What is Psychology's Role with New Neuroimmunology Findings?

In our graduate level, Doctoral training we are provided with a Biological Bases of Behavior course and sometimes an elective to take an advanced seminar in Neuroscience. With this training, we discover the impact of our biological functioning on behavior. Newest in this focus is the area of Neuroimmunology. The ways in which the body utilizes adaptive and cellular defenses against bacteria, viruses, prion and other toxins in one general facet of the field of Immunology. Recently in media sources, new hypotheses of the role of dysfunctional immune system functioning thus allowing a type of brain virus has been hypothesized with the disorder of Schizophreni

Refining self-propelled particle models for collective behaviour

Swarming, schooling, flocking and herding are all names given to the wide variety of collective behaviours exhibited by groups of animals, bacteria and even individual cells. More generally, the term swarming describes the behaviour of an aggregate of agents (not necessarily biological) of similar size and shape which exhibit some emergent property such as directed migration or group cohesion. In this paper we review various individual-based models of collective behaviour and discuss their merits and drawbacks. We further analyse some one-dimensional models in the context of locust swarming. In specific models, in both one and two dimensions, we demonstrate how varying the parameters relating to how much attention individuals pay to their neighbours can dramatically change the behaviour of the group. We also introduce leader individuals to these models with the ability to guide the swarm to a greater or lesser degree as we vary the parameters of the model. We consider evolutionary scenarios for models with leaders in which individuals are allowed to evolve the degree of influence neighbouring individuals have on their subsequent motion

Improved glycerol utilization by a triacylglycerol-producing Rhodococcus opacus strain for renewable fuels

Background: Glycerol generated during renewable fuel production processes is potentially an attractive substrate for the production of value-added materials by fermentation. An engineered strain MITXM-61 of the oleaginous bacterium Rhodococcus opacus produces large amounts of intracellular triacylglycerols (TAGs) for lipid-based biofuels on high concentrations of glucose and xylose. However, on glycerol medium, MITXM-61 does not produce TAGs and grows poorly. The aim of the present work was to construct a TAG-producing R. opacus strain capable of high-cell-density cultivation at high glycerol concentrations. Results: An adaptive evolution strategy was applied to improve the conversion of glycerol to TAGs in R. opacus MITXM-61. An evolved strain, MITGM-173, grown on a defined medium with 16 g L[superscript −1] glycerol, produced 2.3 g L[superscript −1] of TAGs, corresponding to 40.4% of the cell dry weight (CDW) and 0.144 g g[superscript −1] of TAG yield per glycerol consumed. MITGM-173 was able to grow on high concentrations (greater than 150 g L[superscript −1]) of glycerol. Cultivated in a medium containing an initial concentration of 20 g L[superscript −1] glycerol, 40 g L[superscript −1] glucose, and 40 g L[superscript −1] xylose, MITGM-173 was capable of simultaneously consuming the mixed substrates and yielding 13.6 g L[superscript −1] of TAGs, representing 51.2% of the CDM. In addition, when 20 g L[superscript −1] glycerol was pulse-loaded into the culture with 40 g L[superscript −1] glucose and 40 g L[superscript −1] xylose at the stationary growth phase, MITGM-173 produced 14.3 g L[superscript −1] of TAGs corresponding to 51.1% of the CDW although residual glycerol in the culture was observed. The addition of 20 g L[superscript −1] glycerol in the glucose/xylose mix resulted in a TAG yield per glycerol consumed of 0.170 g g[superscript −1] on the initial addition and 0.279 g g[superscript −1] on the pulse addition of glycerol. Conclusion: We have generated a TAG-producing R. opacus MITGM-173 strain that shows significantly improved glycerol utilization in comparison to the parental strain. The present study demonstrates that the evolved R. opacus strain shows significant promise for developing a cost-effective bioprocess to generate advanced renewable fuels from mixed sugar feedstocks supplemented with glycerol.Sweetwater Energy, Inc.MIT Energy Initiativ

