14,602 research outputs found
Patient delays in seeking help at the onset of rheumatoid arthritis: the problem, its causes and potential solutions
Rheumatoid arthritis (RA) is a chronic inflammatory disease for which early treatment is vital to limit long term joint damage. However, people often delay in seeking medical help at the onset of RA symptoms. The early interpretation of symptoms and the process of making sense of symptoms impacts on both help-seeking decision-making and self-management. Furthermore, the general public’s perceptions and knowledge of RA may also affect the way that symptoms are interpreted. Examining the psychology behind early symptom interpretation, the barriers to help-seeking behaviour and investigating the public understandings of RA, can help us understand how decisions are made and guide us in developing interventions which encourage people to seek help promptly at the onset of RA
Optically controlled GaAs dual-gate MESFET and permeable base transistors
Optically induced voltage and dc characteristics of the GaAs Dual-gate MESFET and the Permeable Base Transistor (PBT) with optical illumination at wavelength below 0.87 microns were obtained and compared with GaAs MESFET. It was observed that PBT can handle higher current density when illuminated
CDC42 and Rac1 control different actin-dependent processes in the Drosophila wing disc epithelium.
Cdc42 and Rac1 are members of the rho family of small guanosinetriphosphatases and are required for a diverse set of cytoskeleton-membrane interactions in different cell types. Here we show that these two proteins contribute differently to the organization of epithelial cells in the Drosophila wing imaginal disc. Drac1 is required to assemble actin at adherens junctions. Failure of adherens junction actin assembly in Drac1 dominant-negative mutants is associated with increased cell death. Dcdc42, on the other hand, is required for processes that involve polarized cell shape changes during both pupal and larval development. In the third larval instar, Dcdc42 is required for apico-basal epithelial elongation. Whereas normal wing disc epithelial cells increase in height more than twofold during the third instar, cells that express a dominant-negative version of Dcdc42 remain short and are abnormally shaped. Dcdc42 localizes to both apical and basal regions of the cell during these events, and mediates elongation, at least in part, by effecting a reorganization of the basal actin cytoskeleton. These observations suggest that a common cdc42-based mechanism may govern polarized cell shape changes in a wide variety of cell types
The development of radiation resistant insulating layers for planar silicon technology, 29 May 1968 - 28 June 1969
Ion implantation method for improving radiation resistance of thermal oxides on silico
A study of charge storage in silicon oxide resulting from non-penetrating electron irradiation
Charge storage in silicon dioxide resulting from electron irradiatio
An extensible architecture for run-time monitoring of conversational web services
Trust in Web services will be greatly enhanced if these are subject to run-time verification, even if they were previously tested, since their context of execution is subject to continuous change; and services may also be upgraded without notifying their consumers in advance. Conversational Web services introduce added complexity when it comes to run-time verification, since they follow a conversation protocol and they have a state bound to the session of each consumer accessing them. Furthermore, conversational Web services have different policies on how they maintain their state. Access to states can be private or shared; and states may be transient or persistent. These differences must be taken into account when building a scalable architecture for run-time verification through monitoring. This paper, building on a previously proposed theoretical framework for run-time verification of conversational Web services, presents the design, implementation and validation of a novel run-time monitoring architecture for conversational services, which aims to provide a holistic monitoring framework enabling the integration of different verification tools. The architecture is validated by running a sequence of test scenarios, based on a realistic example. The experimental results revealed that the monitoring activities have a tolerable overhead on the operation of a Web service
Титульні сторінки
Influenza virus and vesicular stomatitis virus (VSV) obtain their lipid envelope by budding through the plasma membrane of infected cells. When monolayers of Madin-Darby canine kidney (MDCK) cells, a polarized epithelial cell line, are infected with fowl plague virus (FPV), an avian influenza virus, or with VSV, new FPV buds through the apical plasma membrane whereas VSV progeny is formed by budding through the basolateral plasma membrane. FPV and VSV were isolated from MDCK host cells prelabeled with [32P]orthophosphate and their phospholipid compositions were compared. Infection was carried out at 31 degrees C to delay cytopathic effects of the virus infection, which lead to depolarization of the cell surface. 32P-labeled FPV was isolated from the culture medium, whereas 32P-labeled VSV was released from below the cell monolayer by scraping the cells from the culture dish 8 h after infection. At this time little VSV was found in the culture medium, indicating that the cells were still polarized. The phospholipid composition of the two viruses was distinctly different. FPV was enriched in phosphatidylethanolamine and phosphatidylserine and VSV in phosphatidylcholine, sphingomyelin, and phosphatidylinositol. When MDCK cells were trypsinized after infection and replated, non-infected control cells attached to reform a confluent monolayer within 4 h, whereas infected cells remained in suspension. FPV and VSV could be isolated from the cells in suspension and under these conditions the phospholipid composition of the two viruses was very similar. We conclude that the two viruses obtain their lipids from the plasma membrane in the same way and that the different phospholipid compositions of the viruses from polarized cells reflect differences in the phospholipid composition of the two plasma membrane domains
Fluctuation and Commensurability Effect of Exciton Density Wave
At low temperatures, indirect excitons formed at the in-plane electron-hole
interface in a coupled quantum well structure undergo a spontaneous transition
into a spatially modulated state. We report on the control of the instability
wavelength, measurement of the dynamics of the exciton emission pattern, and
observation of the fluctuation and commensurability effect of the exciton
density wave. We found that fluctuations are strongly suppressed when the
instability wavelength is commensurate with defect separation along the exciton
density wave. The commensurability effect is also found in numerical
simulations within the model describing the exciton density wave in terms of an
instability due to stimulated processes
Dynamics of the BCS-BEC crossover in a degenerate Fermi gas
We study the short-time dynamics of a degenerate Fermi gas positioned near a
Feshbach resonance following an abrupt jump in the atomic interaction resulting
from a change of external magnetic field. We investigate the dynamics of the
condensate order parameter and pair wavefunction for a range of field
strengths. When the abrupt jump is sufficient to span the BCS to BEC crossover,
we show that the rigidity of the momentum distribution precludes any
atom-molecule oscillations in the entrance channel dominated resonances
observed in the 40K and 6Li. Focusing on material parameters tailored to the
40K Feshbach resonance system at 202.1 gauss, we comment on the integrity of
the fast sweet projection technique as a vehicle to explore the condensed phase
in the crossover regionComment: 5 pages, 4 figure
Detection of radio-frequency modulated optical signals by two and three terminal microwave devices
An interdigitated photoconductor (two terminal device) on GaAlAs/GaAs heterostructure was fabricated and tested by an electro-optical sampling technique. Further, the photoresponse of GaAlAs/GaAs HEMT (three terminal device) was obtained by illuminating the device with an optical signal modulated up to 8 GHz. Gain-bandwidth product, response time, and noise properties of photoconductor and HEMT devices were obtained. Monolithic integration of these photodetectors with GaAs microwave devices for optically controlled phased array antenna applications is discussed
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