144 research outputs found

    Mapping Memory, Space and Conflict

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    Our introduction to the volume sets the discussion about memory in archaeology into current contexts, establishes our reasons for producing this book and discusses a number of crucial aspects of memory, space, and identity. We provide a brief history of memory studies with a focus on contributions from archaeology and discuss a number of topics that play important roles in the papers. These include the relations between forgetting and remem- bering, and between space, place and memory. Along with our authors, we emphasize that memory is a matter of practices, not just of mindsets. A further element in our discussions is the interface between memory, duration, and history. All of these issues coalesce in an important background theme, the political nature of various modes of memor

    Diurnal oscillations in gut bacterial load and composition eclipse seasonal and lifetime dynamics in wild meerkats.

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    Circadian rhythms in gut microbiota composition are crucial for metabolic function, yet the extent to which they govern microbial dynamics compared to seasonal and lifetime processes remains unknown. Here, we investigate gut bacterial dynamics in wild meerkats (Suricata suricatta) over a 20-year period to compare diurnal, seasonal, and lifetime processes in concert, applying ratios of absolute abundance. We found that diurnal oscillations in bacterial load and composition eclipsed seasonal and lifetime dynamics. Diurnal oscillations were characterised by a peak in Clostridium abundance at dawn, were associated with temperature-constrained foraging schedules, and did not decay with age. Some genera exhibited seasonal fluctuations, whilst others developed with age, although we found little support for microbial senescence in very old meerkats. Strong microbial circadian rhythms in this species may reflect the extreme daily temperature fluctuations typical of arid-zone climates. Our findings demonstrate that accounting for circadian rhythms is essential for future gut microbiome research

    Diurnal oscillations in gut bacterial load and composition eclipse seasonal and lifetime dynamics in wild meerkats

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    Circadian rhythms in gut microbiota composition are crucial for metabolic function, yet the extent to which they govern microbial dynamics compared to seasonal and lifetime processes remains unknown. Here, we investigate gut bacterial dynamics in wild meerkats (Suricata suricatta) over a 20-year period to compare diurnal, seasonal, and lifetime processes in concert, applying ratios of absolute abundance. We found that diurnal oscillations in bacterial load and composition eclipsed seasonal and lifetime dynamics. Diurnal oscillations were characterised by a peak in Clostridium abundance at dawn, were associated with temperature-constrained foraging schedules, and did not decay with age. Some genera exhibited seasonal fluctuations, whilst others developed with age, although we found little support for microbial senescence in very old meerkats. Strong microbial circadian rhythms in this species may reflect the extreme daily temperature fluctuations typical of arid-zone climates. Our findings demonstrate that accounting for circadian rhythms is essential for future gut microbiome research

    The hepatitis B virus PRE contains a splicing regulatory element

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    The posttranscriptional regulatory element (PRE) is considered to enhance hepatitis B virus (HBV) gene expression by facilitating the nuclear export of intronless viral subgenomic RNAs. Its role in the RNA metabolism of the viral pregenomic RNA (pgRNA) is currently unknown. We identified a positively cis-acting splicing regulatory element (SRE-1) and present two lines of evidence for its functionality. Firstly, in a heterologous context SRE-1 functionally substitutes for a retroviral bidirectional exonic splicing enhancer (ESE). As expected, SRE-1 is a splicing enhancer also in its natural viral sequence context, since deletion of SRE-1 reduces splicing of pgRNA in cell culture experiments. Secondly, we show that stimulation of HBV RNA splicing by the splicing factor PSF was repressed by the PRE. Analysis of a variety of PSF mutants indicated that RNA-binding and protein–protein interaction were required to enhance splicing. In addition, we show that the PRE contributed to pgRNA stability, but has little influence on its nuclear export. Herein, we report for the first time that the PRE harbors splicing stimulating and inhibiting regulatory elements controlling processing of the viral pregenome. We discuss a model in which the regulation of pgRNA splicing depends on cellular factors interacting with the PRE

    Chronic kidney disease induces a systemic microangiopathy, tissue hypoxia and dysfunctional angiogenesis

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    Chronic kidney disease (CKD) is associated with excessive mortality from cardiovascular disease (CVD). Endothelial dysfunction, an early manifestation of CVD, is consistently observed in CKD patients and might be linked to structural defects of the microcirculation including microvascular rarefaction. However, patterns of microvascular rarefaction in CKD and their relation to functional deficits in perfusion and oxygen delivery are currently unknown. In this in-vivo microscopy study of the cremaster muscle microcirculation in BALB/c mice with moderate to severe uremia, we show in two experimental models (adenine feeding or subtotal nephrectomy), that serum urea levels associate incrementally with a distinct microangiopathy. Structural changes were characterized by a heterogeneous pattern of focal microvascular rarefaction with loss of coherent microvascular networks resulting in large avascular areas. Corresponding microvascular dysfunction was evident by significantly diminished blood flow velocity, vascular tone, and oxygen uptake. Microvascular rarefaction in the cremaster muscle paralleled rarefaction in the myocardium, which was accompanied by a decrease in transcription levels not only of the transcriptional regulator HIF-1 alpha, but also of its target genes Angpt-2, TIE-1 and TIE-2, Flkt-1 and MMP-9, indicating an impaired hypoxia-driven angiogenesis. Thus, experimental uremia in mice associates with systemic microvascular disease with rarefaction, tissue hypoxia and dysfunctional angiogenesis

