Structural and functional characterization of dendritic arbors and GABAergic synaptic inputs on interneurons and principal cells in the rat basolateral amygdala

The basolateral amygdala (BLA) is a complex brain region associated with processing emotional states, such as fear, anxiety, and stress. Some aspects of these emotional states are driven by the network activity of synaptic connections, derived from both local circuitry and projections to the BLA from other regions. Although the synaptic physiology and general morphological characteristics are known for many individual cell types within the BLA, the combination of morphological, electrophysiological, and distribution of neurochemical GABAergic synapses in a three-dimensional neuronal arbor has not been reported for single neurons from this region. The aim of this study was to assess differences in morphological characteristics of BLA principal cells and interneurons, quantify the distribution of GABAergic neurochemical synapses within the entire neuronal arbor of each cell type, and determine whether GABAergic synaptic density correlates with electrophysiological recordings of inhibitory postsynaptic currents. We show that BLA principal neurons form complex dendritic arborizations, with proximal dendrites having fewer spines but higher densities of neurochemical GABAergic synapses compared with distal dendrites. Furthermore, we found that BLA interneurons exhibited reduced dendritic arbor lengths and spine densities but had significantly higher densities of putative GABAergic synapses compared with principal cells, which was correlated with an increased frequency of spontaneous inhibitory postsynaptic currents. The quantification of GABAergic connectivity, in combination with morphological and electrophysiological measurements of the BLA cell types, is the first step toward a greater understanding of how fear and stress lead to changes in morphology, local connectivity, and/or synaptic reorganization of the BLA.

DNase I Site Mapping and Micrococcal Nuclease Digestion of Pachytene Chromatin Reveal Novel Structural Features

A comparison of the DNase I digestion products of the 32P-5’-end-labeled pachytene nucleosome core particles (containing histones H2A, TH2A, X2, H2B, THPB, H3a, nd H4) and liver nucleosome core particles (containing somatic histones H2A, H2B, H3, and H4) revealed that the cleavage sites that are 30, 40, and 110 nucleotidesa way from the 5’-enda re significantly more accessiblei n the pachytene core particles than in the liver core particles. These cleavage sites correspond to the region wherein H2B interacts with the nucleosome core DNA. These results, therefore, suggest that the histone-DNA interactiona t these sites in the pachytene core particles is weaker, possibly because of the presence of the histone variant THBB interacting at similar topological positions in the nucleosome core as that of its somatic counterpart H2B. Such a loosened structumrea y also be maintainede ven in the native pachytene chromatin since micrococcal nuclease digestion of pachytene nuclei resulted in a higher ratio of subnucleosomes (SN4 + SN?) to mononucleosomes than that observed liinv er chromatin

Some features of solid propellant chemistry

Abstract is not available.

Preparation and catalytic studies of palladium nanoparticles stabilized by dendritic phosphine ligand-functionalized silica

Silica is a prominently utilized heterogeneous metal catalyst support. Functionalization of the silica with poly(ether imine) based dendritic phosphine ligand was conducted, in order to assess the efficacy of the dendritic phosphine in reactions facilitated by a silica supported metal catalyst. The phosphinated poly(ether imine) (PETIM) dendritic ligand was bound covalently to the functionalized silica. For this purpose, the phosphinated dendritic ligand containing an amine at the focal point was synthesized initially. Complexation of the dendritic phosphine functionalized silica with Pd(COD)Cl-2 yielded Pd(II) complex, which was reduced subsequently to Pd(0), by conditioning with EtOH. The Pd metal nanoparticle thus formed was characterized by physical methods, and the spherical nanoparticles were found to have >85% size distribution between 2 nm and 4 nm. The metal nanoparticle was tested as a hydrogenation catalyst of olefins. The catalyst could be recovered and recycled more than 10 times, without a loss in the catalytic efficiency.

The mechanisms of human renal epithelial cell modulation of autologous dendritic cell phenotype and function

Proximal tubule epithelial cells (PTEC) of the kidney line the proximal tubule downstream of the glomerulus and play a major role in the re-absorption of small molecular weight proteins that may pass through the glomerular filtration process. In the perturbed disease state PTEC also contribute to the inflammatory disease process via both positive and negative mechanisms via the production of inflammatory cytokines which chemo-attract leukocytes and the subsequent down-modulation of these cells to prevent uncontrolled inflammatory responses. It is well established that dendritic cells are responsible for the initiation and direction of adaptive immune responses. Both resident and infiltrating dendritic cells are localised within the tubulointerstitium of the renal cortex, in close apposition to PTEC, in inflammatory disease states. We previously demonstrated that inflammatory PTEC are able to modulate autologous human dendritic cell phenotype and functional responses. Here we extend these findings to characterise the mechanisms of this PTEC immune-modulation using primary human PTEC and autologous monocyte-derived dendritic cells (MoDC) as the model system. We demonstrate that PTEC express three inhibitory molecules: (i) cell surface PD-L1 that induces MoDC expression of PD-L1; (ii) intracellular IDO that maintains the expression of MoDC CD14, drives the expression of CD80, PD-L1 and IL-10 by MoDC and inhibits T cell stimulatory capacity; and (iii) soluble HLA-G (sHLA-G) that inhibits HLA-DR and induces IL-10 expression by MoDC. Collectively the results demonstrate that primary human PTEC are able to modulate autologous DC phenotype and function via multiple complex pathways. Further dissection of these pathways is essential to target therapeutic strategies in the treatment of inflammatory kidney disorders.

