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An accurate description of brain white matter anatomy in vivo remains a challenge. However, technical progress allows us to analyze structural variations in an increasingly sophisticated way. Current methods of processing diffusion MRI data now make it possible to correct some limiting biases. In addition, the development of statistical learning algorithms offers the opportunity to analyze the data from a new perspective. We applied newly developed tractography models to extract quantitative white matter parameters in a group of patients with chronic temporal lobe epilepsy. Furthermore, we implemented a statistical learning workflow optimized for the MRI diffusion data - the TractLearn pipeline - to model inter-individual variability and predict structural changes in patients. Finally, we interpreted white matter abnormalities in the context of several other parameters reflecting clinical status, as well as neuronal and cognitive functioning for these patients. Overall, we show the relevance of such a diffusion data processing pipeline for the evaluation of clinical populations. The "global to fine scale" funnel statistical approach proposed in this study also contributes to the understanding of neuroplasticity mechanisms involved in refractory epilepsy, thus enriching previous findings.

Ciliary neurotrophic factor (CNTF) participates in retinal development by inhibiting rod differentiation and promoting bipolar and Müller cell differentiation. In order to identify genes which are regulated by CNTF in the developing retina, we carried out a subtractive hybridization study. By this approach, we identified the Pleiotrophin (Ptn) as an upregulated gene in postnatal day 0 (P0) retinal explants upon addition of CNTF. Correlation of overall expression patterns between different retinal cell markers and Ptn in situ hybridization suggest that Ptn transcripts are initially expressed in progenitor cells then in postmitotic precursors of the INL expressing the Chx10 gene, and later in some differentiated retinal Müller glial (RMG) cells and rod–bipolar cells. Overexpression of Ptn by in vitro electroporation of P0 rat retinal explants partially blocks rod differentiation and promotes bipolar cell production, similar to effects of exogenous CNTF and leukemia inhibitory factor (LIF). Furthermore, in P0 retinal explants from mice lacking Ptn, the inhibitory effect of CNTF and LIF on rod differentiation is partially reduced and the cytokine-induced bipolar cell differentiation is largely prevented. Together, these results demonstrate that influence of CNTF family of cytokines on the differentiation of late retinal progenitor cell population is partially mediated by the release of Ptn.

Recent progress in lattice dynamics, based on the path integral formulation of statistical mechanics, is reviewed from a historical perspective. The improved effective potential theory is described and a detailed application to solid Ne is presented. The work is based on a nearest neighbor Mie-Lennard-Jones potential and contact is made with earlier theories based on the same potential.

Recent fundamental advances in formulating a reliable all-temperature lattice dynamics contain an uncontrolled approximation — the low-coupling approximation — routinely used in implementing the effective-potential Monte Carlo theory. We find that this approximation is most reliable when used in conjunction with the improved effective-potential Monte Carlo theory.

Using the anharmonic perturbation theory developed by Maradudin and Fein [Phys. Rev. 128 (1962) 2589] we investigate the reliability of the application of the frequency moments method to the calculation of the spectral shape of a one-dimensional Lennard-Jones crystal in both the classical and quantum regime.

To compare the consequences of water hardness on canning of dry beans, baked beans were prepared using water that contained 70 or 260 ppm calcium for soaking/blanching of navy beans and in the preparation of a tomato sauce for brine. Another factor examined for this project involved increasing the initial temperature of the canned beans prior to thermal processing by eliminating the cooling step after blanching. In general, if the initial temperature prior to thermal processing can be increased, the process time (Bb) is generally decreased. However, when the initial temperature of these baked beans was increased by this method, the process time increased in comparison to the time for beans that were cooled after blanching. In examining the water hardness, the beans, which had been cooled after blanching, processed with an increased CaCO3 demonstrated a decreased process time (Fo = 5.3) in comparison to those beans processed with a lower CaCO3. In one instance, the process time was decreased by 12% due to the presence of calcium possibly due to decreased gelatinization, physical restriction of swelling, reduced solubility of pectin, starch, and protein in the brine solution; consequently, these actions would increase the heat transfer in the food during thermal processing. Based on these investigations, water hardness should be considered an important parameter when performing heat-processing determinations and in the transference of heating data from one site to another.

Kidney and navy beans were given different soaking/blanching treatments and canned in 300 × 407 and 603 × 700 cans with each container receiving equal amounts of dry weight of that bean. The process time (Bb) for kidney beans decreased as the amount of moisture in the beans increased. For both kidney and navy beans soaked for 2 h, the process time decreased when the fill weight was increased by 12 and 8%, respectively. For 0 and 2 h soaked kidney beans, the drained weights after processing were statistically the same even though the kidney beans soaked for 2 h had a moisture level 3.3-fold greater. Comparing 2 h soaked beans with fully soaked, blanched beans, the process time increased significantly for fully soaked, blanched beans by 9 and 46% for beans in 300 × 407 can and 603 × 700 can, respectively. The operation of blanching tended to lower the process time and drained weight of navy beans.

A new procedure for microelectrophoretic delivery of horseradish peroxidase (HRP) is described. A dilute solution (1.5–3% w/v) of fluorescein isothiocyanate-conjugated HRP is deposited according to a standard microelectrophoretic method and the tissue reacted according to a sensitive histochemical procedure. A major advantage of this method is the reduced secondary diffusion of the enzyme present at the injection site.

Afferents to the interpeduncular nucleus (IPN) of the rat were studied with the horseradish peroxidase (HRP) retrograde transport method. HRP was deposited microelectrophoretically in the IPN of adult rats. Major projections to the IPN originate in the medial habenular nucleus, the region surrounding the dorsal tegmental nucleus (accessory dorsal tegmental nucleus and the so-called dorsal tegmental nucleus pars lateralis), and the midbrain raphe (nucleus centralis superior and nucleus raphe dorsalis). Also, minor projections originate in the central gray and nucleus locus coeruleus. Our results indicate that the habenulointerpeduncular projection originates solely from the medial habenular nuclei and is topographically organized; medial regions of the medial habenular nuclei project to ventral portions of IPN and lateral regions project to the dorsal IPN.