Association of ezrin with intercellular adhesion molecule-1 and -2 (ICAM-1 and ICAM-2). Regulation by phosphatidylinositol 4, 5-bisphosphate

Ezrin is a cytoplasmic linker molecule between plasma membrane components and the actin-containing cytoskeleton. We studied whether ezrin is associated with intercellular adhesion molecule (ICAM)-1, -2, and -3. In transfected cells, ICAM-1 and ICAM-2 colocalized with ezrin in microvillar projections, whereas an ICAM-1 construct attached to cell membrane via a glycophosphatidylinositol anchor was uniformly distributed on the cell surface. An interaction of ICAM-2 and ezrin was seen by affinity precipitation, microtiter binding assay, coimmunoprecipitation, and surface plasmon resonance methods. The calculated KD value was 3.3 x 10(-7) M. Phosphatidylinositol 4, 5-bisphosphate (PtdIns(4,5)P2) induced an interaction of ezrin and ICAM-1 and enhanced the interaction of ezrin and ICAM-2, but ICAM-3 did not bind ezrin even in the presence of PtdIns(4,5)P2. PtdIns(4, 5)P2 was shown to bind to cytoplasmic tails of ICAM-1 and ICAM-2, which are the first adhesion proteins demonstrated to interact with PtdIns(4,5)P2. The results indicate an interaction of ezrin with ICAM-1 and ICAM-2 and suggest a regulatory role of phosphoinositide signaling pathways in regulation of ICAM-ezrin interaction.     

Finnish PACS project.

A Finnish PACS project has been set up with the participation and financing of 13 university and central hospitals, the Medical Board of Finland, the Hospital League of Finland, the Post and Teleoffice of Finland and the Helsinki Telephone Company with the Medical Engineering Laboratory of the Technical Research Centre of Finland as the principal investigator. The project started in December 1988 and ended in December 1990. The project focused on the functional needs for PACS. The image production, archive sizes, network capacity and workstation requirements have been studied in a big university hospital. The results show that without compression the image archive size needs to be at least 10 TB. The network capacity requirement depends very much on the interactivity requirements. In normal situations less than 1 Mbit/s is needed, if the network is configured in an efficient way. In some cases, however, the speed requirement can be of the order of 100 Mbit/s. A proposal for a hospital-wide PACS network was made. Simple calculation rules to estimate the needed capacities were also developed.     

Performance evaluation of directive handset antenna inmicrocellular environment

The effect of a directive handset antenna on the performance of mobile radio systems has been studied by comparing the simulated relative received power of a directive antenna with the received power of an omnidirectional antenna in a microcellular environment at 1.8 GHz. Different radiation patterns have been used to find out the effect of pattern shape, nulls and the general level of the backlobe     

Effect of adjacent IS-95 network to WCDMA uplink capacity

The paper derives the degradation of wideband code-division multiple-access (WCDMA) uplink capacity in the situation where an IS-95 system is deployed at the adjacent frequency band. A system modeling approach that combines accurate path loss information with simplified and computationally fast interference modeling is also described. The model takes into account the power-control coupling between IS-95 and WCDMA systems as well as the effect of downlink blocking. The paper also includes some numerical examples from realistic micro- and macrocellular network scenarios. The results show that the interference is dependent on, in addition to the filter characteristics, the used network scenario, whether the interfered or interfering system is microcellular or macrocellular, and on the relative cell densities of the interfering and interfered networks. The developed method can be utilized for WCDMA network planning, for frequency allocation, and for system design of the mobile telecommunication systems.     

Backscattering properties of boreal forests at the C- and X-bands

The backscattering properties of boreal forests are studied using empirical airborne and spaceborne radar data from Finland. Airborne measurements were carried out in the summer of 1992 by the HUTSCAT scatterometer at the Teijo test area in southern Finland. The HUTSCAT scatterometer is an eight-channel helicopter-borne profiling radar operating at the C- and X-bands. The ranging capability of the HUTSCAT scatterometer was employed in the semiempirical modeling of forest backscatter. The backscatter profile information was used in the analysis of the canopy transmissivity and the canopy backscattering coefficient by distinguishing backscattering contributions from the canopy and the ground. Additionally, ERS-1 C-band satellite SAR measurements were obtained for the Teijo test area and for the reference test area in Sodankyla in northern Finland. The radar results were compared with operational ground-based forest assessment data on forest compartments (stands) of the area. The key parameter investigated was the stem (bole) volume per hectare. The results obtained show the behavior of the canopy transmissivity and the canopy backscatter as a function of stem volume (directly related to the forest biomass). The influence of seasonal and diurnal changes on, and the effects of the changes in soil moisture to the backscattering coefficient were also investigated     

