Biology

During adolescence, the brain is highly susceptible to alcohol-induced damage and subsequent neuroimmune responses, effects which may enhance development of an alcohol use disorder (AUD). Neuroimmune reactions are implicated in adolescent alcohol exposure escalating adulthood drinking. Therefore, we investigated whether intermittent alcohol exposure in male, adolescent rats (AIE) escalated adult drinking via two-bottle choice (2BC). We also examined the influence of housing environment across three groups: standard (group-housed with enrichment during 2BC), impoverished (group-housed without enrichment during 2BC), or isolation (single-housed without bedding or enrichment throughout). In the standard group immediately after AIE/saline and after 2BC, we also examined the expression of microglial marker, Iba1, reactive astrocyte marker, vimentin, and neuronal cell death dye, FluoroJade B (FJB). We did not observe an escalation of adulthood drinking following AIE, regardless of housing...

The massive spawning of anchovy (Engraulis anchoita) in Argentine waters takes place in spring in the coastal sector off the Buenos Aires Province, with the highest concentrations of spawners occurring in front of the Río de la Plata mouth. In October 1995, the size structure, composition and abundance of the zooplankton community was analyzed and related to the hydrography and the abundance of anchovy eggs. Oceanographic conditions were different from the recorded means for the season. A higher proportion of the colder and more saline shelf waters were present in the coastal area and strong haloclines were not observed. High values of plankton biomass were observed in the estuarine frontal area and in the weakly stratified waters of the median shelf. The cluster analysis of the stations gave rise to the formation of coastal (CA), transitional (TA) and shelf (SA) faunistic areas. Mesozooplankton smaller than 1 mm total length (TL) dominated the whole area. The copepods, Paracalanus spp. and Oithona similis, and the cladocerans, Evadne nordmanni and Podon spp., constituted the bulk of this mesozooplankton fraction. Oithona similis was the dominant species in the SA. The copepod, Acartia tonsa (1–2 mm TL), was extremely abundant in the estuarine front (more than 17 600 individuals m–3) followed by appendicularians, members of Pseudocalanidae, anchovy eggs and decapod larvae. Species of Calanidae (Calanoides carinatus and Calanus simillimus), the amphipod hyperiid, Themisto gaudichaudii, and the euphausiid, Euphausia lucens, largely dominated the macrozooplankton…

The risk factors for relapse of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia after vancomycin treatment are unknown. Diversilab typing was used to classify recurrent bacteremia as relapse or reinfection. Bacteremia for >7 days and staphylococcal cassette chromosome mec element (SCC mec ) type II were independently associated with relapse of MRSA bacteremia after vancomycin treatment.

A recent examination of Palaeopisthacanthus schucherti Petrunkevitch revealed the presence of stigmata and lateral eyes, and the absence of any postabdomen in the available material. A new diagnosis of the genus and diagnosis and description of the species are given.

ABSTRACT While the state of the art has been described for recording bird songs and calls, there are no described best practices for collecting and preserving the avian vocal organ, the syrinx. In addition to skins and skeletal preparations, field collection of tissues for DNA sequencing has become a common practice. Protocols for such tissue collection often involve accessing internal organs. Here we argue that collecting syringes, which also involves accessing the chest cavity, adds only minimal time to field or skeletal preparation and can be done without damage to the skeleton. Collecting syringes will enable studies of structure–function relationships in the production of calls and song that have not been previously possible. Three-dimensional X-ray computed tomography (CT) imaging techniques allow new insight into these relationships, but material of both male and female birds as well as juveniles is lacking for most avian taxa. Here, we present a guide to the removal and preservation of the avian syrinx and associated vocal anatomy in hopes of increasing their representation in biological collections. In this guide, we suggest that taking in situ measurements is ideal since dissection, fixation, and tissue staining can affect measurements of certain airway features such as tracheal diameter and bronchial length. Our guidelines demonstrate that removing a single wing, shoulder, and half of the pectoral girdle from the dorsal side of the thorax along with disarticulating the sternal and vertebral rib segments on one side of the body allows exposure of the complete airway without damaging the skeleton. We also provide recommendations for fixation, storage, and staining of specimens in preparation for diffusible iodine-based contrast-enhanced computed tomography (diceCT) scans that allow imaging of both soft tissue structures such as vocal folds and muscles as well as the cartilaginous rings that support these structures.