[Picosecond infrared laser fiber-assisted sclerostomy (PIRL-FAST) : A first proof of principle analysis]. / Pikosekundenlaser-Faser-assistierte Sklerostomie (PIRL-FAST) : Ein erster Machbarkeitsnachweis.

INTRODUCTION: The aim of this study was an analysis of the feasibility of a picosecond infrared laser fiber-assisted sclerostomy (PIRL-FAST) using a novel sapphire fiber and different energy levels of the picosecond laser. METHOD: The laser-assisted sclerostomy was carried out with a newly generated sapphire fiber of the PIRL-HP2-1064 OPA-3000 (Attodyne, Canada). Immediately after the intervention, the eyes were fixed in phosphate-buffered 3.5% formaldehyde. For subsequent histological analysis the eyes were cut into 4 µm thick sections and stained with hematoxylin and eosin (H&E, Merck, Darmstadt, Germany). All preparations were then scanned and digitalized using the MIRAX SCAN (Carl Zeiss Microimaging GmbH, Jena, Germany). RESULTS: The pulse energies 150 µJ (N = 4), 175 µJ (N = 6), 200 µJ (N = 7) and 250 µJ (N = 6) were selected. Within the framework of this first feasibility analysis 400 µm (10 sequential sections) of the sclerotomies were evaluated. The mean area of PIRL-FAST showed a dependency on the pulse energy applied. The diameter of the collateral damage zone (CDZ) depended on the pulse energy used. The largest CDZ could be measured using the highest pulse energy in this experiment (250 µJ). The environmental scanning electron microscope (ESEM) results revealed circular smooth sclerostomy wall with only minimal change of tissue ultrastructure. CONCLUSION: The PIRL-FAST using sapphire fibers is a new minimally invasive instrument to provide robust stenting from the anterior chamber to the subconjunctival space. Since the PIRL has proven to work efficiently in sectioning several tissues with minimal collateral damage these first proof of principle experiments might pave the way for a new minimally invasive glaucoma surgery strategy. We have already initiated experiments to analyze the wound healing and scar formation in vivo.

Towards instantaneous cellular level bio diagnosis: laser extraction and imaging of biological entities with conserved integrity and activity.

The prospect for spatial imaging with mass spectroscopy at the level of the cell requires new means of cell extraction to conserve molecular structure. To this aim, we demonstrate a new laser extraction process capable of extracting intact biological entities with conserved biological function. The method is based on the recently developed picosecond infrared laser (PIRL), designed specifically to provide matrix-free extraction by selectively exciting the water vibrational modes under the condition of ultrafast desorption by impulsive vibrational excitation (DIVE). The basic concept is to extract the constituent protein structures on the fastest impulsive limit for ablation to avoid excessive thermal heating of the proteins and to use strongly resonant 1-photon conditions to avoid multiphoton ionization and degradation of the sample integrity. With various microscope imaging and biochemical analysis methods, nanoscale single protein molecules, viruses, and cells in the ablation plume are found to be morphologically and functionally identical with their corresponding controls. This method provides a new means to resolve chemical activity within cells and is amenable to subcellular imaging with near-field approaches. The most important finding is the conserved nature of the extracted biological material within the laser ablation plume, which is fully consistent with in vivo structures and characteristics.

Comparison of feed energy costs of maintenance, lean deposition, and fat deposition in three lines of mice selected for heat loss.

