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Black hole spectroscopy of collapsing and merging neutron stars
Get PDFBlack hole spectroscopy is an important pillar when studying gravitational waves from black holes and enables tests of general relativity. Most of the gravitational-wave signals observed over the last decade originate from binary black hole systems. Binary neutron star or black hole-neutron star systems are rarer but of particular interest for the next-generation ground-based gravitational-wave detectors. These events offer the exciting possibility of studying matter effects on the ringdown of "dirty black holes". In this work, we ask the question: Does matter matter? Using numerical-relativity, we simulate a wide range of collapsing neutron stars producing matter environments, both in isolated scenarios and in binary mergers. Qualitatively, the resulting ringdown signals can be classified into "clean", "modified", and "distorted" cases, depending on the amount of matter that is present. We apply standard strategies for extracting quasinormal modes of clean signals, using both theory-agnostic and theory-specific assumptions. Even in the presence of matter, possible modifications of quasinormal modes seem to be dominated by ringdown modeling systematics. We find that incorporating multiple quasinormal modes allows one to drastically reduce mismatches and errors in estimating the final black hole mass at early times. If not treated carefully, deviations in the fundamental quasinormal mode might artificially be overestimated and falsely attributed to the presence of matter or violations of general relativity
Im Spannungsfeld zwischen Mensch und Maschine: Künstliche Intelligenz und Magnetresonanztomographie in der Hirnforschung
No full textPlanktic foraminifera response to the early Eocene Climatic Optimum in the southern high-latitude Indian Ocean (ODP Site 738)
No full textA multi-proxy micropaleontological and geochemical study from Ocean Drilling Program (ODP) Site 738, a southern high-latitude site in the Indian Ocean, is presented. Variations in relative abundance and test size of the planktic foraminiferal species of the symbiotic upper mixed layer genera, Morozovella and Acarinina, and asymbiotic lower mixed layer genus, Subbotina, are analyzed across the Early Eocene Climate Optimum (EECO), a period associated with elevated atmospheric pCO₂ levels. During the early Eocene, Morozovella first decreased in abundance and finally locally disappeared, whereas Acarinina remained relatively abundant. Results indicate that the first early Eocene decline in relative abundance of morozovellids at Site 738 was probably earlier than in the northwest Pacific and Atlantic Oceans and southeast Atlantic Ocean. The early disappearance may have been due to the high paleolatitude of Site 738 (>60°S), differences in the water column structure, and nutrient availability. Size-dependent carbon stable isotope values are recorded for three target species, Subbotina velascoensis, Acarinina soldadoensis and Morozovella subbotinae. They show a significant morphological shift for the symbiotic foraminifera with decreasing in maximum test size from just before the J Carbon Isotope Excursion (CIE) event, and a reduction in the δ13C-test size gradient of the symbiotic monospecific foraminifera following the J CIE event. These changes may be due to reduced symbiotic activity (‘bleaching events’) driven by extreme environmental stress at the base of the EECO. However, test size of Acarinina soldadoensis returns toward its maximum size following the M CIE event
Young children enforce self-created norms promiscuously
No full textThree-year-old children normatively protest the transgression of adult rules in a variety of contexts. Five-year-olds also normatively protest the transgression of rules they have themselves created collaboratively with peers. But do children of these ages protest rules that they have created for themselves as individuals? We prompted five-year-olds (Study 1: 128 participants, 69 females) and three-year-olds (Study 2: 64 participants, 32 females) to devise a way to play with a toy in the presence of some puppet peers, after which a new puppet engaged with the toy the ‘wrong’ way. Results showed that five-year-olds protested at similar rates regardless of whether they came up with a way to play collaboratively with others and then played together (collaborative condition), came up with a way to play individually but then played together (two trendsetter conditions), or came up with a way to play and played totally individually (solo condition). In Study 2, three-year-olds protested self-created rules as well, albeit at lower rates than five-year-olds. Finally, neither age group’s protest seemed to be influenced by instructions containing explicit cues of normativity or conventionality (e.g., creating a game with rules vs coming up with a way to play). As such, when children create norms themselves, their willingness to protest novice transgressors seems not to be impacted by the degree to which these norms were created through collaboration. Moreover, our results show that promiscuous normativity of self-created norms emerges earlier than previously thought, around the same time children become promiscuous normativists towards adult-created norms
Proteomic Profiling Reveals Mitochondrial Dysregulation in Rapidly Progressive Alzheimer’s: Role of DLDH in Amyloid Beta Aggregation
