281 research outputs found
Testing the human factor: Radiocarbon dating the first peoples of the South Pacific
Archaeologists have long debated the origins and mode of dispersal of the immediate predecessors of all Polynesians and many populations in Island Melanesia. Such debates are inextricably linked to a chronological framework provided, in part, by radiocarbon dates. Human remains have the greatest potential for providing answers to many questions pertinent to these debates. Unfortunately, bone is one of the most complicated materials to date reliably because of bone degradation, sample pretreatment and diet. This is of particular concern in the Pacific where humidity contributes to the rapid decay of bone protein, and a combination of marine, reef, C₄, C₃ and freshwater foods complicate the interpretation of ¹⁴C determinations. Independent advances in bone pretreatment, isotope multivariate modelling and radiocarbon calibration techniques provide us, for the first time, with the tools to obtain reliable calibrated ages for Pacific burials. Here we present research that combines these techniques, enabling us to re-evaluate the age of burials from key archaeological sites in the Pacific
Liquefaction of Soils in the 1989 Loma Prieta Earthquake
The Loma Prieta Earthquake of October 17, 1989 was the most costly single natural disaster in U.S. history, resulting in losses of 9 billion, and claiming 63 lives. These damages were concentrated mainly at a number of distinct sites comprising a relatively small fraction of the affected region, as local site conditions and related geotechnical factors exerted a major influence on damage patterns and loss of life in this catastrophic event. This paper discusses one of these geotechnical factors, the widespread occurrence of soil liquefaction during the earthquake, as well as the associated damages and the resulting lessons learned. Additional significant geotechnical factors which exerted a strong influence on damage patterns during this event, including site-dependent dynamic response and seismically-induced slope instability, are discussed in companion papers in these proceedings
Disrupted Maturation of the Microbiota and Metabolome among Extremely Preterm Infants with Postnatal Growth Failure
Growth failure during infancy is a major global problem that has adverse effects on long-term health and neurodevelopment. Preterm infants are disproportionately affected by growth failure and its effects. Herein we found that extremely preterm infants with postnatal growth failure have disrupted maturation of the intestinal microbiota, characterized by persistently low diversity, dominance of pathogenic bacteria within the Enterobacteriaceae family, and a paucity of strictly anaerobic taxa including Veillonella relative to infants with appropriate postnatal growth. Metabolomic profiling of infants with growth failure demonstrated elevated serum acylcarnitines, fatty acids, and other byproducts of lipolysis and fatty acid oxidation. Machine learning algorithms for normal maturation of the microbiota and metabolome among infants with appropriate growth revealed a pattern of delayed maturation of the microbiota and metabolome among infants with growth failure. Collectively, we identified novel microbial and metabolic features of growth failure in preterm infants and potentially modifiable targets for intervention
Il nome e il sangue secondo Quinto Smirneo. Riprese e trasformazioni di un motivo del duello eroico
The aim of this essay is to examine the rules of duelling in Greek epic poetry from Homer and Arctinus to Quintus Smyrnaeus, within the perspective of composition by theme, which make it possible to identify heroes' ancestry as a specific motif of the epic
duel
Antibodies to Leptospira among blood donors in higher-risk areas of Australia: Possible implications for transfusion safety
BACKGROUND:
Leptospirosis is one of the most common bacterial zoonoses worldwide, and clinical manifestations range from asymptomatic infection to acute febrile illness, multi-organ failure and death. Asymptomatic, acute bacteraemia in a blood donor provides a potential for transfusion-transmission, although only a single such case from India has been recorded. Human leptospirosis is uncommon in developed countries; however, the state of Queensland in Australia has one of the highest rates among developed countries, especially after increased rainfall. This study examined the prevalence of antibodies to Leptospira spp. in blood donors residing in higher-risk areas of Australia, to evaluate the appropriateness of current blood safety guidelines.
