One of the key reasons for the poor performance of natural enemies of honeydew-producing insect pests is mutualism between ants and some aphid species. The findings demonstrated that red wood ant, Formica rufa Linnaeus (Hymenoptera: Formicidae) had a deleterious impact on different biological parameters of the lady beetle, Hippodamia variegata Goeze (Coleoptera: Coccinellidae). H. variegata laid far fewer eggs in ant-tended aphid colonies, laying nearly 2.5 times more eggs in ant absence. Ants antennated and bit the lady beetle eggs, resulting in significantly low egg hatching of 66 per cent over 85 per cent in ant absent treatments. The presence of ants significantly reduced the development of all larval instars. The highest reduction was found in the fourth larval instar (31.33% reduction), and the lowest in the first larval instar (20% reduction). Later larval instars were more aggressively attacked by ants than earlier instars. The first and second larval instars stopped their feeding and movement in response to ant aggression. The third and fourth larval instars modified their mobility, resulting in increased ant aggression towards them. Adult lady beetles were shown to be more vulnerable to ant attacks than larvae. However, H. variegata adults demonstrated counterattacks in the form of diverse defensive reaction behaviours in response to F. rufa aggression.

A partir de los conceptos de modo y sistema cerámico, analizamos el rango de variación estilística en las cerámicas de El Tintal, Guatemala, como indicadores de conexiones sociales, económicas y políticas a nivel regional. Nuestro estudio muestra que la población de El Tintal participó en sistemas cerámicos con una distribución geográfica extensa durante los períodos preclásico medio y tardío, clásico temprano y clásico tardío. Durante los períodos preclásico terminal y clásico terminal, sin embargo, El Tintal participó en sistemas de afiliación con cobertura espacial limitada, aunque entre estos circulan conjuntos de cerámicas particulares a larga distancia. Con base en los resultados del estudio proponemos aquí algunas explicaciones a estos patrones en términos de dinámicas de interacción sociocultural y económicas.

Executive functions (EFs) in both regulatory and meta-cognitive contexts are important for a wide variety of children’s daily activities, including play and learning. Despite the growing literature supporting the relationship between EF and language, few studies have focused on these links during everyday behaviours. Data were collected on 208 children from 6 to 12 years old of whom 89 were deaf children (55% female; M = 8;8; SD = 1;9) and 119 were typically hearing children (56% female, M = 8;9; SD = 1;5). Parents completed two inventories: to assess EFs and language proficiency. Parents of deaf children reported greater difficulties with EFs in daily activities than those of hearing children. Correlation analysis between EFs and language showed significant levels only in the deaf group, especially in relation to meta-cognitive EFs. The results are discussed in terms of the role of early parent–child interaction and the relevance of EFs for everyday conversational situations.

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the key vector insect transmitting the Candidatus Liberibacter asiaticus (CLas) bacterium that causes the devastating citrus greening disease (Huanglongbing, HLB) worldwide. The D. citri salivary glands (SG) exhibit an important barrier against the transmission of HLB pathogen. However, knowledge on the molecular mechanism of SG defence against CLas infection is still limited. In the present study, we compared the SG transcriptomic response of CLas-free and CLas-infected D. citri using an illumine paired-end RNA sequencing. In total of 861 differentially expressed genes (DEGs) in the SG upon CLas infection, including 202 upregulated DEGs and 659 downregulated DEGs were identified. Functional annotation analysis showed that most of the DEGs were associated with cellular processes, metabolic processes, and the immune response. Gene ontology and Kyoto Encyclopaedia of Genes and Genomes enrichment analyses revealed that these DEGs were enriched in pathways involving carbohydrate metabolism, amino acid metabolism, the immune system, the digestive system, the lysosome, and endocytosis. A total of 16 DEGs were randomly selected to further validate the accuracy of RNA-Seq dataset by reverse-transcription quantitative polymerase chain reaction. This study provides substantial transcriptomic information regarding the SG of D. citri in response to CLas infection, which may shed light on the molecular interaction between D. citri and CLas, and provides new ideas for the prevention and control of citrus psyllid.

Interaction between n-butylammonium (BA) chloride and vermiculite from Santa Olalla (Spain) has been studied in large flake (5 × 5 × 0.1 mm) or ground powder (≤80 µm) samples. The differences in adsorption and decomposition of BA ions in both particle sizes have been established. In the interlamellar space, the BA ion remains unaltered in powder samples, but is degraded in flakes. The experimental results suggest decomposition of the BA in the interlamellar space of vermiculite flakes by breaking of the C-N bond. The degradation of BA takes place over a short period. The variety with BA in the interlamellar space is transformed into a new one, due to the degradation of alkylammonium. The transformation occurs through an interstratified phase formed between BA-vermiculite and NH4-vermiculite, and finally a phase appears in which only ammonium is present in the interlamellar space. Due to the many industrial applications of alkylammonium-clays, determination of the stability of alkylammonium in the interlamellar space of clay minerals is of great importance.

Interactions with bentonite are important in the chemical speciation and fate of heavy metals in soils and other ecosystems. The interactions of Zn with bentonite were studied using X-ray diffraction (XRD), dehydration, kinetic and sequential extraction procedures. The species and activity of Zn retained by bentonite were affected markedly by pH. The Zn(OH)+ was retained by bentonite prepared at pH ≥ 6.9. The extent of dehydration of Zn(OH)+-bentonite was higher than that for Zn-bentonite. At a relative humidity of 55.5%, the basal spacing of the Zn(OH)+-bentonite was from 1.21 to 1.26 nm with 1 water sheet and that of the Zn-bentonite was 1.51 nm with 2 water sheets. The greater affinity of Zn(OH)+ for bentonite than Zn was associated with a lower degree of hydration. When an aqueous suspension of Ca-bentonite was incubated with soluble Zn, the concentration of Zn retained by the Ca-bentonite was linearly related to the square root of time. The rate of the interaction was controlled probably by the interlayer diffusion and subsequently by the diffusion into the ditrigonal cavities in bentonite. The Zn retained by bentonite was dehydrated in situ so as to increase the bonding of Zn with surfaces of bentonite. With hydrothermal treatment the retained Zn could diffuse easily into the cavities and transform increasingly to the residual forms that are associated with the entrapped form.

