Potential nursing effects of Parkia platycephala Benth. (Fabaceae) in a disturbed Brazilian Savanna area undergoing restoration

We evaluated the influence of Parkia platycephala on plant assemblages under its crown and surrounding areas in a disturbed Brazilian Savanna, as well as the effects of aqueous extracts of its leaves on the germination and development of three species, under the hypothesis that P. platycephala might work as a nurse species. Eleven areas of direct (ADIs) and indirect (AIIs) influence of P. platycephala and 11 control areas (COs) were delineated. All tree and shrub species present in these areas, including seedlings, were sampled. Richness, composition and abundance of woody taxa were determined. Laboratory studies analyzed the effects of P. platycephala aqueous leaf extracts on the germination and initial development of Dipteryx alata, Enterolobium gummiferum and Magonia pubescens, which in the field exhibited different abundance levels under its crown. Regarding plant assemblages, no differences in terms of richness and abundance of woody taxa were detected among the areas. However, we recorded a gradient of species composition and abundance ranks from ADI to CO areas. The number of seedlings also differed, with higher values near P. platycephala. Soil characteristics were similar among areas, but shading, plant height and diameter differed. The aqueous leaf extract at 25% provided the best germination of M. pubescens. The extract at 75% favored the initial development of this species in terms of root length. These results indicate that the presence of P. platycephala affects the structure of neighboring plant assemblages, possibly working as a facilitator for some species in areas undergoing restoration.

Tardigrades and Their Emergence as Model Organisms

Experimentally tractable organisms like C. elegans, Drosophila, zebrafish, and mouse are popular models for addressing diverse questions in biology. In 1997, two of the most valuable invertebrate model organisms to date – C. elegans and Drosophila – were found to be much more closely related to each other than expected. C. elegans and Drosophila belong to the nematodes and arthropods respectively, and these two phyla and six other phyla make up a clade of molting animals referred to as the Ecdysozoa. The other ecdysozoan phyla could be valuable models for comparative biology, taking advantage of the rich and continual sources of research findings as well as tools from both C. elegans and Drosophila. But when the Ecdysozoa was first recognized, few tools were available for laboratory studies in any of these six other ecdysozoan phyla. In 1999 I began an effort to develop tools for studying one such phylum, the tardigrades. Here, I describe how the tardigrade species Hypsibius exemplaris and tardigrades more generally have emerged over the past two decades as valuable new models for answering diverse questions. To date, these questions have included how animal body plans evolve and how biological materials can survive some remarkably extreme conditions.

Gangrenous Cholecystitis From Gallbladder Volvulus With a Hiatal Hernia

Gallbladder volvulus is a rare condition involving the rotation of the gallbladder about the cystic duct and vascular pedicle, compromising biliary drainage and blood flow. This report describes a case of gallbladder volvulus presenting in an 88-year-old female with acute onset of right upper quadrant abdominal pain, nausea, and vomiting. Complete work-up included a physical exam, laboratory studies, and computed tomography (CT), which was notable for a markedly distended gallbladder with circumferential wall thickening, pericholecystic fluid, a 12 mm common bile duct, and a hiatal hernia. Given that her initial presentation was consistent with acute cholecystitis, we elected to perform laparoscopic cholecystectomy. The definitive diagnosis of gallbladder volvulus was made intraoperatively after decompression of the gallbladder and visualization of counterclockwise rotation of the gallbladder around the hilum and the infundibulum. This case illustrates the challenge in preoperative diagnosis of gallbladder volvulus, which requires high clinical suspicion to provide prompt surgical intervention.

Feasibility of a Home-Based Task-Switching Training in Middle-Aged Caregivers

The current study aimed at investigating feasibility of a self-administered task-switching training in a middle-aged working population. Eighty-one caregivers (41–62 years old) were instructed to train at home 8 times either within a 7- or 14-day interval. Only 56.7% performed more than 50% of the instructed number of training sessions. However, compliant caregivers (who completed more than 4 training sessions) showed significant training gains and transfer to an untrained task-switching task. Although transfer effects to other cognitive tasks were not found, trained participants tended to report fewer everyday memory failures than a control group. In conclusion, the implementation of a home-based task-switching training in everyday life of caregivers is possible. However, there is only limited evidence for generalization of results of previous laboratory studies. Adherence and transfer to other cognitive tasks are discussed as important challenges in conveying laboratory findings into real life.

High Accuracy Molecular Line Lists for Studies of Exoplanets and Other Hot Atmospheres

The desire to characterize and model the atmospheres of the many extrasolar planets that have been discovered over the last three decades is a major driver of current astronomy. However, this goal is impacted by the lack of spectroscopic data on the molecules in question. As most atmospheres that can be studied are hot, some surprisingly so, this activity requires spectroscopic information not readily available from laboratory studies. This article will review the current status of available molecular spectroscopic data, usually presented as line lists, for studies of exoplanet atmospheres and, indeed, the atmospheres of other astronomical objects hotter than the Earth such as brown dwarfs, cool stars and even sunspots. Analysis of exoplanet transit spectra and the calculation of the relevant opacities often require huge datasets comprising billions of individual spectroscopic transitions. Conversely, the newly-developed high-resolution Doppler-shift spectroscopy technique has proved to be a powerful tool for detecting molecular species in exoplanet atmospheres, but relies on the use of smaller, highly accurate line lists. Methods of resolving issues arising from the competing demands of completeness versus accuracy for line lists are discussed.

