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1.
Multi-user facilities serve as a resource for many universities. In 2010, a survey was conducted investigating possible changes and successful characteristics of multi-user facilities, as well as identifying problems in facilities. Over 300 surveys were e-mailed to persons identified from university websites as being involved with multi-user facilities. Complete responses were received from 36 facilities with an average of 20 years of operation. Facilities were associated with specific departments (22%), colleges (22%), and university research centers (8.3%) or were not affiliated with any department or college within the university (47%). The five most important factors to succeed as a multi-user facility were: 1) maintaining an experienced, professional staff in an open atmosphere; 2) university-level support providing partial funding; 3) broad client base; 4) instrument training programs; and 5) an effective leader and engaged strategic advisory group. The most significant problems were: 1) inadequate university financial support and commitment; 2) problems recovering full service costs from university subsidies and user fees; 3) availability of funds to repair and upgrade equipment; 4) inability to retain highly qualified staff; and 5) unqualified users dirtying/damaging equipment. Further information related to these issues and to fee structure was solicited. Overall, there appeared to be a decline in university support for facilities and more emphasis on securing income by serving clients outside of the institution and by obtaining grants from entities outside of the university.  相似文献   
2.
Web-based telemicroscopy   总被引:2,自引:0,他引:2  
By taking advantage of network-based computing and the recent developments in Web interfaces, centralized research facilities housing specialized and unique imaging instruments along with associated high-performance computing can be made available to researchers for use from their own laboratories. In addition to increasing access and utilization of these facilities, operation over the Internet is expected to enhance research by facilitating collaboration between researchers. We describe the implementation of a platform-independent Web-based system written in Java that supplements automated functions with video-guided interactive, collaborative remote control and data acquisition from an intermediate-high-voltage electron microscope.  相似文献   
3.
The use of biofeedback devices has been plagued by the garbage in—garbage out problem since its inception. This paper reviews the basics of how to use biofeedback devices for surface electromyographic applications at each stage in the process from sensors to displays so meaningful information can be gathered and utilized.  相似文献   
4.
An instrumentation and automation system for a side-vented pan coater with a novel air-flow rate measurement system for monitoring the film-coating process of tablets was designed and tested. The instrumented coating system was tested and validated by film-coating over 20 pilot-scale batches of tablets with aqueous-based hydroxypropyl methylcellulose (HPMC). Thirteen different process parameters were continuously measured and monitored, and the most significant ones were logged for analysis. Laser profilometry was used to measure the surface roughness of the coated tablets. The instrumentation system provided comprehensive and quantitative information on the process parameters monitored. The measured process parameters and the responses of the film-coated tablet batches showed that the coating process is reproducible. The inlet air-flow rate influenced the coating process and the subsequent quality of the coated tablets. Increasing the inlet flow rate accelerated the drying of the tablet surface. At high inlet flow rate, obvious film-coating defects (ie, unacceptable surface roughness of the coated tablets) were observed and the loss of coating material increased. The instrumented and automated pancoating system described, including historical data storage capability and a novel air-flow measurement system, is a useful tool for controlling and characterizing the tablet film-coating process. Monitoring of critical process parameters increases the overall coating process efficiency and predictability.  相似文献   
5.
A review of computer control of fermentation processes is presented. Hardware and software technologies that have been used to implement computer control are discussed. This includes instrumentation, interfacing techniques, computer hardware configurations, data logging and documentation, displays and man-machine interaction, low-level control, back-up and error detection and programming techniques. Advanced control of fermentation processes with the utilization of modern control techniques is also presented. This topic is divided into steady state optimization and dynamic optimization. Finally, on-line estimation of bioreactor parameters for feedback control is presented.  相似文献   
6.
Diagnostic catheters based on fibre Bragg gratings (FBG's) are proving to be highly effective for measurement of the muscular activity associated with motility in the human gut. While the primary muscular contractions that generate peristalsis are circumferential in nature, it has long been known that there is also a component of longitudinal contractility present, acting in harmony with the circumferential component to improve the overall efficiency of material movement. We report the detection of longitudinal motion in mammalian intestine using an FBG technique that should be viable for similar detection in humans. The longitudinal sensors have been combined with our previously reported FBG pressure sensing elements to form a composite catheter that allows the relative phase between the two components to be detected. The catheter output has been validated using video mapping in an ex‐vivo rabbit ileum preparation. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
7.
