Gibbons exploit information about what a competitor can see.

How much nonhuman animals understand about seeing has been the focus of comparative cognition research for decades. Many social primates (and other species) are sensitive to cues about what others can and cannot see. Whether this sensitivity evolved in primates through shared descent or convergent evolution remains unclear. The current study tested gibbons-the apes that are least studied yet most distantly related to humans and one of the less social primates-in two food-competition tasks. Specifically, we presented eastern hoolock gibbons, Hoolock leuconedys, and silvery gibbons, Hylobates moloch, with a choice between a contested piece of food visible to both themselves and a human competitor and an uncontested piece visible only to themselves. Subjects successfully stole the uncontested food when the competitor turned away his body (N = 10, experiment 1) and his head (N = 9, experiment 2). However, when the head of the experimenter was oriented towards the contested piece of food, whether the competitor opened or closed his eyes made no difference. Subjects' sensitivity to body- and head-orientation cues was comparable to that of chimpanzees, rhesus macaques, and ring-tailed lemurs-species living in much larger groups than gibbons. These findings support the continuity hypothesis that sensitivity to body- and head-orientation cues is a product of shared descent among primates.

Why intergroup variation matters for understanding behaviour.

Intergroup variation (IGV) refers to variation between different groups of the same species. While its existence in the behavioural realm has been expected and evidenced, the potential effects of IGV are rarely considered in studies that aim to shed light on the evolutionary origins of human socio-cognition, especially in our closest living relatives-the great apes. Here, by taking chimpanzees as a point of reference, we argue that (i) IGV could plausibly explain inconsistent research findings across numerous topics of inquiry (experimental/behavioural studies on chimpanzees), (ii) understanding the evolutionary origins of behaviour requires an accurate assessment of species' modes of behaving across different socio-ecological contexts, which necessitates a reliable estimation of variation across intraspecific groups, and (iii) IGV in the behavioural realm is increasingly likely to be expected owing to the progressive identification of non-human animal cultures. With these points, and by extrapolating from chimpanzees to generic guidelines, we aim to encourage researchers to explicitly consider IGV as an explanatory variable in future studies attempting to understand the socio-cognitive and evolutionary determinants of behaviour in group-living animals.

The High Efficiency of Anionic Dye Removal Using Ce-Al13/Pillared Clay from Darbandikhan Natural Clay.

Natural clay from Darbandikhan (DC) was evaluated in its natural form, after acid activation (ADC), and after pillaring (PILDC) as a potential adsorbent for the adsorption of methyl orange (MO) as a model anionic dye adsorbate. The effect of different clay treatments was investigated using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscope (SEM) and Fourier-Transform Infrared Spectroscopy (FT-IR), and N2 physisorption analysis. Both acid activation and pillaring resulted in a significant increase in adsorption affinity, respectively. The adsorption favored acidic pH for the anionic dye (MO). The adsorption process was found to follow pseudo-second-order kinetics with activation energies of 5.9 and 40.1 kJ·mol-1 for the adsorption of MO on ADC and PILDC, respectively, which are characteristic of physical adsorption. The adsorption isotherms (Langmuir, Redlich-Peterson and Freundlich) were fitted well to the experimental data. The specific surface area of the natural clay was very low (22.4 m2·g-1) compared to high-class adsorbent materials. This value was increased to 53.2 m2·g-1 by the pillaring process. Nevertheless, because of its local availability, the activated materials may be useful for the cleaning of local industrial wastewaters.

Chimpanzees (Pan troglodytes) strategically manipulate their environment to deny conspecifics access to food.

Humans modify their environment to grant or prevent others' access to valuable resources, for example by using locks. We tested whether sanctuary-living chimpanzees (N = 10) would flexibly modify their environment to either allow or deny a dominant conspecific access to a shared food source by giving them the option to change a food reward's pathway prior to releasing it. The food could end up in one of two locations: one was accessible to both the subject and a dominant conspecific, the other one was only accessible to the subject. We further manipulated the extent of inhibitory control needed for modifying the pathway by varying the subjects' starting position. Our subjects reoriented the pathway competitively to monopolize food but changed the pathway less often in trials with high inhibitory demands. We further show how inhibitory task demands in a social context influence chimpanzees' future planning. Our results show that chimpanzees will strategically manipulate their environment to maximize their own and deny a dominant conspecific access to food.