Significant features of the epidemiology of equine influenza in Queensland, Australia, 2007.

An outbreak of equine influenza (EI) caused by influenza A H3N8 subtype virus occurred in the Australian states of Queensland and New South Wales in August 2007. Infection in the Australian horse population was associated with the introduction of infection by horses from overseas. The first case of EI in Queensland was detected on 25 August 2007 at an equestrian sporting event. Infection subsequently spread locally and to other clusters through horse movements prior to the implementation of an official standstill. There were five main clusters of infected properties during this outbreak and several outliers, which were investigated to find the potential mechanism of disease spread. To contain the outbreak, Queensland was divided into infection status zones, with different movement controls applied to each zone. Vaccination was implemented strategically in infected areas and within horse subpopulations. Control and eventual eradication of EI from Queensland was achieved through a combination of quarantine, biosecurity measures, movement control, rapid diagnostic testing and vaccination.

A flexible hierarchical approach for facial age estimation based on multiple features

Age estimation from facial images is increasingly receiving attention to solve age-based access control, age-adaptive targeted marketing, amongst other applications. Since even humans can be induced in error due to the complex biological processes involved, finding a robust method remains a research challenge today. In this paper, we propose a new framework for the integration of Active Appearance Models (AAM), Local Binary Patterns (LBP), Gabor wavelets (GW) and Local Phase Quantization (LPQ) in order to obtain a highly discriminative feature representation which is able to model shape, appearance, wrinkles and skin spots. In addition, this paper proposes a novel flexible hierarchical age estimation approach consisting of a multi-class Support Vector Machine (SVM) to classify a subject into an age group followed by a Support Vector Regression (SVR) to estimate a specific age. The errors that may happen in the classification step, caused by the hard boundaries between age classes, are compensated in the specific age estimation by a flexible overlapping of the age ranges. The performance of the proposed approach was evaluated on FG-NET Aging and MORPH Album 2 datasets and a mean absolute error (MAE) of 4.50 and 5.86 years was achieved respectively. The robustness of the proposed approach was also evaluated on a merge of both datasets and a MAE of 5.20 years was achieved. Furthermore, we have also compared the age estimation made by humans with the proposed approach and it has shown that the machine outperforms humans. The proposed approach is competitive with current state-of-the-art and it provides an additional robustness to blur, lighting and expression variance brought about by the local phase features.

Dendritic structures produced on solidification of multicomponent aqueous solutions

Dendrite structures of ice produced on undirectional solidification of ternary and quaternary aqueous solutions have been studied. Upon freezing, solutions containing more than one solute produce plate-shaped dendrites of ice. The spacing between dendrites increase linearly with the distance from the chill surface and the square root of local solidification time (or square root of inverse freezing rate) for any fixed composition. For fixed freezing conditions, the dendrite spacings from multicomponent aqueous solutions were a function of the concentrations and diffusion coefficients of the individual solutes. The dendrite spacing produced by freezing of a solution was changed by the addition of a solute different from those already present. If the main diffusion coefficient of the added solute is higher than that of solutes already present, the dendrite spacing is increased and vice versa. The dendrite spacing in multi-component systems increases with the total solute concentration if the constituent solutes are present in equal amounts. The dendrite spacing obtained on freezing of these dilute multicomponent solutions can be expressed by regression equations of the type Image Full-size image (2K) where L is the dendrite spacing in microns, C1, C2 and C3 are concentrations of individual solutes, Θf is the total freezing time and A1 −A8 are constants. A Yates analysis of the dendrite spacings in a factorial design of quaternary solutions indicates that there are strong interactions between individual solutes in regard to their effect on the dendrite spacings. A mass transport analysis has been used to calculate the interdendritic supersaturation ΔC of the individual solutes, the supercooling in the interdendritic liquid ΔT, and the transverse growth velocity of the dendrites, VT. In ternary solutions if two solutes are present in equal amount the supersaturation of the solute with higher main diffusion coefficient is lower, and vice versa. If a solute with higher main diffusion coefficient is added to a binary solution, the interface growth velocity, the interdendritic supersaturation of the base solute and the interdendritic supercooling increase with the quantity of solute added.

