Mineralogy, kaolin crystallinity, Fe content, δO18, and δD were determined for late Cretaceous “soft” and early Tertiary “hard” Georgia kaolins. The crystallinity of the <0.5-, 0.5–1.0-, and 1.0–2.0- μm size fractions of soft kaolins was higher than that of equivalent size fractions of hard kaolins. δO18 and δD of the soft and hard kaolins ranged between 18.5 to 23.1‰, and −64 to −41‰, respectively, and could not be used to discriminate soft from hard kaolins. The trends of crystallinity vs. δO18 were different for kaolins collected at different localities, and, for a given sample, δO18 generally decreased with increasing crystallinity and with increasing crystallite size. These data indicate that the Tertiary kaolins could not have been simply derived from the Cretaceous kaolins by winnowing unless post-sedimentation recrystallization of one or both occurred. δD vs. δO18 systematics indicate that the late Cretaceous to early Tertiary Georgia kaolins crystallized over a temperature range of about 15°C in the presence of waters that varied little in isotopic composition.

Reconstructing the origin of bentonitic clays is often a challenging and rather complicated undertaking, but the analysis of certain predictor clay minerals is proving to be an excellent method to simplify this process. The goal of the present investigation was to use abundance changes of five X-ray diffraction (XRD) predictor minerals to determine the relative contributions of weathering and parent-rock changes to the origin of clay minerals in Egyptian bentonitic clays as the test case. The XRD predictor minerals, selected in an earlier discriminant function analysis of quantitative abundances of 14 minerals, provided a simpler approach to the interpretation of clay-mineral origins because they are the minerals that were most responsible for statistically significant differences among the samples. Changes in mineral composition were basically a function of parent-rock lithology, drainage, and climate interactions. A Paleo-Climate Index (CI; the ratio of coarsely crystalline kaolinite to Fe-rich smectite), and a Parent-Rock Index (PI; the ratio of the illitic phases and quartz abundances to pure smectite) were established to track the paleo-climate and parent-rock changes, respectively. Low CI values indicated that a long, seasonally dry climate prevailed during the Middle Eocene, uppermost Eocene, Lower Miocene, and Upper Pliocene bentonitic clay deposition. Lowermost Upper Eocene and the Middle Miocene bentonitic clays were produced when a wet climate prevailed throughout the year. Moderate to high PI values suggested derivation of the clays from the acidic basement crystalline rocks at Uweinat-Bir Safsaf uplift and Lower Paleogene shales during the Middle Eocene and lowermost Upper Eocene. The youngest Upper Eocene and Lower Miocene materials contained abundant Fe-smectite and low PIs indicating derivation from tholeiitic basalts. Diagenetic and sedimentary segregation modifications were not apparent. Direct evidence for in situ derivation from volcanic precursor materials was lacking in general, but volcanic eruptions were common in the region. The minerals in the Egyptian bentonitic clays formed as weathering products on land and have been transported by north-flowing streams and rivers to the sites of accumulation.

Mineralogical and geochemical variations among the Carboniferous and Cretaceous sedimentary kaolin deposits from Sinai provided an opportunity to examine the effect of the source area on compositions of the deposits. The Carboniferous kaolin deposits are mineralogically and geochemically heterogeneous. The Khaboba and Hasbar deposits consist of kaolinite, quartz, anatase, illite, chlorite, zircon, and leucoxene. The shale-normalized rare earth element (REE) patterns of the Khaboba deposit showed a slight LREE over HREE enrichment ((La/Yb)SN = 1.19–1.51) with a MREE depletion (Gd/Gd*SN = 0.51–0.75), while the Hasbar kaolin had a MREE enrichment. The Abu Natash kaolin deposit consisted of kaolinite, anatase, and a little quartz with larger TiO2, Cr, and V and smaller Zr and Nb contents compared to other Carboniferous deposits. The shale-normalized REE patterns of the Abu Natash deposit exhibited a positive Eu anomaly (Eu/Eu*SN = 1.28–1.40) and a MREE enrichment (Gd/Gd*SN = 1.41–2.05). The Cretaceous deposits were relatively homogeneous in terms of mineralogical composition and geochemistry and are composed of kaolinite, quartz, anatase, rutile, zircon, and leucoxene. The Cretaceous kaolin deposits showed mostly flat shale-normalized REE patterns with a variable LREE depletion.