How environmental unpredictability and harshness affect chimpanzees (Pan troglodytes) in risk-choice and temporal discounting tasks.

Animals need to adjust their decision-making strategies to the ecological challenges of their environment. Variation in ecological unpredictability and harshness thus seem to affect their decisions in the wild. In our study, we combine methods from human life history theory and previous comparative work with chimpanzees to investigate whether current variability in ecological factors such as reward unpredictability and harshness affect chimpanzees' decision-making strategies in two value-based scenarios. We presented chimpanzees with choices varying in the probability of obtaining food rewards (risk-choice task) and in their temporal availability (temporal discounting task). These scenarios were preceded by different sets of priming phases mimicking variability in resource unpredictability (predictable or unpredictable rewards) and harshness (abundant or scarce rewards). In addition, we implemented a social manipulation to explore whether variations in unpredictable gains and losses affected chimpanzees' performance in both tasks. We found that chimpanzees were only affected by the social manipulation in the risk-choice scenario. Specifically, after a period of constant food losses chimpanzees became less risk prone. We discuss how different types of negative experiences affect chimpanzees' decisions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Natural incorporation of mercury in bone.

Mercury (Hg) is a highly toxic element that causes bone defects and malformations. Structure and surface analyses using quantitative x-ray diffraction using the Rietveld method, High-Resolution Transmission Electron Microscopy and nanodiffraction analyses, and Fourier-Transformed Infrared spectroscopy showed that bone enriched naturally with Hg (≤ 2.3 %) contained Hg3PO4 [(Hg2)3(PO4)2] and HgO. Bone [mostly as apatite, verified as carboxyapatite Ca10(PO4)4(CO3)3(OH)2(s)] and cinnabar (HgS) dissolved releasing Hg+ (existing as dimer Hg22+) and PO43-, both of which became immobilized as (Hg2)3(PO4)2. Besides, released Hg2+ became oxidized to form HgO. The outcome of this work is novel, provided that only a handful of stable compounds of Hg22+ are found in nature.

A novel nZVI-bentonite nanocomposite to remove trichloroethene (TCE) from solution.

Nanoscale zero-valent iron (nZVI) based (nano)composites supported by clay mineral substrates are a promising technology for the in-situ remediation of groundwater and (sub)soils contaminated with chlorinated hydrocarbons, such as trichloroethene (TCE). However, the physicochemical processes and interaction mechanisms between nZVI particles, clay minerals and TCE are poorly understood, yet. We immobilized nZVI particles on a commercial bentonite substrate to prepare a novel nZVI-B nanocomposite and tested its performance for TCE removal from solution against pure nZVI in batch reactors. The nZVI-B exhibited a higher reactivity (2.2·10-3 L h-1·m-2) and efficiency (94%) for TCE removal than nZVI (2.2·10-4 L h-1·m-2; 45%). Sorption of TCE onto the clay surfaces and reductive de-chlorination in "micro-reactors" developing within the nZVI-B controlled the kinetics and the magnitude of TCE loss from solution. Contrary to pure nZVI, no signs of nZVI particle agglomeration or inactivation due to oxide shell formation were found in nZVI-B. We attribute this to the uptake of dissolved Fe species that are liberated via progressing nZVI particle corrosion by the bentonite substrate to form Fe-smectite (nontronite domains), which prevented from a deterioration of the properties and reactivity of the nZVI-B. The use of nZVI-B in permeable reactive barriers at contaminated field sites could be feasible, where a system-inherent reduction of the soil-bearing capacity has to be minimized.

Chimpanzees behave prosocially in a group-specific manner.

Chimpanzees act cooperatively in the wild, but whether they afford benefits to others, and whether their tendency to act prosocially varies across communities, is unclear. Here, we show that chimpanzees from neighboring communities provide valuable resources to group members at personal cost, and that the magnitude of their prosocial behavior is group specific. Provided with a resource-donation experiment allowing free (partner) choice, we observed an increase in prosocial acts across the study period in most of the chimpanzees. When group members could profit (test condition), chimpanzees provided resources more frequently and for longer durations than when their acts produced inaccessible resources (control condition). Strikingly, chimpanzees' prosocial behavior was group specific, with more socially tolerant groups acting more prosocially. We conclude that chimpanzees may purposely behave prosocially toward group members, and that the notion of group-specific sociality in nonhuman animals should crucially inform discussions on the evolution of prosocial behavior.

