Volatile compounds from the mite Acarus siro L. in food

The headspace above two strains of Acarus siro maintained on wheat germ/bran has been shown to contain the hydrocarbons, decane, undecane and tridecane together with the furanoid terpene, perillen. When the bodies of the separated mites were extracted with diethyl ether a new compound was found in addition to those in the headspace. This compound has been identified as 2-hydroxy-6-methyl benzaldehyde. None of these compounds appears to be responsible for the ‘minty’ smell reportedly related to mite infestation.     

Validity, predictive efficiency, and practical significance of selection tests.

The acceptance of validity coefficients at face value as measures of practical significance is evaluated by examining each functional relationship between 3 indexes of predictive efficiency r, r2, and E and 3 measures of practical significance the increase of the criterion mean, the expected proportion "satisfactory," and the expected proportion in 10 criterion categories. The validity coefficient, r is a linear function of the increase of the criterion mean and very nearly a linear function of the other 2 measures of practical significance; r2 and E are related to these 3 measures in a more curvilinear manner. A table is presented that gives the proportion expected in each of 18 criterion categories as a function of r and the selection ratio. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

First- and second-order information in natural images: a filter-based approach to image statistics

Previous analyses of natural image statistics have dealt mainly with their Fourier power spectra. Here we explore image statistics by examining responses to biologically motivated filters that are spatially localized and respond to first-order (luminance-defined) and second-order (contrast- or texture-defined) characteristics. We compare the distribution of natural image responses across filter parameters for first- and second-order information. We find that second-order information in natural scenes shows the same self-similarity previously described for first-order information but has substantially less orientational anisotropy. The magnitudes of the two kinds of information, as well as their mutual unsigned correlation, are much stronger for particular combinations of filter parameters in natural images but not in unstructured fractal images having the same power spectra.     

Tutorial on the biology of nanotopography

The aims of this short tutorial are fourfold: 1) to introduce readers unfamiliar with the field to major concepts in the field; 2) to inform the reader of major unresolved questions; 3) to inform readers of a few major sources of relevant literature; and 4) to place the subject in relation to its relevance to other areas of science and practical application.     

Fetal MEG redistribution by projection operators

The fetal magnetoencephalogram (fMEG) is measured in the presence of large interference from the maternal and fetal magnetocardiograms. This interference can be efficiently attenuated by orthogonal projection of the corresponding spatial vectors. However, the projection operators redistribute the fMEG signal among sensors. Although redistribution can be readily accounted for in the forward solution, visual interpretation of the fMEG signal topography is made difficult. We have devised a general, model-independent method for correction of the redistribution effect that utilizes the assumption that we know in which channels the fMEG should be negligible (such channels are distant from the known fetal head position). In a simplified case where the fMEG can be explained by equivalent current dipoles, the correction can also be obtained from fitting the dipoles to the fMEG signal. The corrected fMEG signal topography then corresponds to the dipole forward solution, but without orthogonal projection. We illustrate the redistribution correction on an example of experimentally measured flash evoked fMEG.     

Micro and nano-structured surfaces

The study of cell reaction to micro and nanotopography is dependent on the method of manufacture available. Several methods of manufacture have been developed: polymer demixing, embossing and photolithography. Surfaces obtained with these different techniques, having micro and/or nanodomains, have been studied toward the same type of cells, i.e. human endothelial cells (HGTFN) and mouse fibroblasts (3T3). Polymer demixing of polystyrene (PS) and poly(4-bromostyrene) (PBrS) producing nanometrically islands of 18, 45 and 100 nm height, polycarbonate (PC) and polycaprolactone (PCL) grooved with grooves 450 nm wide and 190 high, the natural polysaccharide hyaluronic acid (Hyal) and its sulfated derivative (HyalS) photoimmobilized on silanized glass as grooves 250 nm high and 100, 50, 25 or 10 m wide have been obtained. The morphology and polarization of the cells has been studied by optical microscopy and scanning electron microscopy. Cells respond in different way to the topography of the materials, but the surface chemistry is dominant in inducing different cell behavior.     

Temperature-dependent optical constants of water ice in the near infrared: new results and critical review of the available measurements

The optical constants of water ice have been determined in the near infrared from 4000 to 7000 cm(-1). Polycrystalline ice films with thickness as great as ~1164 mum were formed by condensation of water vapor on a cold silicon substrate at temperatures of 166, 176, 186, and 196 K. The transmission of light through the ice films was measured during their growth from 0 to 1164 mum over the frequency range of approximately 500-7000 cm(-1). The optical constants were extracted by means of simultaneously fitting the calculated transmission spectra of films of varying thickness to their respective measured transmission spectra with an iterative Kramers-Kronig technique. Equations are presented to account for reflection losses at the interfaces when the sample is held in a cell. These equations are used to reanalyze the transmission spectrum of water ice (358-mum sample at 247 K) recorded by Ockman in 1957 [Philos. Mag. Suppl. 7, 199 (1958)]. Our imaginary indices for water ice are compared with those of Gosse et al. [Appl. Opt. 34, 6582 (1995)], Kou et al. [Appl. Opt. 32, 3531 (1993)], Grundy and Schmitt [J. Geophys. Res. 103, 25809 (1998)], and Warren [Appl. Opt. 23, 1206 (1984)], and with the new indices from Ockman's spectrum. The temperature dependence in the imaginary index of refraction observed by us between 166 and 196 K and that between our data at 196 K and the data of Gosse et al. at 250 K are compared with that predicted by the model of Grundy and Schmitt. On the basis of this comparison a linear interpolation of the imaginary indices of refraction between 196 and 250 K is proposed. We believe that the accuracy of this interpolation is better than 20%.     

(Close) distance makes the heart grow fonder: Improving implicit racial attitudes and interracial interactions through approach behaviors.

In 4 studies, the authors examined the effect of approaching Blacks on implicit racial attitudes and immediacy behaviors. In Studies 1-3, participants were trained to pull a joystick toward themselves or to push it away from themselves when presented with photographs of Blacks, Whites, or Asians before completing an Implicit Association Test to measure racial bias. In Study 4, the effect of this training procedure on nonverbal behavior in an interracial contact situation was investigated. Results from the studies demonstrated that approaching Blacks decreased participants' implicit racial prejudice and increased immediacy when interacting with a Black confederate. The implications of these findings for current theories on approach, avoidance, and intergroup relations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)