The Mg-vermiculite from Santa Olalla has been treated with aliphatic amides—formamide (FM), acetamide (AM) and propionamide (PM)—in aqueous solution. These treatments produce the transformation towards NH4-vermiculite and interstratified NH4-vermiculite-Mg-vermiculite phases. The NH4-vermiculite, Mg-vermiculite and interstratified (mixed-layer) phases have been identified from basal X-ray diffraction (XRD) interval peaks between 10.3 Å and 14.4 Å, and confirmed by direct Fourier transform method, as well as by atomic absorption spectrometry (AAS), infrared (IR) spectroscopy and thermal analysis.

According to their NH4-vermiculite/Mg-vermiculite probability coefficients ratio (PA/PB), and PAA, these interstratified phases can be divided into 3 categories: 1) If the PA/PB ratio is ≥ 7/3 and PAA ≥ 0.7, there are interstratified phases with a strong tendency toward segregation (case of FM, AM and PM). 2) If the PA/PB ratio is between 5/5 and 6/4, with PAA in the range 0.45–0.6, there are nearly regular alternating and random interstratified phases (case of AM and PM). 3) If the PA/PB ratio is ≤ 5/5 and PAA ≤ 0.45, there are interstratified phases with a strong tendency toward alternation (case of PM).

Experimental evidence reported in the present work indicates that the mechanism of interaction of Mg-vermiculite with FM, AM and PM in an aqueous medium takes place by ion exchange of NH4 between the layers. The hydrolysis of these aliphatic amides leads to the liberation of NH4+ into the medium. It has been found that the NH4+ sorption depends on the physico-chemical characteristics of the particular aliphatic amide, and the transformation of Mg-vermiculite to interstratified and/or NH4-vermiculite phases depends on the amide concentration. These treatments allow one to control the formation of interstratified and NH4-vermiculite phases.

Acanthocephalans constitute a small taxonomic group related to rotifers and specialized in a parasitic lifestyle. Anurans act as paratenic and definitive hosts and infections always occur trophically. Our objective is to describe and summarize the richness of acanthocephalans in Neotropical anurans. We conducted a literature review in the main research databases, compiling data published until August 2021. We identified 66 articles with records of acanthocephalan-anuran association, 53.03% were carried out in Brazil. We detected 108 species of anurans from 11 families parasitized by acanthocephalans. With the exception of Bufonidae, Hylidae and Leptodactylidae, which are relatively well-studied families, interaction with acanthocephalans remains largely unexplored for most anuran species. We found six families of acanthocephalans: Centrorhynchidae, Echinorhynchidae, Oligacanthorhynchidae, Cavisomidae, Neoechinorhynchidae and Plagiorhynchidae. Centrorhynchidae and Echinorhynchidae presented the largest number of taxa associated with anurans. The largest number of records corresponded to acanthocephalans in the larval stage (cystacanths), for which anurans act as paratenic hosts. We observed a lack of specific taxonomic resolution in the identifications of most reports, because a large part of the records in the larval stage make morphological identification difficult. Brazil, Mexico, Paraguay, Argentina, Ecuador and Peru are the countries with the most records, while Costa Rica, Venezuela, Colombia, Chile and Uruguay exhibited the lowest publication numbers, resulting in gaps in the distribution of acanthocephalans. We expanded the known number of anuran species parasitized by acanthocephalans, compared to the last published review. Overall, we aim to contribute to the understanding of diversity within this intriguing but understudied group.

When the colonists who made up the Virginia Company of London established James Fort on the banks of the James River in 1607, they brought with them sheets of scrap copper. Based in large part on the experience of the earlier Roanoke Colony, the English knew that copper was a highly prized material among Native peoples of the Chesapeake, and they brought it with them as a trade item. Artifacts made from European smelted copper (impure copper and copper alloy) have been found at contact period sites (ca. AD 1607–1680) throughout Virginia, and James Fort has long been hypothesized to be the primary distribution point for that material. To test this hypothesis, we analyzed the elemental composition of a sample of smelted copper artifacts from James Fort (1607–ca. 1625), as well as samples of copper artifacts from five Native sites in central Virginia. We also analyzed a sample of copper artifacts from another well-known European fort site—Fort San Juan (1567–1568) in North Carolina. The results suggest that although a portion of the smelted copper that circulated through Native networks in Virginia came from James Fort, the rest of it possibly came from English, French, or Dutch distribution points to the northeast.

The purpose of this article is to investigate the interactional strategies that secondary school EFL learners use during telecollaboration with interlocutors from a different cultural and linguistic background. Its novelty lies in the educational level and cultural contexts explored as well as in the goal of examining whether frequency of strategy use may depend on the interlocutor and, if so, what the relevant factors are for such variation. The study focuses on two projects in which 10 participants from one Bulgarian school and 18 partners from two schools in Spain took part in dyadic synchronous videoconferences discussing culture-related topics. Data were collected via video recordings, field observations, semi-structured interviews, and questionnaires. The article presents both descriptive statistics and qualitative analysis of the communicative behavior of three case study students interacting with different telecollaborative partners. We found that the participants demonstrate differences in interactional behavior and utilize strategies with varying frequency depending on their interlocutor. The results also reveal crucial factors in the design of telecollaborative educational projects if learners are to successfully implement skills of discovery and interaction in real time.