Characterization of Tagaran natural clay and its efficiency for removal of cadmium (II) from Sulaymaniyah industrial zone sewage.

The fine fraction of the Tagaran natural clay (TC) from the Kurdistan region of Iraq-Sulaimani was characterized and used to remove Cd ions from industrial swage. Using XRF, XRD, SEM, and FTIR, the dominant clay mineral of the Tagaran clay mineral was identified as saponite, with minor amounts of chlorite. The clay was examined for its efficiency to adsorb and remove (Cd2+) in the presence of other heavy metal contaminants from Sulaimani industrial zone sewage by a batch method. The effect of initial pH, equilibrium time, temperature, clay dosage, and Cd2+ concentration was studied. Results were evaluated using Langmuir, Freundlich, Temkin, and Redlich-Peterson isotherms. The kinetics could be best fitted to pseudo-second-order reaction kinetic model. In addition, the activation energy and the amount of calculated and experimentally determined heavy metal loads were consistent. The thermodynamic studies showed spontaneous endothermic adsorption. The trioctahedral smectite (saponite) showed a good efficiency for the adsorption of Cd2+ from the real sample (up to 100%) which at least partly can be explained by cation exchange. Tagaran clay is a candidate material for the production of an adsorber material for removing Cd2+ from aqueous solutions.

Investigation of hydrated smectite microstructure through wet environmental transmission electron microscopy.

Water is an essential constituent of all biological materials as well as many non-biological materials. Not only the removal of water may result in undesirable morphological and structure change, the inability to sustain the hydrated conditions in the microscope also prevents the study of reactions which take place in aqueous environment. In order to overcome these problems we used wet environmental-cell transmission electron microscopy TEM (WETEM). Conventional TEM of dry smectite showed well-defined particle outlines (but without a specific shape) and typical smectite aggregates. Selected area electron diffraction (SAD) of dry particles showed stacking of smectite particles (i.e., aggregate) in very clear dot and ring patterns. In contrast, WETEM depicted well-dispersed clay particles showing a variety of different particle shapes. Analysis of SAD patterns obtained from dry and hydrated states illustrated a lattice change in different environments. The small lattice expansion in (h k 0) resulted from the expansion of the (0 0 l) plane resulting from the addition of water molecules in the crystal along the c-axis.

Antibacterial clay against gram-negative antibiotic resistant bacteria.

Antibiotic resistant bacteria persist throughout the world because they have evolved the ability to express various defense mechanisms to cope with antibiotics and the immune system; thus, low-cost strategies for the treatment of these bacteria are needed, such as the usage of environmental minerals. This paper reports the antimicrobial properties of a clay collected from Brunnenberg, Germany, that is composed of ferroan saponite with admixtures of quartz, feldspar and calcite as well as exposed or hidden (layered at inner regions) nano Fe(0). Based on the growth curves (log phase) of six antibiotic resistant bacteria (4 gram-negative and 2 gram-positive), we concluded that the clay acted as a bacteriostat; however, the clay was only active against the gram-negative bacteria (except for resilient Klebsiella pneumonia). The bacteriostatic mode of action was evidenced by the initial lack of Colony Forming Units on agar plates with growth registered afterward, certainly after 24h, and can be explained because interactions between membrane lipopolysaccharides and the siloxane surfaces of the clay. Labile or bioavailable Fe in the clay (extracted by EDTA or DFO-B) induced the quantitative production of HO as well as oxidative stress, which, nevertheless, did not account for by its bacteriostatic activity.

Analysis of Wellbore Skin Samples-Typology, Composition, and Hydraulic Properties.

The presence of a wellbore skin layer, formed during the drilling process, is a major impediment for the energy-efficient use of water wells. Many models exist that predict its potential impacts on well hydraulics, but so far its relevant hydraulic parameters were only estimates or, at best, model results. Here, we present data on the typology, thickness, composition, and hydraulic properties obtained from the sampling of excavated dewatering wells in lignite surface mines and from inclined core drilling into the annulus of an abandoned water well. Despite the limited number of samples, several types of skin were identified. Both surface cake filtration and particle straining in the aquifer occur. The presence of microcracks may be a determining feature for the hydraulic conductivity of skin layers. In the case of the well-developed water supply well, no skin layer was detected. The observed types and properties of wellbore skin samples can be used to test the many mathematical skin models.

