been the focus of archaeological research for over a century, yet the interactions between the Maya and the surrounding Neotropical forests remain largely enigmatic. To help fill that void, our study used a powerful new technology, environmental DNA analysis, which enabled us to characterize the site core vegetation associated with the artificial reservoirs that served as the city water supply. Because the area has no permanent water sources, these reservoirs were key to the survival of the city. In the absence of specific evidence, the nature of the vegetation surrounding the reservoirs has been the subject of scientific hypotheses for decades. To address these hypotheses we proceeded to capture homologous sequences of vascular plant DNA extracted from reservoir sediments using 120-bp genetic probes in a targeted enrichment approach. Samples date from the Early Preclassic period (1780 − 1620 BCE) to the Early Postclassic period (900–1100 CE), encompassing the time before, during and after the occupation of Tikal (1000 BCE-900 CE). Results indicate that during the Maya occupation the banks of the ancient reservoirs were primarily fringed with native tropical forest vegetation rather than domesticated species.