The UAH Logging, Trace Recording, and Analysis instrumentation (ULTRA) provides highly repeatable (0.0002% variation) application instruction counts for parallel programs which are invariant to the communication network used, the number of processors used, and the MPI communication library used. ULTRA, implemented as an MPI profiling wrapper, avoids the data collection system artifacts of time-based measurements by using instruction counts as the basic measure of work performed and records the operation performed and the amount of data sent for each network operation. These measurements can be scaled appropriately for various target architectures. ULTRA's instrumentation overhead is minimized by using the Pentium II processors's performance monitoring hardware, allowing large, production-run applications to be quickly characterized. Traces of the NAS benchmarks representing 6.67×1012 application instructions were generated by ULTRA. The application instructions executed per byte injected into the network and the instructions executed per message sent were computed from the traces. These values can be scaled by the expected processor performance to estimate the minimum network performance required to support the programs. It is impossible to use time-based measurements for this purpose due to measurement artifacts caused by the background processes and the communication network of the data collection system.  相似文献   
8.
The European X-ray free-electron laser (XFEL) facility, under construction in the Hamburg region, will provide high-peak brilliance (greater than 1033 photons s−1 mm−2 mrad−2 per 0.1% BW), ultrashort pulses (approx. 10 fs) of X-rays, with a high repetition rate (up to 27 000 pulses s−1) from 2016 onwards. The main features of this exceptional X-ray source, and the instrumentation developments necessary to exploit them fully, for application to a variety of scientific disciplines, are briefly summarized. In the case of structural biology, that has a central role in the scientific case of this new facility, the instruments and ancillary laboratories that are being planned and built within the baseline programme of the European XFEL and by consortia of users are also discussed. It is expected that the unique features of the source and the advanced features of the instrumentation will allow operation modes with more efficient use of sample materials, faster acquisition times, and conditions better approaching feasibility of single molecule imaging.  相似文献   
9.
Imaging dynamic changes in chlorophyll a fluorescence provides a valuable means with which to examine localised changes in photosynthetic function. Microscope-based systems provide excellent spatial resolution which allows the response of individual cells to be measured. However, such systems have a restricted depth of focus and, as leaves are inherently uneven, only a small proportion of each image at any given focal plane is in focus. In this report we describe the development of algorithms, specifically adapted for imaging chlorophyll fluorescence and photosynthetic function in living plant cells, which allow extended-focus images to be reconstructed from images taken in different focal planes. We describe how these procedures can be used to reconstruct images of chlorophyll fluorescence and calculated photosynthetic parameters, as well as producing a map of leaf topology. The robustness of this procedure is demonstrated using leaves from a number of different plant species. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
10.
Light-emitting diodes as a light source for photosynthesis research   总被引:10,自引:0,他引:10  
Light-emitting diodes (LED) can provide large fluxes of red photons and so could be used to make lightweight, efficient lighting systems for photosynthetic research. We compared photosynthesis, stomatal conductance and isoprene emission (a sensitive indicator of ATP status) from leaves of kudzu (Pueraria lobata (Willd) Ohwi.) enclosed in a leaf chamber illuminated by LEDs versus by a xenon arc lamp. Stomatal conductance was measured to determine if red LED light could sufficiently open stomata. The LEDs produced an even field of red light (peak emission 656±5 nm) over the range of 0–1500 mol m-2 s-1. Under ambient CO2 the photosynthetic response to red light deviated slightly from the response measured in white light and stomatal conductance followed a similar pattern. Isoprene emission also increased with light similar to photosynthesis in white light and red light. The response of photosynthesis to CO2 was similar under the LED and xenon arc lamps at equal photosynthetic irradiance of 1000 mol m-2 s-1. There was no statistical difference between the white light and red light measurements in high CO2. Some leaves exhibited feedback inhibition of photosynthesis which was equally evident under irradiation of either lamp type. Photosynthesis research including electron transport, carbon metabolism and trace gas emission studies should benefit greatly from the increased reliability, repeatability and portability of a photosynthesis lamp based on light-emitting diodes.  相似文献   
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