    Microbes, macrofauna, and methane: a novel seep community fueled by aerobic methanotrophy

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    During the discovery and description of seven New Zealand methane seep sites, an infaunal assemblage dominated by ampharetid polychaetes was found in association with high seabed methane emission. This ampharetid-bed assemblage had a mean density of 57,000 ± 7800 macrofaunal individuals m−2 and a maximum wet biomass of 274 g m−2, both being among the greatest recorded from deep-sea methane seeps. We investigated these questions: Does the species assemblage present within these ampharetid beds form a distinct seep community on the New Zealand margin? and What type of chemoautotrophic microbes fuel this heterotrophic community? Unlike the other macro-infaunal assemblages, the ampharetid-bed assemblage composition was homogeneous, independent of location. Based on a mixing model of species-specific mass and isotopic composition, combined with published respiration measurements, we estimated that this community consumes 29–90 mmol C m−2 d−1 of methane-fueled biomass; this is > 290 times the carbon fixed by anaerobic methane oxidizers in these ampharetid beds. A fatty acid biomarker approach supported the finding that this community, unlike those previously known, consumes primarily aerobic methanotrophic bacteria. Due to the novel microbial fueling and high methane flux rates, New Zealand's ampharetid beds provide a model system to study the influence of metazoan grazing on microbially mediated biogeochemical cycles, including those that involve greenhouse gas emission

    Gut microbiota individuality is contingent on temporal scale and age in wild meerkats

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    DATA ACCESSIBILITY : All sequences and processed data used in this study are available to download at Zenodo [54]. Sequences are additionally stored under NCBI BioProject PRJNA764180. R code can be downloaded at https://github.com/Riselya/Microbiome-repeatability.Inter-individual differences in gut microbiota composition are hypothesized to generate variation in host fitness—a premise for the evolution of host–gut microbe symbioses. However, recent evidence suggests that gut microbial communities are highly dynamic, challenging the notion that individuals harbour unique gut microbial phenotypes. Leveraging a long-term dataset of wild meerkats, we reconcile these concepts by demonstrating that the relative importance of identity for shaping gut microbiota phenotypes depends on the temporal scale. Across meerkat lifespan, year-to-year variation overshadowed the effects of identity and social group in predicting gut microbiota composition, with identity explaining on average less than 2% of variation. However, identity was the strongest predictor of microbial phenotypes over short sampling intervals (less than two months), predicting on average 20% of variation. The effect of identity was also dependent on meerkat age, with the gut microbiota becoming more individualized and stable as meerkats aged. Nevertheless, while the predictive power of identity was negligible after two months, gut microbiota composition remained weakly individualized compared to that of other meerkats for up to 1 year. These findings illuminate the degree to which individualized gut microbial signatures can be expected, with important implications for the time frames over which gut microbial phenotypes may mediate host physiology, behaviour and fitness in natural populations.German Research Foundation; European Research Council; Human Frontier Science; University of Zurich; MAVA Foundation.http://royalsocietypublishing.org/journal/rspbhj2023Mammal Research Institut

    Moral Reasoning in Psychopaths

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    Patienten mit der psychischen Störung „Psychopathie“ zeigen ein Muster von emotionaler Abgestumpftheit, Impulsivität und unmoralischem Verhalten. Zur Untersuchung moralischen Urteilens wurden in der vorliegenden Studie alltagsrelevante Konflikte mit moralischem bzw. neutralem Inhalt entwickelt und 12 „psychopathischen“ forensischen Patienten sowie 12 nicht-psychopathischen forensischen Patienten präsentiert. „Psychopathische“ im Vergleich zu nicht-psychopathischen Patienten berichteten signifikant positivere Gefühle bei unmoralischen Entscheidungen als Nicht-Psychopathen. Außerdem wurden in der Gruppe der „Psychopathen“ im Vergleich zu den Nicht-Psychopathen signifikant häufiger unmoralische Entscheidungen auf moralische Konflikte getroffen. Diese Befunde deuten darauf hin, dass eine Störung der Emotionsverarbeitung ursächlich für dissoziales Verhalten bei „Psychopathen“ sein könnte.Psychopathic patients show a behavioral pattern that is characterized by indifference, impulsivity and antisocial behavior. To investigate moral reasoning we developed conflicts of everyday life with either moral or neutral content. These conflicts were then presented to a group of 12 psychopathic forensic patients as well as to a group of 12 non-psychopathic forensic patients.Psychopathic compared to non-psychopathic patients reported significantly higher positive feelings when choosing an immoral response alternative than non-psychopaths. Furthermore, psychopaths picked significantly more often an immoral response alternative in the conflicts with moral content than did the non-psychopaths. These results indicate that impairment in emotional processing abilities may be at the core of antisocial behavior in psychopathy
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