Geomechanical properties of carbonate reservoir rocks and middle carbon cap rocks of the Ivinskoe oilfield

Laboratory studies of the geomechanical properties of rocks are an important and integral part in building a geomechanical model. This study resulted in a set of data on geomechanical and elastic properties of the rocks that compose the lower part of the Middle Carboniferous section of the Ivinskoye oilfield (Russia). Relationships between various elastic parameters were also established. The distribution of geomechanical properties correlates with structural/textural features of the rocks under study and their lithological type. This information can be used as a basis for geomechanical modeling and in preparation for hydraulic fracturing. Keywords: geomechanics; elastic properties; carbonate rock; laboratory core studies.

Conceptual Approaches to Solving the Issue of Reinforcing the Rock - Cut Structures of Geghard Monastery Complex

The article presents a visual and instrumental research of the technical condition of the main rock-cut structures and their masonry additions, the documentation of their damages (cracks, crevices, destructions and erosions) and deformations, thorough complete laboratory studies of rock samples and their physical and mechanical characteristics, conceptual approaches to preventive and reinforcing measures necessary for the further safe survival of structures, as well as the comprehensive development and implementation of measures to prevent further damages (elimination of causes) and ensure the long-term existence of structures. Based on the analyses carried out, it is recommended to use a ready-made dry mixture mortar of the “Mapegrout'' brand produced by the Italian company “Mapei” to fill cracks if necessary. It is available in the market of the country and is successfully used in the reconstruction of tunnels and other underground structures. The issues of compatibility of reinforcing materials with sandstone rock are also considered on the basis of some averaged data of the main decisive physical and mechanical characteristics of the strength and deformation of sandstone.

Symbolic Signal Use in Wild Chimpanzee Gestural Communication?: A Theoretical Framework

Symbolic communication is not obvious in the natural communicative repertoires of our closest living relatives, the great apes. However, great apes do show symbolic competencies in laboratory studies. This includes the understanding and the use of human-provided abstract symbols. Given this evidence for the underlying ability, the apparent failure to make use of it in the wild is puzzling. We provide a theoretical framework for identifying basic forms of symbolic signal use in chimpanzee natural communication. In line with the laboratory findings, we concentrate on the most promising domain to investigate, namely gesture, and we provide a case study in this area. We suggest that evidence for basic symbolic signal use would consist of the presence of two key characteristics of symbolic communication, namely arbitrariness and conventionalization. Arbitrariness means that the linkage between the form of the gesture and its meaning shows no obvious logical or otherwise motivated connection. Conventionalization means that the gesture is shared at the group-level and is thus socially learned, not innate. Further, we discuss the emergence and transmission of these gestures. Demonstrating this basic form of symbolic signal use would indicate that the symbolic capacities revealed by laboratory studies also find their expression in the natural gestural communication of our closest living relatives, even if only to a limited extent. This theoretical article thus aims to contribute to our understanding of the developmental origins of great ape gestures, and hence, arguably, of human symbolic communication. It also has a very practical aim in that by providing clear criteria and by pointing out potential candidates for symbolic communication, we give fieldworkers useful prerequisites for identifying and analyzing signals which may demonstrate the use of great apes’ symbolic capacities in the wild.

Laboratory studies of heated Bulk Fill composite in the tooth cavity during filling of teeth with carious defects

Aim. To study with the help of a microscope the marginal fit of Bulk-Fill group composite materials to the hard tissues of the tooth. Optimize the method of heating the composite in the cavity.Materials and methods. The marginal fit of the composite material of the Bulk-Fill group, sealed in 30 teeth of chewing anatomical and functional accessories extracted according to various indications, was studied. Materials used in the laboratory experiment: 3M ESPE Filtek posterior restorative Bulk Fill, SDR (Dentsply Sirona), Sonic Fill (Kerr). According to the manufacturers, the materials are used with the method of single-portion sealing. The research was conducted at the Department of General Dentistry of the S.M.Kirov Military Medical Academy of the Ministry of Defense of the Russian Federation.Results. 30 teeth extracted according to various indications of chewing anatomical and functional accessories were indicators were shown by the Sonic Fill (Kerr) system, due to heating and changing the viscosity of the material.Conclusions. It was proved in the laboratory that the heated composites of the Bulk-Fill group had the best edge fit during sealing than composites at normal room temperature. A nozzle was developed for heating the composite in the tooth cavity (priority application No. 2021120658 dated 12.07.2021).