The presence of illite and chlorite, the absence of rutile, large Zr and Nb contents, and the REE patterns suggested a component of weathered low-grade metasediments as a source for the Carboniferous deposits in the Khaboba and Hasbar areas, while the large Ti, Cr, and V, and small quartz contents indicated mafic source rocks for the Abu Natash deposit. The abundance of high-Cr rutile and the absence of illite and chlorite, and large Zr, Ti, Cr, and V contents suggested a mixture of medium- to high-grade metamafic and granitic rocks as source rocks for the Cretaceous kaolin deposits. The occurrence of alkaline rocks in the source of the deposits studied was identified by high-Nb contents and the presence of bastnaesite. The mineralogical and geochemical heterogeneity and lesser maturity of the Carboniferous deposits suggested local sources for each deposit and their deposition in basins close to the sources. The mineralogical and geochemical homogeneity and maturity of the Cretaceous deposits, on the other hand, indicated common sources for all deposits and their deposition in relatively remote basins.

When we think about emotional ambiguity, we usually think about the feeling of ambivalence. However, in a recently proposed model, ambiguity might also be present in different emotional spaces, such as origin (dimensions of automaticity and reflectiveness) and activation (arousal and subjective significance) as proposed in the basics of dual-process theories. In two experiments, we checked for behavioural and psychophysical differences in processing words of origin and activation ambiguities while completing an emotionality rating task. In Experiment 1, we assessed emotionality ratings and reaction times; in Experiment 2, we used a webcam-based eye-tracking measurement to assess the number and mean duration of fixations. We found significant effects for words differing in origin and activation: the emotionality ratings increased within the intensity of origin ambiguity but decreased within the intensity of activation ambiguity; more and longer fixations were registered for words of higher origin ambiguity; and gradually fewer and shorter fixations were registered within increases in activation ambiguity. We found that the ambiguities on spaces of origin and activation produced their own main effects, but they also factored significantly into the interaction, modifying each other’s results. Our study is the first to show specifics of the perception of ambiguous stimuli on spaces other than valence.

Viruses are the most numerically abundant biological entities on Earth. As ubiquitous replicators of molecular information and agents of community change, viruses have potent effects on the life on Earth, and may play a critical role in human spaceflight, for life-detection missions to other planetary bodies and planetary protection. However, major knowledge gaps constrain our understanding of the Earth's virosphere: (1) the role viruses play in biogeochemical cycles, (2) the origin(s) of viruses and (3) the involvement of viruses in the evolution, distribution and persistence of life. As viruses are the only replicators that span all known types of nucleic acids, an expanded experimental and theoretical toolbox built for Earth's viruses will be pivotal for detecting and understanding life on Earth and beyond. Only by filling in these knowledge and technical gaps we will obtain an inclusive assessment of how to distinguish and detect life on other planetary surfaces. Meanwhile, space exploration requires life-support systems for the needs of humans, plants and their microbial inhabitants. Viral effects on microbes and plants are essential for Earth's biosphere and human health, but virus–host interactions in spaceflight are poorly understood. Viral relationships with their hosts respond to environmental changes in complex ways which are difficult to predict by extrapolating from Earth-based proxies. These relationships should be studied in space to fully understand how spaceflight will modulate viral impacts on human health and life-support systems, including microbiomes. In this review, we address key questions that must be examined to incorporate viruses into Earth system models, life-support systems and life detection. Tackling these questions will benefit our efforts to develop planetary protection protocols and further our understanding of viruses in astrobiology.