Three replications of mouse selection populations for high heat loss (MH), low heat loss (ML), and a nonselected control (MC) were used to estimate the feed energy costs of maintenance and gain and to test whether selection had changed these costs. At 21 and 49 d of age, mice were weighed and subjected to dual x-ray densitometry measurement for prediction of body composition. At 21 d, mice were randomly assigned to an ad libitum, an 80% of ad libitum, or a 60% of ad libitum feeding group for 28-d collection of individual feed intake. Data were analyzed using 3 approaches. The first approach was an attempt to partition energy intake between costs for maintenance, fat deposition, and lean deposition for each replicate, sex, and line by multiple regression of feed intake on the sum of daily metabolic weight (kg(0.75)), fat gain, and lean gain. Approach II was a less restrictive attempt to partition energy intake between costs for maintenance and total gain for each replicate, sex, and line by multiple regression of feed intake on the sum of daily metabolic weight and total gain. Approach III used multiple regression on the entire data set with pooled regressions on fat and lean gains, and subclass regressions for maintenance. Contrasts were conducted to test the effect of selection (MH - ML) and asymmetry of selection [(MH + ML)/2 - MC] for the various energy costs. In approach I, there were no differences between lines for costs of maintenance, fat deposition, or protein deposition, but we question our ability to estimate these accurately. In approach II, selection changed both cost of maintenance (P = 0.03) and gain (P = 0.05); MH mice had greater per unit costs than ML mice for both. Asymmetry of the selection response was found in approach II for the cost of maintenance (P = 0.06). In approach III, the effect of selection (P < 0.01) contributed to differences in the maintenance cost, but asymmetry of selection (P > 0.17) was not evident. Sex effects were found for the cost of fat deposition (P = 0.02) in approach I and the cost of gain (P = 0.001) in approach II; females had a greater cost per unit than males. When costs per unit of fat and per unit of lean gain were assumed to be the same for both sexes (approach III), females had a somewhat greater estimate for maintenance cost (P = 0.10). We conclude that selection for heat loss has changed the costs for maintenance per unit size but probably not the costs for gain.

Shear - wave velocities and soil period of unconsolidated sediments (soils) that underlie Evansville, Indiana

The unconsolidated sedimets (soils) underlying evanville, Indiana, are an important element contributing to the cities seismic risk. Knowledge of the shear - wave velocity of the unconsolidated sediment column is essential in predicting soil period, amplification potential, liquefaction risk, and other site responses to seismic shaking (AU)

Evidence of strong earthquake shaking in the lower wabash valley from prehistoric liquefaction features.

Earthquake-induced liquefaction features in Holocene sediments provide evidence of strong prehistoric shaking, magnitude m(b) 6.2 to 6.7, in the Wabash Valley bordering Indiana and Illinois. The source of the one or more earthquakes responsible was almost certainly in or near the Wabash Valley. The largest event is interpreted to have occurred between 7500 and 1500 years ago on the basis of archeological, pedological, and stratigraphic relations.

Perceptions of mental handicap: a comparison of Australian and Irish school children.

Australian secondary school children (N = 955) were surveyed concerning their perceptions of persons with mental handicap. Data collected related to reactions to meeting a person with disability, helping the handicapped person, responses to specific statements about handicapping conditions, causes of disability and the need for further information about handicaps. Results showed some parallels between Australian and Irish school children with both groups reflecting the positive impact.

Surgical management of carotid body tumor.

Carotid body tumor or chemodectoma is a slow-growing lesion; it should be diagnosed early to facilitate the technical surgical resection. When these lesions are large, the routine use of a carotid internal bypass shunt is advocated for their safe removal. With the newer vascular approaches, specifically the carotid internal bypass shunt, resection can be performed with acceptable risks. A patient with large bilateral carotid body tumors had successful resection of both these lesions.

[Susceptibility of leaves and fruits of tomato varieties and of their hybrids to attack by Phytophthora infestans]. / Die Prüfung von Tomatensorten und ihren Hybriden auf Blatt- und Fruchtbefall mit Phytophthora infestans.

1. The investigations were started to establish a correlation between the incidence of Phytophthora infestans (Mont.) de Bary on leaves and on fruits of tomatoes, the mechanism of the inheritance of the resistance and the number of responsible genes. 2. A close correlation was found between the spontaneous incidence on leaves and fruits and the results of artificial inoculation by the leaf-disc-test. The resistant types especially showed a remarkably low percentage of attack in all three tests. Resistant plants were successfully selected by means of the leaf-disc-test; the leaves as well as the fruits of the progeny were largely free from the disease. 3. The field-resistance of the variety 'Atom' was demonstrated to be due to a high degree of relative resistance of the leaves against the races T0 and T1. 4. The results obtained from F1-hybrids of 'Atom' with various more or less susceptible varieties indicate the participation of incompletely dominant genes. Since in the F2 a certain number of plants with a high degree of field-resistance could be selected, it is suggested that the field-resistance against Phytophthora infestans is based on a few genes only. From our results we conclude that principally two genes in the variety 'Atom' determine the field-resistance against the fungus. A participation of other modifier-genes can be supposed. We propose the gene-symbols Phf and Phf-2 for the Phytophthora-field-resistance.