Role of bentonite clays on cell growth.

Bentonites, naturally occurring clays, are produced industrially because of their adsorbent capacity but little is known about their effects on human health. This manuscript reports on the effect of bentonites on cell growth behaviour. Bentonites collected from India (Bent-India), Hungary (Bent-Hungary), Argentina (Bent-Argentina), and Indonesia (Bent-Indonesia) were studied. All four bentonites were screened in-vitro against two human cancer cell lines [U251 (central nervous system, glioblastoma) and SKLU-1 (lung adenocarcinoma)] supplied by the National Cancer Institute (USA). Bentonites induced growth inhibition in the presence of U251 cells, and growth increment in the presence of SKLU-1 cells, showing that interactions between bentonite and cell surfaces were highly specific. The proliferation response for U251 cells was explained because clay surfaces controlled the levels of metabolic growth components, thereby inhibiting the development of high-grade gliomas, particularly primary glioblastomas. On the other hand, the proliferation response for SKLU-1 was explained by an exacerbated growth favoured by swelling, and concomitant accumulation of solutes, and their hydration and transformation via clay-surface mediated reactions.

Corrosion of high-level radioactive waste iron-canisters in contact with bentonite.

Several countries favor the encapsulation of high-level radioactive waste (HLRW) in iron or steel canisters surrounded by highly compacted bentonite. In the present study the corrosion of iron in contact with different bentonites was investigated. The corrosion product was a 1:1 Fe layer silicate already described in literature (sometimes referred to as berthierine). Seven exposition test series (60 °C, 5 months) showed slightly less corrosion for the Na-bentonites compared to the Ca-bentonites. Two independent exposition tests with iron pellets and 38 different bentonites clearly proved the role of the layer charge density of the swelling clay minerals (smectites). Bentonites with high charged smectites are less corrosive than bentonites dominated by low charged ones. The type of counterion is additionally important because it determines the density of the gel and hence the solid/liquid ratio at the contact to the canister. The present study proves that the integrity of the multibarrier-system is seriously affected by the choice of the bentonite buffer encasing the metal canisters in most of the concepts. In some tests the formation of a patina was observed consisting of Fe-silicate. Up to now it is not clear why and how the patina formed. It, however, may be relevant as a corrosion inhibitor.

Calcium-ammonium exchange experiments on clay minerals using a (45)Ca tracer technique in marine pore water.

Understanding cation exchange processes is important for evaluating early diagenetic and synsedimentary processes taking place in marine sediments. To quantify calcium (Ca) exchange and Ca-ammonium exchange in a seawater environment, we performed experiments with a radioactive (45)Ca tracer on clay mineral standards (Fithian illite, montmorillonite and kaolinite) and marine sediments from the North Atlantic Integrated Ocean Drilling Program Site U1306A in artificial seawater (ASW). The results show that equilibrium during the initial attachment of Ca as well as the exchange of Ca by [Formula: see text] is attained in less than 2 min. On average 8-20% of the exchangeable sites of the clay minerals were occupied by Ca in a seawater medium. The conditional selectivity coefficient, describing the [Formula: see text] exchange in ASW is mineral specific and it was determined to be 0.07 for montmorillonite, 0.05 for a natural marine sediment and 0.013 for Fithian illite.

Porosity and distribution of water in perlite from the island of Milos, Greece.

