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Mitigating ammonia (NH 3 ) emissions is a significant challenge, given its well-recognized role in the troposphere, contributing to secondary particle formation and impacting acid rain. The difficulty arises from the highly uncertain attribution of atmospheric NH 3 to specific emission sources, especially when accounting for diverse environments and varying spatial and temporal scales. In this study, we established a refined δ 15 N fingerprint for eight emission sources, including three previously overlooked sources of potential importance. We applied this approach in a year-long case study conducted in urban and rural sites located only 40 km apart in the Shandong Peninsula, North China Plain. Our findings highlight that although atmospheric NH 3 concentrations and seasonal trends exhibited similarities, their isotopic compositions revealed significant distinctions in the primary NH 3 sources. In rural areas, although agriculture emerged as the dominant emission source (64.2 ± 19.5%), a previously underestimated household stove source also played a considerably greater role, particularly during cold seasons (36.5 ± 12.5%). In urban areas, industry and traffic (33.5 ± 15.6%) and, surprisingly, sewage treatment (27.7 ± 11.3%) associated with high population density were identified as the major contributors. Given the relatively short lifetime of atmospheric NH 3 , our findings highlight the significance of the isotope approach in offering a more comprehensive understanding of localized and seasonal influences of NH 3 sources compared to emissions inventories. The refined isotopic fingerprint proves to be an effective tool in distinguishing source contributions across spatial and seasonal scales, thereby providing valuable insights for the development of emission mitigation policies aimed at addressing the increasing NH 3 burden on the local atmosphere.

Background: Knowledge on the epidemiological features and transmission patterns of novel coronavirus disease (COVID-19) is accumulating. Detailed line-list data with household settings can advance the understanding of COVID-19 transmission dynamics., Methods: A unique database with detailed demographic characteristics, travel history, social relationships, and epidemiological timelines for 1407 transmission pairs that formed 643 transmission clusters in mainland China was reconstructed from 9120 COVID-19 confirmed cases reported during 15 January-29 February 2020. Statistical model fittings were used to identify the superspreading events and estimate serial interval distributions. Age- and sex-stratified hazards of infection were estimated for household vs nonhousehold transmissions., Results: There were 34 primary cases identified as superspreaders, with 5 superspreading events occurred within households. Mean and standard deviation of serial intervals were estimated as 5.0 (95% credible interval [CrI], 4.4-5.5) days and 5.2 (95% CrI, 4.9-5.7) days for household transmissions and 5.2 (95% CrI, 4.6-5.8) and 5.3 (95% CrI, 4.9-5.7) days for nonhousehold transmissions, respectively. The hazard of being infected outside of households is higher for people aged 18-64 years, whereas hazard of being infected within households is higher for young and old people., Conclusions: Nonnegligible frequency of superspreading events, short serial intervals, and a higher risk of being infected outside of households for male people of working age indicate a significant barrier to the identification and management of COVID-19 cases, which requires enhanced nonpharmaceutical interventions to mitigate this pandemic., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Food can be health-giving. A global transition towards plant-based diets may equally help curb carbon emissions, slow land-system change and conserve finite resources. Yet, projected benefits of such 'planetary health' diets imperfectly capture the environmental or societal health outcomes tied to food production. Here, we examine pesticide-related hazards of fruit and vegetable consumption, and list proven management alternatives per commodity, geography and chemical compound. Across countries, pesticide use in these alleged healthful foods is extensive with up to 97% food items containing residues and up to 42% posing dietary risks to consumers. Multiple residues are present in 70-92% of US- and China-grown stone fruit while 58% US cauliflower is tainted with neonicotinoid insecticides. Science-based alternatives and decision-support frameworks can help food producers reduce risks and potential harm by deliberately abstaining from pesticide use. As such, opportunities abound to advance 'win-win' diets that simultaneously nurture human health and conserve global biodiversity., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The recent identification of cave paintings dated to 42-40 ka BP in Borneo and Sulawesi highlights the antiquity of painted representations in this region. However, no instances of three-dimensional portable art, well attested in Europe since at least 40 ka BP, were documented thus far in East Asia prior to the Neolithic. Here, we report the discovery of an exceptionally well-preserved miniature carving of a standing bird from the site of Lingjing, Henan, China. Microscopic and microtomographic analyses of the figurine and the study of bone fragments from the same context reveal the object was made of bone blackened by heating and carefully carved with four techniques that left diagnostic traces on the entire surface of the object. Critical analysis of the site's research history and stratigraphy, the cultural remains associated with the figurine and those recovered from the other archeological layers, as well as twenty-eight radiometric ages obtained on associated archeological items, including one provided by a bone fragment worked with the same technique recorded on the object, suggest a Late Paleolithic origin for the carving, with a probable age estimated to 13,500 years old. The carving, which predates previously known comparable instances from this region by 8,500 years, demonstrates that three-dimensional avian representations were part of East Asian Late Pleistocene cultural repertoires and identifies technological and stylistic peculiarities distinguishing this newly discovered art tradition from previous and contemporary examples found in Western Europe and Siberia., Competing Interests: The authors have declared that no competing interests exist.

Poxviruses are nucleocytoplasmic large DNA viruses encompassing two subfamilies, the Chordopoxvirinae and the Entomopoxvirinae, infecting vertebrates and insects, respectively. While chordopoxvirus genomics have been widely studied, only two entomopoxvirus (EPV) genomes have been entirely sequenced. We report the genome sequences of four EPVs of the Betaentomopoxvirus genus infecting the Lepidoptera: Adoxophyes honmai EPV (AHEV), Choristoneura biennis EPV (CBEV), Choristoneura rosaceana EPV (CREV), and Mythimna separata EPV (MySEV). The genomes are 80% AT rich, are 228 to 307 kbp long, and contain 247 to 334 open reading frames (ORFs). Most genes are homologous to those of Amsacta moorei entomopoxvirus and encode several protein families repeated in tandem in terminal regions. Some genomes also encode proteins of unknown functions with similarity to those of other insect viruses. Comparative genomic analyses highlight a high colinearity among the lepidopteran EPV genomes and little gene order conservation with other poxvirus genomes. As with previously sequenced EPVs, the genomes include a relatively conserved central region flanked by inverted terminal repeats. Protein clustering identified 104 core EPV genes. Among betaentomopoxviruses, 148 core genes were found in relatively high synteny, pointing to low genomic diversity. Whole-genome and spheroidin gene phylogenetic analyses showed that the lepidopteran EPVs group closely in a monophyletic lineage, corroborating their affiliation with the Betaentomopoxvirus genus as well as a clear division of the EPVs according to the orders of insect hosts (Lepidoptera, Coleoptera, and Orthoptera). This suggests an ancient coevolution of EPVs with their insect hosts and the need to revise the current EPV taxonomy to separate orthopteran EPVs from the lepidopteran-specific betaentomopoxviruses so as to form a new genus.