Ability factors and cognitive processes

Several measures of the speed of information processing were related to ability factors derived from the Cattell-Horn theory of fluid and crystallized intelligence. Ninety-one college students took a battery of paper and pencil tests designed to measure four ability factors: fluid intelligence (Gf), crystallized intelligence (Gc), spatial visualization (Gv), and clerical perceptual speed (CPS). They also performed paper and pencil and computerized versions of three information processing tasks: mental rotations, letter matching, and sentence verification. Correlations among the ability measures, among the information processing measures, and between the two domains were analyzed using confirmatory factor analysis. The four ability factors were found to be largely independent in this college population. Speed of letter-matching and sentence verification were highly correlated, but neither was related to speed of mental rotation. Mental rotation speed was strongly correlated with Gv; letter matching speed was correlated with CPS; and sentence verification speed was correlated with both Gc and CPS.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23856/1/0000095.pd

Information processing correlates of reading

Individual differences in reading correlate with individual differences in perception, in memory, and in other simple processes. This study measured these relationships using information processing tasks such as visual search, visual matching, and span of apprehension; and using linguistic processing tasks such as word-nonword judgment, picture-sentence verification, and semantic categorization. These tasks were performed by a large sample of college students chosen to represent the full range of college-level reading ability. Three salient findings emerged: (a) Reading correlates with the information processing measures when they involve words, but it does not correlate with otherwise identical measures involving letters. (b) Reading speed and comprehension have different correlations with the information processing measures, although they have similar correlations with the linguistic processing measures. (c) Reading speed is only moderately correlated with listening comprehension, but reading comprehension ability is indistinguishable from listening comprehension ability. These results indicate that reading speed and comprehension depend on abilities that are at least partly distinct. Specifically, reading speed varies with visual word processing, while reading comprehension varies with nonvisual linguistic processing.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25758/1/0000319.pd

Observations of Infrared Radiative Cooling in the Thermosphere on Daily to Multiyear Timescales from the TIMED/SABER Instrument

We present observations of the infrared radiative cooling by carbon dioxide (CO2) and nitric oxide (NO) in Earth s thermosphere. These data have been taken over a period of 7 years by the SABER instrument on the NASA TIMED satellite and are the dominant radiative cooling mechanisms for the thermosphere. From the SABER observations we derive vertical profiles of radiative cooling rates (W/cu m), radiative fluxes (W/sq m), and radiated power (W). In the period from January 2002 through January 2009 we observe a large decrease in the cooling rates, fluxes, and power consistent with the declining phase of solar cycle. The power radiated by NO during 2008 when the Sun exhibited few sunspots was nearly one order of magnitude smaller than the peak power observed shortly after the mission began. Substantial short-term variability in the infrared emissions is also observed throughout the entire mission duration. Radiative cooling rates and radiative fluxes from NO exhibit fundamentally different latitude dependence than do those from CO2, with the NO fluxes and cooling rates being largest at high latitudes and polar regions. The cooling rates are shown to be derived relatively independent of the collisional and radiative processes that drive the departure from local thermodynamic equilibrium (LTE) in the CO2 15 m and the NO 5.3 m vibration-rotation bands. The observed NO and CO2 cooling rates have been compiled into a separate dataset and represent a climate data record that is available for use in assessments of radiative cooling in upper atmosphere general circulation models

Atomic oxygen in the mesosphere and lower thermosphere derived from SABER : Algorithm theoretical basis and measurement uncertainty

Peer reviewedPublisher PD

Writing in Britain and Ireland, c. 400 to c. 800

No abstract available

Novel Approaches to Inhibit HIV Entry

Human Immunodeficiency Virus (HIV) entry into target cells is a multi-step process involving binding of the viral glycoprotein, Env, to its receptor CD4 and a coreceptor—either CCR5 or CXCR4. Understanding the means by which HIV enters cells has led to the identification of genetic polymorphisms, such as the 32 base-pair deletion in the ccr5 gene (ccr5∆32) that confers resistance to infection in homozygous individuals, and has also resulted in the development of entry inhibitors—small molecule antagonists that block infection at the entry step. The recent demonstration of long-term control of HIV infection in a leukemic patient following a hematopoietic stem cell transplant using cells from a ccr5∆32 homozygous donor highlights the important role of the HIV entry in maintaining an established infection and has led to a number of attempts to treat HIV infection by genetically modifying the ccr5 gene. In this review, we describe the HIV entry process and provide an overview of the different classes of approved HIV entry inhibitors while highlighting novel genetic strategies aimed at blocking HIV infection at the level of entry