Capacity reduction of WCDMA downlink in the presence ofinterference from adjacent narrow-band system

One of the main challenges when implementing the future mobile multimedia networks is the cost-effective network evolution from second- to third-generation systems. This evolution path may include the use of different technologies at the same frequency band. The performance of the wide-band code-division multiple-access (WCDMA) downlink is studied in the case when there are narrow-band (NB) interference sources at the adjacent frequencies. A simple, analytical method to calculate the downlink capacity reduction of the WCDMA macrocell in this case is presented. The analysis takes into account different downlink interference mechanisms: wide-band noise from the transmitter as well as adjacent channel interference, intermodulation, and cross-modulation originating in the mobile receiver. The effect of each interference component to the capacity of the WCDMA macrocellular network has been evaluated with numerical examples. The analysis shows that capacity per cell is sensitive to the cell size, and therefore very careful network planning is needed in order to operate the WCDMA networks efficiently. The results of this paper can be utilized when implementing the WCDMA system to the same band with existing narrow-band systems, for instance, with the PCS 1900 band in United States and GSM 1800 band in Europe     

The temporal,PFGE and resistance pattern associations suggest that poultry products are only a minor source of human infections in Western Finland

In order to compare human and retail poultry meat thermophilic Campylobacter isolates originating in a regional area in Western Finland, minimum inhibitory concentration (MICs) for six antimicrobials (96 isolates) and pulsed-field gel electrophoresis (PFGE) (102 isolates) were analysed. Campylobacter spp. were detected in 10.5% out of 305 fresh poultry products studied; 29 (90.5%) isolates were identified as Campylobacter jejuni. Among the 70 human isolates, 66 (94.3%) isolates were identified as C. jejuni. Only one C. jejuni domestic poultry isolate showed resistance (ampicillin), whereas domestic human C. jejuni isolates were more commonly resistant to ciprofloxacin, nalidixic acid, ampicillin and tetracycline. The resistance in foreign human isolates was significantly more common than among domestic isolates. PFGE analysis with KpnI restriction enzyme resulted in 59 different PFGE types among the poultry and human isolates. Three types were detected first in poultry meat and thereafter during the following month in domestic human samples, whereas the other conjoint types were detected only after many months. This study suggests that poultry products play only a minor role in human campylobacteriosis in the study area and that the resistance found in domestic human isolates is not likely related to retail poultry meat products.     

WCDMA Downlink Coverage Reduction Due to Adjacent Channel Interference

This paper determines the coverage reduction of the Wideband CDMA (WCDMA) downlink in the case of interference, due to adjacent narrowband system. The coverage reduction has been evaluated in terms of blocking area around the interfering base station. The analysis takes into account different interference mechanisms and their individual effects to the coverage. The interference mechanisms which have been considered here are the out-of-band emissions of the base station transmitter, the adjacent channel interference due to non-ideal sideband filtering, the intermodulation and the crossmodulation. The coverage effects in realistic network environment have been computed by using accurate ray-tracing propagation models designed for the path loss calculation in the urban environment. In the numerical examples, the effect of GSM interference has been demonstrated, but the method can be utilized with other narrowband systems as well. The results can be utilized in radio system design, radio network planning (RNP) and the frequency allocation of the WCDMA systems.     

Binomial array as a multistate phase diversity antenna

If two in-phase plane waves arrive at an antenna from different directions, the resulting signal is not necessarily the coherent sum of the two incoming signals. This is due to the fact that the antenna radiation pattern is actually a complex quantity containing amplitude and phase properties. Thus, it can be stated that antenna phase characteristics may vary as a function of direction. In free space, the antenna phase pattern does not have any role in radio communications in contrast to mobile communications in an urban microcell where the radio channel is very complicated due to multipath propagation. Array antennas offer possibilities to control its phase properties in transmission and reception, which offer a simple technique to improve the combination of received multipath signal components. Binomial arrays are one possibility to implement similar directive beams which, however, have different phase patterns compared to each other. A set of these beams could be used in a discretely optimizing receiver system much in the same way as other diversity techniques are used. A four-element array and results from a microcell radio channel environment simulation are presented as a demonstration of this technique