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The basolateral amygdala (BLA) plays a vital role in associating sensory stimuli with salient valence information. Excitatory principal neurons (PNs) undergo plastic changes to encode this association; however, local BLA inhibitory interneurons (INs) gate PN plasticity via feedforward inhibition (FFI). Despite literature implicating parvalbumin expressing (PV+) INs in FFI in cortex and hippocampus, prior anatomical experiments in BLA implicate somatostatin expressing (Sst+) INs. The lateral entorhinal cortex (LEC), a brain region carrying olfactory information, projects to BLA where it drives FFI. In the present study, we asked whether LEC input mediates plasticity in BLA and explored the role of interneurons in this circuit. We combined patch clamp electrophysiology, chemogenetics, unsupervised cluster analysis, and predictive modeling and found that a previously unreported subpopulation of fast-spiking Sst+ INs mediate LEC→BLA FFI and gate plasticity. Our study raises the question whether this circuit is involved in plasticity in olfactory learning.

This paper presents the use of a novel through-transmission ultrasonic (TTU) Acoustography non-destructive evaluation (NDE) method to detect foreign object inclusion (FOI) defects in graphite epoxy composite laminates. The study employed three different composite test standards with varied size FOI defects embedded at varying depth within the composite laminates. For validation, Acoustography results were directly compared with conventional immersion TTU testing and infrared thermography (IRT) methods. From results obtained, it was demonstrated that the Signal-to-Noise Ratio (SNR) measurements for Acoustography were more than 6:1 and were in good correlation with immersion TTU and IRT results. The defect sizing ability of TTU Acoustography for FOI defects in graphite epoxy composite laminates were also in strong correlation with immersion TTU and IRT techniques. Finally, for the three laboratory systems employed in this study, typical panel TTU Acoustography inspection time was just about three minutes to scan a 300 mm × 300 mm (11.8″ × 11.8″) area, which was more than three times faster compared to IRT and sixty times faster to conventional immersion TTU C-Scan techniques. This is a very significant finding for the reason that Acoustography is being developed as a faster, more efficient, and affordable alternative to traditional ultrasonic inspection systems for composite manufacturing quality control and quality assurance (QC/QA) and field maintenance of composite structure applications.

Haploid microcysts and diploid microsclerotia of Physarum flavicomum Berk. are dormant phases of the life cycle surrounded by rigid cell walls. Microplasmodia are the actively growing diploid phase of the life cycle. Microplasmodia lack a cell wall but are covered by a constantly replenished slime coat which is secreted and accumulates in liquid growth medium. Chemical analyses of purified walls from microcysts and microsclerotia revealed the presence of polysaccharide, lipid, and protein as major components. The polysaccharide of microcyst walls was composed of galactosamine with smaller amounts of glucose, galactose, and ribose. The polysaccharide of microsclerotial walls was primarily composed of galactosamine, with small amounts of glucose and galactose. The slime coat of microplasmodia consisted of a galactose-containing polysaccharide and protein. The protein components of microcyst and microsclerotial walls and the slime coat protein had strikingly similar amino acid compositions. Lysine was present in the greatest quantity, with large amounts of aspartic acid, alanine, glutamic acid, and glycine; the sulfur amino acids occurred in the smallest proportion.

A temperature-programmed graphite microfurnace apparatus with mechanical stirring is described for the thermal regeneration of powdered activated carbon (PAC) alone or PAC-biological sludge mixtures from the PAC enhancement of the activated sludge process. Three PACs with widely differing BET areas were evaluated to determine the effects of regeneration on their physical and chemical properties. PAC weight % recoveries were in the range of 60–80%, and the recovery of wastewater (filtered mixed liquor) adsorption capacity regularly exceeded 100% for all carbons. In one case, 222% recovery was achieved. Regeneration always reduced BET area but the effects on I 2 number, pore size distribution and particle size were mixed. Compared to the regeneration of PAC alone, the presence of 40–50% biological sludge was clearly detrimental to the regeneration process. Nevertheless, essentially complete regeneration could be achieved with biomass present by adding a 20-min 400°C, N 2 -purge-gas charring step to the usual 20-min, 825°C, H 2 O-N 2 -CO 2 purge-gas reactivation step. Unfortunately, charring the biomass produced a regenerated material containing 27–34% inerts including carbonaceous char and mineral ash. This black inert material was quite insoluble in dilute HCl and had no useful adsorption capacity. The controlled application of H 2 O or trace amounts of O 2 during charring is suggested for the minimization of detrimental char but further research is needed.

Haploid myxamoebae-swarm cells of Physarum flavicomum , grown in semidefined medium, differentiated in a nonnutrient salts solution to produce dormant microcysts. Over 90% of the original cell population converted to microcysts after 72 h of incubation. The intracellular content of protein, neutral hexose and RNA decreased significantly during encystment, but the DNA content was relatively stable. A change in metabolic patterns occurred during differentiation since encysting cells, but not growing cells, actively catabolized protein amino acids. Whether encystment progressed or not was determined by the extracellular availability of certain amino acids. The condition of amino acid imbalance and not glucose availability initiated the differentiation of the vegetative cells to microcysts. Only the branched chain aliphatic amino acids, leucine, isoleucine, and valine (in that order), were significant determinants of the encystment process. The compounds which inhibited encystment also inhibited intracellular proteolysis. Radioactive amino acids were actively taken up from the salts solution by encysting cells and incorporated into protein. Proteins formed in the early stages of encystment were degraded to a certain extent as encystment proceeded. However, [ 14 C]leucine-labeled proteins produced by encysting cells were degraded and catabolized less than those labeled with [ 14 C]isoleucine and [ 14 C]valine.