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As the IAU heads towards its second century, many changes have simultaneously transformed Astronomy and the human condition world-wide. Amid the amazing recent discoveries of exoplanets, primeval galaxies, and gravitational radiation, the human condition on Earth has become blazingly interconnected, yet beset with ever-increasing problems of over-population, pollution, and never-ending wars. Fossil-fueled global climate change has begun to yield perilous consequences. And the displacement of people from war-torn nations has reached levels not seen since World War II.
In 2007, the Ontario Health Technology Advisory Committee (OHTAC) developed a decision framework to guide decision making around nondrug health technologies. In 2012, OHTAC commissioned a revision of this framework to enhance its usability and deepen its conceptual and theoretical foundations.
The committee overseeing this work used several methods: (a) a priori consensus on guiding principles, (b) a scoping review of decision attributes and processes used globally in health technology assessment (HTA), (c) presentations by methods experts and members of review committees, and (d) committee deliberations over a period of 3 years.
The committee adopted a multi-criteria decision-making approach, but rejected the formal use of multi-criteria decision analysis. Three broad categories of attributes were identified: (I) context criteria attributes included factors such as stakeholders, adoption pressures from neighboring jurisdictions, and potential conflicts of interest; (II) primary appraisal criteria attributes included (i) benefits and harms, (ii) economics, and (iii) patient-centered care; (III) feasibility criteria attributes included budget impact and organizational feasibility.
The revised Ontario Decision Framework is similar in some respects to frameworks used in HTA worldwide. Its distinctive characteristics are that: it is based on an explicit set of social values; HTA paradigms (evidence based medicine, economics, and bioethics/social science) are used to aggregate decision attributes; and that it is rooted in a theoretical framework of optimal decision making, rather than one related to broad social goals, such as health or welfare maximization.
Peer review is central to political science. In this article we collect the ideas of journal editors in political science and several recent PhDs, who met as a panel at the 2011 American Political Science Association Annual Meeting to discuss the principles of the review process. This includes why reviewing is important to the development of one's own scholarship but also offers some nuts and bolts on reviewing.
Relationships between the X-ray and radio behavior of black hole X-ray binaries during outbursts have established a fundamental coupling between the accretion disks and radio jets in these systems. I begin by reviewing the prevailing paradigm for this disk-jet coupling, also highlighting what we know about similarities and differences with neutron star and white dwarf binaries. Until recently, this paradigm had not been directly tested with dedicated high-angular resolution radio imaging over entire outbursts. Moreover, such high-resolution monitoring campaigns had not previously targetted outbursts in which the compact object was either a neutron star or a white dwarf. To address this issue, we have embarked on the Jet Acceleration and Collimation Probe Of Transient X-Ray Binaries (JACPOT XRB) project, which aims to use high angular resolution observations to compare disk-jet coupling across the stellar mass scale, with the goal of probing the importance of the depth of the gravitational potential well, the stellar surface and the stellar magnetic field, on jet formation. Our team has recently concluded its first monitoring series, including (E)VLA, VLBA, X-ray, optical, and near-infrared observations of entire outbursts of the black hole candidate H 1743-322, the neutron star system Aquila X-1, and the white dwarf system SS Cyg. Here I present preliminary results from this work, largely confirming the current paradigm, but highlighting some intriguing new behavior, and suggesting a possible difference in the jet formation process between neutron star and black hole systems.
Previous studies of schizophrenia have suggested a linkage between neuropsychological (NP) deficits and hippocampus abnormality. The relationship between hippocampus volume and NP functioning was investigated in 24 patients with chronic schizophrenia and 24 matched healthy controls. Overall intracranial, white and gray matter, and anterior (AH) and posterior (PH) hippocampus volumes were assessed from magnetic resonance images (MRI). NP domains of IQ, attention, and executive function were also evaluated with respect to volumetric measures. It was hypothesized that AH and PH volumes and episodic memory scores would be positively associated in controls and that the schizophrenia group would depart from this normative pattern. NP functioning was impaired overall and AH volume was smaller in the schizophrenia group. In the controls, the hippocampus–memory relationships involved AH and PH, and correlations were significant for verbal memory measures. In the schizophrenia group, positive correlations were constrained to PH. Negative correlations emerged between AH and verbal and visual memory measures. For both groups, cortical volume negatively correlated with age, but a negative correlation between age and hippocampus volume was found only in the schizophrenia group. In this sample of adults with schizophrenia, atypical relationships between regional hippocampus volumes and episodic memory ability were found, as was an atypical negative association between hippocampus volume and age. (JINS, 2009, 15, 182–195.)
The present study uses cell-attached patch-recording
techniques to study the single-channel properties of Ca2+
channels in isolated salamander photoreceptors and investigate
their sensitivity to reductions in intracellular Cl−.
The results show that photoreceptor Ca2+ channels
possess properties similar to L-type Ca2+ channels
in other preparations, including (1) enhancement of openings
by the dihydropyridine agonist, (−)BayK8644; (2)
suppression by a dihydropyridine antagonist, nisoldipine;
(3) single-channel conductance of 22 pS with 82 mM Ba2+
as the charge carrier; (4) mean open probability of 0.1;
(5) open-time distribution fit with a single exponential
(τ0 = 1.1 ms) consistent with a single open
state; and (6) closed time distribution fit with two exponentials
(τc1 = 0.7 ms, τc2 = 25.4
ms) consistent with at least two closed states. Using a
Cl−-sensitive dye to measure intracellular
[Cl−], it was found that perfusion
with gluconate-containing, low Cl− medium
depleted intracellular [Cl−].
It was therefore possible to reduce intracellular
[Cl−] by perfusion with a low
Cl− solution while maintaining the extracellular
channel surface in high Cl− pipette
solution. Under these conditions, the single-channel
conductance was unchanged, but the mean open probability
fell to 0.03. This reduction can account for the 66% reduction
in whole-cell Ca2+ currents produced by perfusion
with low Cl− solutions. Examination of
the open and closed time distributions suggests that the
reduction in open probability arises from increases in
closed-state dwell times. Changes in intracellular
[Cl−] may thus modulate
photoreceptor Ca2+ channels.
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