A perlite sample representative of an operating mine in Milos was investigated with respect to the type and spatial distribution of water. A set of different methods was used which finally provided a consistent view on the water at least in this perlite. Infrared spectroscopy showed the presence of different water species (molecular water and hydroxyl groups / strongly bound water). The presence of more than 0.5 mass% smectite, however, could be excluded considering the cation exchange capacity results. The dehydration measured by thermal analysis occurred over a wide range of temperatures hence confirming the infrared spectroscopical results. Both methods point to the existence of a continuous spectrum of water binding energies. The spatial distribution of water and/or pores was investigated using different methods (CT: computer tomography, FIB: scanning electron microscopy including focused ion beam technology, IRM: infrared microscopy). Computer tomography (CT) showed large macropores (20 - 100 µm) and additionally revealed a mottled microstructure of the silicate matrix with low density areas up to a few µm in diameter. Scanning electron microscopy (FIB) confirmed the presence of µm sized pores and IRM showed the filling of these pores with water. In summary, two types of pores were found. Airfilled 20 - 100 µm pores and µm-sized pores disseminated in the glass matrix containing at least some water. Porosity measurements indicate a total porosity of 26 Vol%, 11 Vol% corresponding to the µm-sized pores. It remains unsolved wether the water in the µm-sized pores entered after or throughout perlite formation. However, the pores are sealed and no indications of cracks were found which indicated a primary source of the water, i.e. water was probably entrapped by quenching of the lava. The water in these pores may be the main reason for the thermal expandability which results in the extraordinarily porous expanded perlite building materials.

Lipid peroxidation and cytotoxicity induced by respirable volcanic ash.

This paper reports that the main component of respirable volcanic ash, allophane, induces lipid peroxidation (LP), the oxidative degradation of lipids in cell membranes, and cytotoxicity in murin monocyle/macrophage cells. Naturally-occurring allophane collected from New Zealand, Japan, and Ecuador was studied. The quantification of LP was conducted using the Thiobarbituric Acid Reactive Substances (TBARS) assay. The cytotoxic effect was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide colorimetric assay. Electron-Paramagnetic Resonance (EPR) determinations of naturally-occurring allophane confirmed the incorporation in the structure and clustering of structural Fe(3+), and nucleation and growth of small-sized Fe (oxyhydr)oxide or gibbsite. LP induced by allophane varied with time, and solid concentration and composition, reaching 6.7 ± 0.2 nmol TBARS mg prot(-1). LP was surface controlled but not restricted by structural or surface-bound Fe(3+), because redox processes induced by soluble components other than perferryl iron. The reactivity of Fe(3+) soluble species stemming from surface-bound Fe(3+) or small-sized Fe(3+) refractory minerals in allophane surpassed that of structural Fe(3+) located in tetrahedral or octahedral sites of phyllosilicates or bulk iron oxides. Desferrioxamine B mesylate salt (DFOB) or ethylenediaminetetraacetic acid (EDTA) inhibited LP. EDTA acted as a more effective inhibitor, explained by multiple electron transfer pathways. Registered cell-viability values were as low as 68.5 ± 6.7%.

Identification of iron-cyanide complexes in contaminated soils and wastes by Fourier transform infrared spectroscopy.

Persistent cyanide species in soil are mainly iron-cyanide (Fe-CN) complexes. They originate from anthropogenic inputs of compounds such as Fe4[Fe(II)(CN)6]3 in deposited gas-purifier wastes (GPW) or K2Zn3[Fe(II)(CN)6]2 in deposited blast-furnace sludge (BFSI). Fe-CN species in de-inking sludge (DIS) and sewage farm soils (SF) are still unknown. We investigated 35 soil and waste samples from 15 European sites and five synthesized Fe-CN-containing compounds by Fourier transform infrared spectroscopy. Furthermore, we determined the contents of total and adsorbed CN and pH. In all samples (pH 2.2-9.5), adsorbed Fe-CN complexes were negligible. In GPW and DIS samples, Fe4[Fe(II)(CN)6]3 and KFe[FeII(CN)6] were the only Fe-CN compounds (total CN contents 0.4-449 g kg(-1)). Several BFSI samples were free of CN. The spectra of other BFSI samples partially indicated dissolution of the characteristic compound K2Zn3[Fe(II)(CN)6]2, resulting in a loss of CN (contents < 12.3 g kg(-1)). Distinctive changes in BFSI with respect to CN speciation occurred within relatively short periods, <20 years. Dissolution of K2Zn3[Fe(II)(CN)6]2 was followed by dissociation of free CN from [Fe(CN)6](3-/4-) and adsorption of [Fe(II)(CN)6](4-) on organic surfaces. In DIS and SF samples, Fe4[Fe(11)(CN)6]3 and K2Zn3[Fe(II)(CN)6]2 (SF only) were identified.