Implications of geometric plasticity for maximizing photosynthesis in branching corals

Reef-building corals are an example of plastic photosynthetic organisms that occupy environments of high spatiotemporal variations in incident irradiance. Many phototrophs use a range of photoacclimatory mechanisms to optimize light levels reaching the photosynthetic units within the cells. In this study, we set out to determine whether phenotypic plasticity in branching corals across light habitats optimizes potential light utilization and photosynthesis. In order to do this, we mapped incident light levels across coral surfaces in branching corals and measured the photosynthetic capacity across various within-colony surfaces. Based on the field data and modelled frequency distribution of within-colony surface light levels, our results show that branching corals are substantially self-shaded at both 5 and 18 m, and the modal light level for the within-colony surface is 50 mu mol photons m(-2) s(-1). Light profiles across different locations showed that the lowest attenuation at both depths was found on the inner surface of the outermost branches, while the most self-shading surface was on the bottom side of these branches. In contrast, vertically extended branches in the central part of the colony showed no differences between the sides of branches. The photosynthetic activity at these coral surfaces confirmed that the outermost branches had the greatest change in sun- and shade-adapted surfaces; the inner surfaces had a 50 % greater relative maximum electron transport rate compared to the outer side of the outermost branches. This was further confirmed by sensitivity analysis, showing that branch position was the most influential parameter in estimating whole-colony relative electron transport rate (rETR). As a whole, shallow colonies have double the photosynthetic capacity compared to deep colonies. In terms of phenotypic plasticity potentially optimizing photosynthetic capacity, we found that at 18 m, the present coral colony morphology increased the whole-colony rETR, while at 5 m, the colony morphology decreased potential light utilization and photosynthetic output. This result of potential energy acquisition being underutilized in shallow, highly lit waters due to the shallow type morphology present may represent a trade-off between optimizing light capture and reducing light damage, as this type morphology can perhaps decrease long-term costs of and effect of photoinhibition. This may be an important strategy as opposed to adopting a type morphology, which results in an overall higher energetic acquisition. Conversely, it could also be that maximizing light utilization and potential photosynthetic output is more important in low-light habitats for Acropora humilis.

Robust features of future climate change impacts on sorghum yields in West Africa

West Africa is highly vulnerable to climate hazards and better quantification and understanding of the impact of climate change on crop yields are urgently needed. Here we provide an assessment of near-term climate change impacts on sorghum yields in West Africa and account for uncertainties both in future climate scenarios and in crop models. Towards this goal, we use simulations of nine bias-corrected CMIP5 climate models and two crop models (SARRA-H and APSIM) to evaluate the robustness of projected crop yield impacts in this area. In broad agreement with the full CMIP5 ensemble, our subset of bias-corrected climate models projects a mean warming of +2.8 °C in the decades of 2031–2060 compared to a baseline of 1961–1990 and a robust change in rainfall in West Africa with less rain in the Western part of the Sahel (Senegal, South-West Mali) and more rain in Central Sahel (Burkina Faso, South-West Niger). Projected rainfall deficits are concentrated in early monsoon season in the Western part of the Sahel while positive rainfall changes are found in late monsoon season all over the Sahel, suggesting a shift in the seasonality of the monsoon. In response to such climate change, but without accounting for direct crop responses to CO2, mean crop yield decreases by about 16–20% and year-to-year variability increases in the Western part of the Sahel, while the eastern domain sees much milder impacts. Such differences in climate and impacts projections between the Western and Eastern parts of the Sahel are highly consistent across the climate and crop models used in this study. We investigate the robustness of impacts for different choices of cultivars, nutrient treatments, and crop responses to CO2. Adverse impacts on mean yield and yield variability are lowest for modern cultivars, as their short and nearly fixed growth cycle appears to be more resilient to the seasonality shift of the monsoon, thus suggesting shorter season varieties could be considered a potential adaptation to ongoing climate changes. Easing nitrogen stress via increasing fertilizer inputs would increase absolute yields, but also make the crops more responsive to climate stresses, thus enhancing the negative impacts of climate change in a relative sense. Finally, CO2 fertilization would significantly offset the negative climate

Some Unique Features of Egg Laying and Reproduction in Ichthyophis Malabarensis (Taylor) (Apoda:Amphibia)

The paper describes egg laying and reproduction in ICHTHYOPHIS MALABARENSIS. 100 eggs, the largest ever in Apoda, are laid in a single string and manipulated by the female into a massive clutch. The reproductive strategies in the species are discussed.