No full textAlzheimer’s disease (AD) is presented as multiple clinical variants depending upon the rate of progression and familial background; however, the exact molecular mechanisms associated with these subtypes and their treatments are yet to be understood. The current study is based on a global proteome analysis of brain samples from patients (n = 38) with rapidly progressive AD (rpAD—survival time < 3 years), sporadic AD (spAD—survival time of 8–10 years), and healthy controls. Proteome analysis revealed a differential regulation of 79 proteins and highlighted the dysregulation of mitochondrial machinery and glucose metabolism in rpAD. Dihydrolipoamide dehydrogenase (DLDH), a mitochondrial oxidoreductase, showed a significant reduction and delocalization in rpAD. In vitro analysis revealed a potential role of DLDH in the aggregation of amyloid beta. Rapid progression in AD may be influenced by the energy homeostasis and redox dysfunction linked with the DLDH
From bone chemistry to human demography: Uncovering copper age society at Valencina (c. 2900–2650 BC)
No full textUntil recently, the study of Iberian Copper Age society was severely hampered by the limited availability of anthropological and demographic data. This was largely caused by the fact that the main reference sites for this period offered limited collections of human bone. With the turn of the 21st century this situation has gradually changed. In this paper we present a multi-disciplinary approach to a well-dated and well-contextualised collection of 126 individuals, retrieved from the Valencina Copper Age megasite (Sevilla, Spain). A host of methods are applied, including standard bioarchaeology, amelogenin peptides, stable strontium isotopes, aDNA and total mercury. The results offer the first methodologically complex view of Iberian Early Copper Age society, including themes such as burial rites, sex and age demographics, pathologies, mobility, biological kinship, ancestry and lifestyles. This reveals a fluid and diverse society based of a high degree of mobility and far-reaching connectivity, with limited social hierarchization and a striking prevalence of female leaders. This evidence suggests that further highresolution multi-method approaches need to be taken in order to understand early complex societies world-wide, as observations based on the ethnographic record may not provide entirely valid epistemological frameworks
Laser-carbonized anodes for sodium-ion batteries : a sustainable fabrication route toward spatially resolved and practical energy storage
No full textLaser-induced carbonization of polymer films offers a rapid, scalable, and additive-free route to functional carbon materials. Here, a hierarchically structured hard carbon anode is developed by laser carbonizing 5-hydroxymethylfurfural (HMF)-based films under ambient conditions. Optimizing laser power yields a vertically graded architecture with a graphitic-like surface and a disordered, microporous core. The resulting binder- and additive-free anode exhibits high electronic conductivity, ion-accessible porosity, and mechanical stability. Despite high areal mass loading (>4 mg cm-2), the anode delivers high reversible capacity, excellent rate capability, and >85 % capacity retention over 300 cycles. Operando Raman spectroscopy reveals phase-specific sodium storage mechanisms: surface-confined interactions in graphitic regions and highly reversible pore-filling in disordered domains. These insights clarify the roles of local structure and porosity in charge storage. This work demonstrates laser carbonization as a powerful platform for producing performance-tuned carbon electrodes for practical sodium-ion battery applications. Graphical abstract Download: Download high-res image (632KB) Download: Download full-size imag
Differential sampling for genetic analyses of Treponema pallidum and for radiocarbon dating in archaeological bone
No full textObjective: Molecular recovery of T. pallidum DNA in dry bone poses methodological challenges. Here we evaluate recovery success from a molecularly confirmed co-infection with yaws (T. pallidum pertenue) and plague (Y. pestis). Materials: Pulverised bone from three pathological anatomical elements from individual AGU007 excavated from Aguon & uogon; street, Vilnius, Lithuania was used for DNA analysis. Three additional anatomical elements from individual AGU007 were used to obtain radiocarbon dates. Methods: High-throughput sequencing of bulk DNA content followed by computational analysis. DNA sequencing and genomic analysis following molecular enrichment for T. pallidum. Radiocarbon dating combined with computational molecular dating. Results: T. pallidum and Y. pestis DNA were identified in a cranial fragment from individual AGU007. Radiocarbon dates from this individual combined with another narrowed the temporal range to the latter part of the 15th century at the 2-sigma level. Conclusions: Detection of T. pallidum DNA in multiple skeletal elements from an individual confirmed to have an active yaws infection at time of death gave further insight into preferred sampling locations for molecular detection of treponemal infections. While the highest molecular recovery came from teeth, the parietal bone provided adequate recovery. Significance: This research indicates that sampling for molecular analysis of T. pallidum infections should include (if available) one tooth and one lesion indicative of active infection at the time of death. Accommodating radiocarbon date probability distributions and Bayesian inference has the potential to increase molecular dating precision. Limitations: T. pallidum DNA preservation is not predictable across the skeleton. Suggestions for Further Research: We encourage ethical and minimalist sampling strategies for further research