In this article I contrast two opposing forms of essentialism, definitional and transcendental versus productivist and historical, and trace both forms back to Kripke's Naming and Necessity (1980). Definitional essentialism, as developed by Fine, centers on kind-membership. Historical essentialism, as anticipated by Prior and developed by Almog, puts origin at its center. The article focuses on the fundamentally distinct manners in which these two views handle the necessity of origin thesis. In the final section of the article, inspired by a Nietzschean genealogical methodology, I pursue a naturalization strategy and conclude that rather than origin being necessary, it is essentialist necessity that reduces to origin.

On the western part of the eastern Indian shield, Archaean basement (Bonai granite) is overlain by radioactive conglomerate. The conglomerate contains well-rounded, fractured Mg-poor (<0.18 wt.% MgO), Al-rich (up to 21.14 wt.% Al2O3) Zn-rich chromite (>35.0 wt.% Cr2O3) containing up to 15.5 wt.% ZnO. This is the first reported occurrence of detrital zinc-rich chromite having such unusually high ZnO from India, and to our knowledge, the third reported occurrence in radioactive quartz-pebble conglomerate after Witwatersrand, South Africa and Tarkwa, Ghana. Zinc-rich chromite grains are either clean or contain exsolution blebs/lamella of rutile. The conglomerates show evidence for post-depositional hydrothermal fluid influx and fluid-induced mineral alteration. The strong negative correlation between Zn and Fe2+, Al and Cr, and Al and Fe3+, and strong positive correlation between Zn and Al suggest secondary incorporation of Zn and Al by substitution of Fe2+ and Cr (and Fe3+), respectively, leading to partial transformation of (Fe)(Cr,Al,Fe3+)2O4 towards ZnAl2O4 composition. The chromite grains were possibly derived from komatiite. The timing of Zn enrichment, either at the provenance prior to sedimentation, or at the depositional site post-dating sedimentation, remains unresolved.

This article analyzes the relationship between the relative position of an ethnic group, as measured by its majority/minority status at a subnational level, and attitudes of its members toward immigrants of different origins. Based on the Russian case, it addresses the question whether the effects of in-group majority status within a region on attitudes toward the general category of immigrants hold regardless of out-group origin and, if not, what may drive this variation. Using data from the Russia Longitudinal Monitoring Survey of the Higher School of Economics and Bayesian hierarchical structural equation modeling, the study demonstrates that the relative position of an ethnic in-group is of varying importance as a predictor of attitudes toward migrant groups of European versus non-European origin in Russia. A group’s majority status within a region proved to play a role in predicting attitudes toward migrants originating from the “south” (encompassing North and South Caucasus; Central Asia; and China, Vietnam, and Korea) but not toward migrants coming from the “west” (Ukraine and Moldova). We draw on arguments related to the source and the level of threat induced by the out-groups, ethnic hierarchies, and group cues to explain this pattern of results.

Geographical indications (GIs) are valuable attributes that enhance the competitiveness of agri-food products, generate added value and revitalize rural environments. The aim of this work was to analyze the attributes spring fruit consumers associate with GIs when they decide to purchase these products. Moreover, the changes in these associations with the increasing distance between the region of production and the place of consumption were also evaluated. We specifically analyzed two GIs used for spring fruits: the protected geographical indication for Mountain Cherries from Alicante (Spain) and the protected designation of origin for Loquats from Callosa d'En Sarriá (Spain). Data were analyzed using logistic regression analysis. The results show the significant association in consumers' minds between the preference for GI fruit and the importance attributed to the place of production (origin). The association of different attributes with the GI fruit label is product dependent as the number of attributes associated in the case of cherries (origin, organic, color and variety) is higher than for loquats (origin and variety). Regarding the distance between the production area and the place of consumption, our findings suggest that the closer the consumer is to the GI area of influence, the more attributes they associate with these labels. In this regard, increasing the knowledge of the GI labels beyond their area of influence could boost the demand for these products as consumers would be aware of the different quality attributes concentrated in that label.