The effects of arousal on apical amplification and conscious state

Neocortical pyramidal cells can integrate two classes of input separately and use one to modulate response to the other. Their tuft dendrites are electrotonically separated from basal dendrites and soma by the apical dendrite, and apical hyperpolarization-activated currents (Ih) further isolate subthreshold integration of tuft inputs. When apical depolarization exceeds a threshold, however, it can enhance response to the basal inputs that specify the cell’s selective sensitivity. This process is referred to as apical amplification (AA). We review evidence suggesting that, by regulating Ihin the apical compartments, adrenergic arousal controls the coupling between apical and somatic integration zones thus modifying cognitive capabilities closely associated with consciousness. Evidence relating AA to schizophrenia, sleep, and anesthesia is reviewed, and we assess theories that emphasize the relevance of AA to consciousness. Implications for theories of neocortical computation that emphasize context-sensitive modulation are summarized. We conclude that the findings concerning AA and its regulation by arousal offer a new perspective on states of consciousness, the function and evolution of neocortex, and psychopathology. Many issues worthy of closer examination arise

Photoionized plasma calculations using laboratory and astrophysical models

We present numerical simulations from the code GALAXY, frequently employed to model the distribution of excitation and ionization, and the spectral emission from laboratory plasma experiments. In particular, preliminary calculations relevant to the Lawrence Livermore National Laboratory photoionization collaboration are presented, along with results which compare GALAXY with results from the astrophysical code CLOUDY

Selective Complexation and Reactivity of Metallic Nitride and Oxometallic Fullerenes with Lewis Acids and Use as an Effective Purification Method

Metallic nitride fullerenes (MNFs) and oxometallic fullerenes (OMFs) react quickly with an array of Lewis acids. Empty-cage fullerenes are largely unreactive under conditions used in this study. The reactivity order is Sc4O2@Ih-C80 \u3e Sc3N@C78 \u3e Sc3N@C68 \u3e Sc3N@D5h-C80 \u3e Sc3N@Ih-C80. Manipulations of Lewis acids, molar ratios, and kinetic differences within the family of OMF and MNF metallofullerenes are demonstrated in a selective precipitation scheme, which can be used either alone for purifying Sc3N@Ih-C80 or combined with a final high-performance liquid chromatography pass for Sc4O2@Ih-C80, Sc3N@D5h-C80, Sc3N@C68, or Sc3N@C78. The purification process is scalable. Analysis of the experimental rate constants versus electrochemical band gap explains the order of reactivity among the OMFs and MNFs

First geodetic observations using new VLBI stations ASKAP-29 and WARK12M

We report the results of a successful 7 hour 1.4 GHz VLBI experiment using two new stations, ASKAP-29 located in Western Australia and WARK12M located on the North Island of New Zealand. This was the first geodetic VLBI observing session with the participation of these new stations. We have determined the positions of ASKAP-29 and WARK12M. Random errors on position estimates are 150-200 mm for the vertical component and 40-50 mm for the horizontal component. Systematic errors caused by the unmodeled ionosphere path delay may reach 1.3 m for the vertical component.Comment: 11 pages, 6 flgures, 4 table

We Can Change the Natural History of Type 2 Diabetes

As diabetes develops, we currently waste the first ∼10 years of the natural history. If we found prediabetes and early diabetes when they first presented and treated them more effectively, we could prevent or delay the progression of hyperglycemia and the development of complications. Evidence for this comes from trials where lifestyle change and/or glucose-lowering medications decreased progression from prediabetes to diabetes. After withdrawal of these interventions, there was no “catch-up”—cumulative development of diabetes in the previously treated groups remained less than in control subjects. Moreover, achieving normal glucose levels even transiently during the trials was associated with a substantial reduction in subsequent development of diabetes. These findings indicate that we can change the natural history through routine screening to find prediabetes and early diabetes, combined with management aimed to keep glucose levels as close to normal as possible, without hypoglycemia. We should also test the hypothesis with a randomized controlled trial

