Factors to keep in mind when introducing virtual microscopy

Digitization of glass slides and delivery of so-called virtual slides (VS) emulating a real microscope over the Internet have become reality due to recent improvements in technology. We have implemented a virtual microscope for instruction of medical students and for continuing medical education. Up to 30,000 images per slide are captured using a microscope with an automated stage. The images are post-processed and then served by a plain hypertext transfer protocol (http)-server. A virtual slide client (vMic) based on Macromedia's Flash MX, a highly accepted technology available on every modern Web browser, has been developed. All necessary virtual slide parameters are stored in an XML file together with the image. Evaluation of the courses by questionnaire indicated that most students and many but not all pathologists regard virtual slides as an adequate replacement for traditional slides. All our virtual slides are publicly accessible over the World Wide Web (WWW) at http://vmic.unibas.ch . Recently, several commercially available virtual slide acquisition systems (VSAS) have been developed that use various technologies to acquire and distribute virtual slides. These systems differ in speed, image quality, compatibility, viewer functionalities and price. This paper gives an overview of the factors to keep in mind when introducing virtual microscop

Cyclic stretch increases splicing noise rate in cultured human fibroblasts

BACKGROUND: Mechanical forces are known to alter the expression of genes, but it has so far not been reported whether they may influence the fidelity of nucleus-based processes. One experimental approach permitting to address this question is the application of cyclic stretch to cultured human fibroblasts. As a marker for the precision of nucleus-based processes, the number of errors that occur during co-transcriptional splicing can then be measured. This so-called splicing noise is found at low frequency in pre-mRNA splicing. FINDINGS: The amount of splicing noise was measured by RT-qPCR of seven exon skips from the test genes AATF, MAP3K11, NF1, PCGF2, POLR2A and RABAC1. In cells treated by altered uniaxial cyclic stretching for 18 h, a uniform and significant increase of splicing noise was found for all detectable exon skips. CONCLUSION: Our data demonstrate that application of cyclic stretch to cultured fibroblasts correlates with a reduced transcriptional fidelity caused by increasing splicing noise

The influence of SO2 fuming on the vegetation surrounding the Kahe power plant on Oahu, Hawaii

Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.The study relates to an investigation of the vegetation around Kahe power station, a recently established electricity generating plant at Kahe Point on SW Oahu. A vegetation map was prepared from aerial photographs at 1:5,000 and a search was made for possible S02 damage manifestations from the fumes emitted by the plant. Three major communities were identified, (1) closed forest of Prosopis pallida, (2) open forest-scrub dominated by Leucaena leucocephala and Acacia farnesiana and 3) open scrub-grassland dominated by the native pili grass (Heteropogon contortus). Within each of these major units, two to three floristic and structural subunits were mapped. No S02 damage was noted in the vascular plants. A separate survey of rock-lichens on identically sea-breeze-exposed ridges, north and south of the power plant, showed a considerably lower abundance of foliose rock-lichens in the southern area which receives much of the S02 plume. It was concluded that a beginning influence is shown by the lower abundance of lichens and that S02 damage in the vascular plants may show up only during the rainy season when the vegetation is actively growing. The investigation was done during the dry season in September.The following investigation was done as part of an integrated environmental impact study. The request for this investigation was directed to the ISLAND ECOSYSTEMS program of IBP as a service job. For this reason it is presented here as a technical report

The influence of feral goats on koa (Acacia koa Gray) reproduction in Hawaii Volcanoes National Park

Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.Goats were introduced to the Hawaiian Islands nearly 200 years ago. They have become wild and today roam in many Hawaiian ecosystems with dry-season climates from the lowlands to the mountains. A quantitative analysis was made to evaluate the influence of feral goats on tree reproduction of Acacia koa, in the mountain parkland ecosystem on the east flank of Mauna Loa. In this ecosystem, the endemic koa is the only important tree species. Here it reproduces vegetatively from root suckers. Suckering has resulted in the formation of small, dense tree colonies. Ten transects were established through a goat exclosure that was constructed three years earlier (in 1968). In addition, six transects were run across several typical nonfenced koa colonies. All suckers were counted, measured for height and mapped. It was shown that koa reproduction below 10 cm height is abundant outside the exclosure and at the unfenced colonies. Almost totally missing are suckers between 0.5 m and 2 m height. However, hundreds of this height grow inside the goat exclosure. Most of the few trees of this height found outside the fenced area were dying or dead showing that the current goat pressure is so high that the reproduction cycle of koa is nearly disrupted. The dense and vigorous sucker growth inside the exclosure, which is the result of current release from goat browsing pressure, was found to be an artifact. The artifact has resulted from increased suckering density caused by goat feeding and probably trampling on shallow roots. Thus, the entire forest stand structure in the mountain parkland is directly related to herbivore feeding and departs definitely in spacing and probably in height growth from the original forest structure as evolved during island ecosystem evolution

Succession patterns after pig digging in grassland communities of Mauna Loa, Hawaii

The influence of feral pigs on the composition of grassland communities on the east flank of Mauna Loa, Hawaii, was studied for the one year period from July, 1971, to August, 1972. Actual pig-disturbed areas as well as artificially scalped plots were included in the study. The succession on those plots was measured by both frequency and cover measurements. It was found that pig digging greatly enlarges the component of introduced species in communities with a former high percentage of native species.We wish to thank Rick Warshauer, Jim Jacobi and Grant Tanabe for their great help during field work and data processing

The influence of feral goats on the lowland vegetation in Hawaii Volcanoes National Park

Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.The coastal lowland of Hawaii Volcanoes National Park, particularly its western part, is a concentration center of feral goats. Here, in a tropical seasonal climate, a widespread vegetation is an annual Eragrostis tenella grassland that occurs on lava rock substrates with thin layers of ash. Localized within this area occurs also a small area of deep-ash deposit (Puu Kaone) that is occupied by perennial introduced grass with scrub. Experimental goat displacement in form of exclosures on these two grasslands has shown that both are entirely goat-derived vegetations. The response to displacement of goats was immediate in both areas. In the annual grassland, bunchgrasses, woody gamaephytes and an endemic legume vine (Canavalia kauensis) became established within less than two years, while the annuals are fast disappearing. In the perennial grassland, Melinis minutiflora enlarged its grass mat, woody plants became more abundant and exposed soil was partially covered within a year after exclosure construction. The remarkable recovery of the endemic vine in the annual grassland shows that goat removal still holds hopes for at least a partial return of native vegetation. The effects of goats apart of their physical degradation of the lowland ecosystem has been primarily in the form of exhausting the seed supply of native plants by feeding on seedlings wherever they occurred in this territory. Total elimination of goats from this area can be expected to yield a partial return of native plants on these rockland surfaces

Controlled mineralization and assembly of hydrolysis-based nanoparticles in organic solvents combining polymer micelles and microwave techniques

Controlled formation of nanoparticles in inverse diblock copolymer micelles by hydrolysis of titanium alkoxide precursors is described. Coagulation of the resulting TiO2-loaded micelles occurs on casting if the sample is prepared by conventional heating, allowing strings of TiO2 particles to form (see Figure). It is demonstrated that this can be prevented by microwave heating

Determination of the changes in contact area during osmotic stimulation of adhered primary hepatocytes.

<p>a) The dark patterns in the RICM image of two different wavelengths (470 nm shown here) correspond to cell patches with close surface contact. The original relative contact area (i) changes considerably during hypoosmotic stimulation (ii) and does not return to its original area afterwards (iii). A rapid decrease in relative contact area can be observed after returning to normoosmotic media (iv) followed by the stabilization of the relative contact area (v). b) All areas defined as relative contact areas in the consensus of both wavelengths are represented here as black areas. Images taken at 1 fps in both wavelength simultaneously enable a kinetic analysis: c) The tremendously quick reaction of the hepatocytes to the osmotic stimuli is evident as well as the stable plateaus (compared to the initial relative contact area (i)). The first plateau of this sample (iii) increases by ∼50% and the second (v) by ∼14%). Scale bars correspond to 10 µm.</p