MATERIALS AND METHODS:
Plasma samples collected from blood donors residing in higher-risk areas of Australia during 2009 and 2011 were included in the study. All samples were tested for the presence of antibodies to 22 leptospiral serovars using the microscopic agglutination test.
RESULT:
No sample had antibody titres suggestive of a current or recent infection, however, seven samples (1.44%, 95% CI: 0.38-2.50%) had titres suggestive of a past infection.
DISCUSSION:
This study provides data that may support the appropriateness of current relevant donor selection policies in Australia. Given that the risk profile for leptospirosis is expanding and that the infection is likely to become more prevalent with climate change, this disease may become more of a concern for transfusion safety in the futur
Metabolomics guides rational development of a simplified cell culture medium for drug screening against <i>Trypanosoma brucei</i>
n vitro culture methods underpin many experimental approaches to biology and drug discovery. The modification of established cell culture methods to make them more biologically relevant or to optimize growth is traditionally a laborious task. Emerging metabolomic technology enables the rapid evaluation of intra- and extracellular metabolites and can be applied to the rational development of cell culture media. In this study, untargeted semiquantitative and targeted quantitative metabolomic analyses of fresh and spent media revealed the major nutritional requirements for the growth of bloodstream form <i>Trypanosoma brucei</i>. The standard culture medium (HMI11) contained unnecessarily high concentrations of 32 nutrients that were subsequently removed to make the concentrations more closely resemble those normally found in blood. Our new medium, Creek's minimal medium (CMM), supports in vitro growth equivalent to that in HMI11 and causes no significant perturbation of metabolite levels for 94% of the detected metabolome (<3-fold change; α = 0.05). Importantly, improved sensitivity was observed for drug activity studies in whole-cell phenotypic screenings and in the metabolomic mode of action assays. Four-hundred-fold 50% inhibitory concentration decreases were observed for pentamidine and methotrexate, suggesting inhibition of activity by nutrients present in HMI11. CMM is suitable for routine cell culture and offers important advantages for metabolomic studies and drug activity screening
Gut Dysbiosis in Cutaneous T-Cell Lymphoma Is Characterized by Shifts in Relative Abundances of Specific Bacterial Taxa and Decreased Diversity in More Advanced Disease
Background Cutaneous T-cell lymphoma (CTCL) patients often suffer from recurrent skin infections and profound immune dysregulation in advanced disease. The gut microbiome has been recognized to influence cancers and cutaneous conditions; however, it has not yet been studied in CTCL.ObjectivesTo investigate the gut microbiome in patients with CTCL and in healthy controls.MethodsA case-control study was conducted between January 2019 and November 2020 at Northwestern’s busy multidisciplinary CTCL clinic (Chicago, Illinois, USA) utilizing 16S ribosomal RNA gene amplicon sequencing and bioinformatics analyses to characterize the microbiota present in fecal samples of CTCL patients (n = 38) and age-matched healthy controls (n = 13) from the same geographical region.ResultsGut microbial α-diversity trended lower in patients with CTCL and was significantly lower in patients with advanced CTCL relative to controls (P = 0.015). No differences in β-diversity were identified. Specific taxa were significantly reduced in patient samples; significance was determined using adjusted P-values (q-values) that accounted for a false discovery rate threshold of 0.05. Significantly reduced taxa in patient samples included the phylum Actinobacteria (q = 0.0002), classes Coriobacteriia (q = 0.002) and Actinobacteria (q = 0.03), order Coriobacteriales (q = 0.003), and genus Anaerotruncus (q = 0.01). The families Eggerthellaceae (q = 0.0007) and Lactobacillaceae (q = 0.02) were significantly reduced in patients with high skin disease burden.ConclusionsGut dysbiosis can be seen in patients with CTCL compared to healthy controls and is pronounced in more advanced CTCL. The taxonomic shifts associated with CTCL are similar to those previously reported in atopic dermatitis and opposite those of psoriasis, suggesting microbial parallels to the immune profile and skin barrier differences between these conditions. These findings may suggest new microbial disease biomarkers and reveal a new angle for intervention
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