Multidrug-Resistant Organism Infections in US Nursing Homes: A National Study of Prevalence, Onset, and Transmission across Care Settings, October 1, 2010-December 31, 2011

Objective.To understand the prevalence of multidrug-resistant organism (MDRO) infections among nursing home (NH) residents and the potential for their spread between NHs and acute care hospitals (ACHs).Methods.Descriptive analyses of MDRO infections among NH residents using all NH residents in the Long-Term Care Minimum Data Set (MDS) 3.0 between October 1, 2010 and December 31, 2011.Results.Analysis of MDS data revealed a very high volume of bidirectional patient flow between NHs and ACHs, indicating the need to study MDRO infections in NHs as well as in hospitals. A total of 4.24% of NH residents had an active MDRO diagnosis on at least 1 MDS assessment during the study period. This rate significantly varied by sex, age, urban/rural status, and state. Approximately 2% of NH discharges to ACHs involved a resident with an active diagnosis of infection due to MDROs. Conversely, 1.8% of NH admissions from an ACH involved a patient with an active diagnosis of infection due to MDROs. Among residents who acquired an MDRO infection during the study period, 57% became positive in the NH, 41% in the ACH, and 2% in other settings (eg, at a private home or apartment).Conclusion.Even though NHs are the most likely setting where residents would acquire MDROs after admission to an NH (accounting for 57% of cases), a significant fraction of NH residents acquire MDRO infection at ACHs (41%). Thus, effective MDRO infection control for NH residents requires simultaneous, cooperative interventions among NHs and ACHs in the same community.</jats:sec

Herschel observations of EXtraordinary Sources: Analysis of the full Herschel/HIFI molecular line survey of Sagittarius B2(N)

A sensitive broadband molecular line survey of the Sagittarius B2(N) star-forming region has been obtained with the HIFI instrument on the Herschel Space Observatory, offering the first high-spectral resolution look at this well-studied source in a wavelength region largely inaccessible from the ground (625-157 um). From the roughly 8,000 spectral features in the survey, a total of 72 isotopologues arising from 44 different molecules have been identified, ranging from light hydrides to complex organics, and arising from a variety of environments from cold and diffuse to hot and dense gas. We present an LTE model to the spectral signatures of each molecule, constraining the source sizes for hot core species with complementary SMA interferometric observations, and assuming that molecules with related functional group composition are cospatial. For each molecule, a single model is given to fit all of the emission and absorption features of that species across the entire 480-1910 GHz spectral range, accounting for multiple temperature and velocity components when needed to describe the spectrum. As with other HIFI surveys toward massive star forming regions, methanol is found to contribute more integrated line intensity to the spectrum than any other species. We discuss the molecular abundances derived for the hot core, where the local thermodynamic equilibrium approximation is generally found to describe the spectrum well, in comparison to abundances derived for the same molecules in the Orion KL region from a similar HIFI survey.Comment: Accepted to ApJ. 64 pages, 14 figures. Truncated abstrac

Structure and Function of a Dual Reductase–Dehydratase Enzyme System Involved in p-Terphenyl Biosynthesis

We report the identification of the ter gene cluster responsible for the formation of the p-terphenyl derivatives terfestatins B and C and echoside B from the Appalachian Streptomyces strain RM-5-8. We characterize the function of TerB/C, catalysts that work together as a dual enzyme system in the biosynthesis of natural terphenyls. TerB acts as a reductase and TerC as a dehydratase to enable the conversion of polyporic acid to a terphenyl triol intermediate. X-ray crystallography of the apo and substrate-bound forms for both enzymes provides additional mechanistic insights. Validation of the TerC structural model via mutagenesis highlights a critical role of arginine 143 and aspartate 173 in catalysis. Cumulatively, this work highlights a set of enzymes acting in harmony to control and direct reactive intermediates and advances fundamental understanding of the previously unresolved early steps in terphenyl biosynthesis