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Translating the surging interest in neuromorphic electronic components, such as those based on nonlinearities near Mott transitions, into large-scale commercial deployment faces steep challenges in the current lack of means to identify and design key material parameters. These issues are exemplified by the difficulties in connecting measurable material properties to device behavior via circuit element models. Here, the principle of local activity is used to build a model of VO

Future-generation neuromorphic computing seeks to overcome the limitations of von Neumann architectures by colocating logic and memory functions, thereby emulating the function of neurons and synapses in the human brain. Despite remarkable demonstrations of high-fidelity neuronal emulation, the predictive design of neuromorphic circuits starting from knowledge of material transformations remains challenging. VO

Transformations between different atomic configurations of a material oftentimes bring about dramatic changes in functional properties as a result of the simultaneous alteration of both atomistic and electronic structure. Transformation barriers between polytypes can be tuned through compositional modification, generally in an immutable manner. Continuous, stimulus-driven modulation of phase stabilities remains a significant challenge. Utilizing the metal-insulator transition of VO

The gene designated BAB1_1460 in the Brucella abortus 2308 genome sequence is predicted to encode the manganese transporter MntH. Phenotypic analysis of an isogenic mntH mutant indicates that MntH is the sole high-affinity manganese transporter in this bacterium but that MntH does not play a detectable role in the transport of Fe 2+ , Zn 2+ , Co 2+ , or Ni 2+ . Consistent with the apparent selectivity of the corresponding gene product, the expression of the mntH gene in B. abortus 2308 is repressed by Mn 2+ , but not Fe 2+ , and this Mn-responsive expression is mediated by a Mur-like repressor. The B. abortus mntH mutant MWV15 exhibits increased susceptibility to oxidative killing in vitro compared to strain 2308, and a comparative analysis of the superoxide dismutase activities present in these two strains indicates that the parental strain requires MntH in order to make wild-type levels of its manganese superoxide dismutase SodA. The B. abortus mntH mutant also exhibits extreme attenuation in both cultured murine macrophages and experimentally infected C57BL/6 mice. These experimental findings indicate that Mn 2+ transport mediated by MntH plays an important role in the physiology of B. abortus 2308, particularly during its intracellular survival and replication in the host.

Meditation practices may impact physiological pathways that are modulated by stress and relevant to disease. While much attention has been paid to meditation practices that emphasize calming the mind, improving focused attention, or developing mindfulness, less is known about meditation practices that foster compassion. Accordingly, the current study examined the effect of compassion meditation on innate immune, neuroendocrine and behavioral responses to psychosocial stress and evaluated the degree to which engagement in meditation practice influenced stress reactivity. Sixty-one healthy adults were randomized to 6 weeks of training in compassion meditation (n=33) or participation in a health discussion control group (n=28) followed by exposure to a standardized laboratory stressor (Trier social stress test [TSST]). Physiologic and behavioral responses to the TSST were determined by repeated assessments of plasma concentrations of interleukin (IL)-6 and cortisol as well as total distress scores on the Profile of Mood States (POMS). No main effect of group assignment on TSST responses was found for IL-6, cortisol or POMS scores. However, within the meditation group, increased meditation practice was correlated with decreased TSST-induced IL-6 (r(p)=-0.46, p=0.008) and POMS distress scores (r(p)=-0.43, p=0.014). Moreover, individuals with meditation practice times above the median exhibited lower TSST-induced IL-6 and POMS distress scores compared to individuals below the median, who did not differ from controls. These data suggest that engagement in compassion meditation may reduce stress-induced immune and behavioral responses, although future studies are required to determine whether individuals who engage in compassion meditation techniques are more likely to exhibit reduced stress reactivity.

Brucella abortus 2308 derivatives with mini-Tn 5 insertions in purE , purL , and purD display significant attenuation in the BALB/c mouse model, while isogenic mutants with mini-Tn 5 insertions in pheA , trpB , and dagA display little or no attenuation in cultured murine macrophages or mice. These experimental findings confirm the importance of the purine biosynthesis pathways for the survival and replication of the brucellae in host macrophages. In contrast to previous reports, however, these results indicate that exogenous tryptophan and phenylalanine are available for use by the brucellae in the phagosomal compartment.

The purpose of this paper is to analyze and suggest possible roles for special operations forces in homeland security and homeland defense. The paper reviews the obstacles to the use of military forces in the domestic environment under the Posse Comitatus Act of 1878 and then introduces special operations and special operations forces competencies. The paper then analyzes the current National Strategy for Homeland Security and injects suggestions for using special operations forces to bolster the Strategy. After an overview of United States Northern Command, the Department of Defense's supported command for the homeland defense mission, the paper recommends establishing a sub-unified organization under Northern Command to provide special operations command and control, planning, and mission execution. Underlying the entire discussion is the critical need to incorporate special operations forces early in the campaign plan, rather than waiting for mission execution to blend them into the force structure. Regardless of the role special operations forces play or the structure that exercises their command and control, commanders will reap the benefits these highly specialized forces provide only if they understand who they are, what they do, and how to integrate them into the missions of homeland security and homeland defense.