Ergodic directional switching in mobile insect groups

We obtain a Fokker-Planck equation describing experimental data on the collective motion of locusts. The noise is of internal origin and due to the discrete character and finite number of constituents of the swarm. The stationary probability distribution shows a rich phenomenology including non-monotonic behavior of several order/disorder transition indicators in noise intensity. This complex behavior arises naturally as a result of the randomness in the system. Its counterintuitive character challenges standard interpretations of noise induced transitions and calls for an extension of this theory in order to capture the behavior of certain classes of biologically motivated models. Our results suggest that the collective switches of the group's direction of motion might be due to a random ergodic effect and, as such, they are inherent to group formation.Comment: Physical Review Focus 26, July 201

F-term uplifting via consistent D-terms

The issue of fine-tuning necessary to achieve satisfactory degree of hierarchy between moduli masses, the gravitino mass and the scale of the cosmological constant has been revisited in the context of supergravities with consistent D-terms. We have studied (extended) racetrack models where supersymmetry breaking and moduli stabilisation cannot be separated from each other. We show that even in such cases the realistic hierarchy can be achieved on the expense of a single fine-tuning. The presence of two condensates changes the role of the constant term in the superpotential, W_0, and solutions with small vacuum energy and large gravitino mass can be found even for very small values of W_0. Models where D-terms are allowed to vanish at finite vevs of moduli fields - denoted `cancellable' D-terms - and the ones where D-terms may vanish only at infinite vevs of some moduli - denoted `non-cancellable' - differ markedly in their properties. It turns out that the tuning with respect to the Planck scale required in the case of cancellable D-terms is much weaker than in the case of non-cancellable ones. We have shown that, against intuition, a vanishing D-term can trigger F-term uplifting of the vacuum energy due to the stringent constraint it imposes on vacuum expectation values of charged fields. Finally we note that our models only rely on two dimensionful parameters: M_P and W_0.Comment: 10 pages, 2 figures, plain Latex, references adde

Ferryl and Ferrate Species: Mössbauer Spectroscopy Investigation

High-valent iron species of oxidation states +4, +5, and +6, have been involved as intermediates in enzymatic reactions, in green organic synthesis, and in purification and disinfection of water. Many of these species have been synthesized to understand their role in different systems, which include ferryl complexes (oxoiron(IV) (Fe^IV=O), oxoiron(V) (Fe^V=O)), iron(IV / V / VI)-nitride complexes, and ferrates ((Fe^VIO₄^2–, Fe(VI), Fe^VO₄^3–, Fe(V), and Fe^IVO₄^4–, Fe(IV)). Ferryl and iron-nitride complexes have organic ligands surrounded at the iron center and are soluble in non-aqueous solvent. Comparatively, ferrate species are tetraoxyanions and are soluble in water. This paper presents Mössbauer spectroscopy as a tool to distinguish different oxidation states of iron and to gain information on the geometry and structure of high-valent iron complexes. Examples are given to demonstrate the application of Mössbauer spectroscopy in learning mechanisms of thermal decomposition of ferrates, encapsulation of heavy metals by ferrates, and oxidation of thiols by ferrates

High-frequency characterization of Permalloy nanosized strips using network analyzer ferromagnetic resonance

We report on the dynamic properties of Permalloy nanostrips at gagahertz frequencies. The thickness of the strips is 100 nm, strip width is 300 nm, strip spacing is 1 μm, and length is 0.3–100 μm; aspect ratios are 1:1, 1:2, 1:3, 1:5, 1:10, and 1:333. The dynamic behavior was studied by network analyzer ferromagnetic resonance (FMR) using Permalloy strips on a coplanar waveguide in flip-chip geometry. The FMR mode frequencies (fr) can be controlled by the aspect ratio as well as by the applied magnetic field (H). In longer strips (1:10 and 1:333), the excitation frequencies show a soft mode behavior (Heff = 990 Oe) when the field is along the hard axis. However, along the easy axis (along the strip length), fr increases with applied field. At a field of 3 kOe, fr values are almost independent of aspect ratio along the easy axis except for the 1:1 strip. Along the hard axis, the frequencies are strongly dependent upon the aspect ratio. We also observed that the frequency linewidths of the strips are dependent on the aspect rati