Content-Centered Collaboration Spaces in the Cloud

Emphasizing communication, collaborative work, and community, the authors envision a cloud-based platform that inverts the traditional application-content relationship by placing content rather than applications at the center, enabling users to rapidly build customized solutions around their content items. The future of collaboration will focus on building and sustaining communities around content, tasks, and ideas. Hosted entities known as content spaces will support ecosystems of users and developers around this content. To make their case, the authors review the dominant trends in computing that motivate the exploration of new approaches for content-centered collaboration and discuss ways to address certain core problems for users and organizations.     

Comparison of steam and autothermal reforming of methanol using a packed-bed low-cost copper catalyst

Small-scale reformers for hydrogen production via steam and autothermal reforming of hydrocarbon feedstocks can be a solution to the lack of hydrogen distribution infrastructure. A packed-bed reactor is one possible design for such purpose. However, the two reforming processes of steam and autothermal methods have different characteristics, thus they have different and often opposite design requirements. In implementing control strategy for small-scale reformers, understanding the overall chemical reactions and the reactor physical properties becomes essential. This paper presents some inherent features of a packed-bed reactor that can both improve and/or degrade the performance of a packed-bed reactor with both reforming modes.The high thermal resistance of the packed bed is disadvantageous to steam reforming (SR), but it is beneficial to the autothermal reforming (ATR) mode with appropriate reactor geometry. The low catalyst utilization in steam reforming can help to prevent the unconverted fuel leaving the reactor during transient by allowing briefly for higher reactant fuel flow rates. In this study, experiments were performed using three reactor geometries to illustrate these properties and a discussion is presented on how to take advantages of these properties in reactor design.     

Interstitial implantation of gynecologic malignancies

Interstitial implantation is invaluable in the management of patients with extensive or large volume gynecologic malignancies, significant anatomical distortion, or recurrent disease. Such techniques are necessary components of the brachytherapy services available to patients with gynecologic malignancies giving superior results in terms of local tumor control and survival compared to those achieved with external beam alone or inadequate intracavitary applications. Local tumor control with an acceptable risk of complications can be achieved for these challenging disease presentations if these techniques are implemented skillfully through the joint efforts of the radiation oncologist and gynecologic surgeon.     

Chemical and microbial stability of fluid milk in response to packaging and dispensing

Chemical and microbiological stability of milk packaged in one litre pouches, a two litre paperboard box (with plastic liner) or a one gallon plastic jug were compared. The cardboard box gave the greatest protection against light induced lipid oxidation while significantly higher microbial populations were found in the larger containers (gallon jug and paperboard box) than in the smaller containers (one litre pouches) after one week of storage. Microbial populations were also greater in milk whose package had been opened and dispensed from previously than from milk found in an unopened package. These microbial data would suggest that one gallon of milk would remain fresher for the consumer when packaged in multi-unit packages than if packaged in one single container.     

Overcoming language barriers when teaching the Advanced Trauma Life Support course

OBJECTIVES: To determine whether blurred vision caused by exposure to triethylamine (TEA) can be detected by the measurement of contrast sensitivity. METHODS: 41 cold box core makers of three foundries and 82 control workers were examined. A detailed ocular and medical history was obtained from the subjects. The contrast sensitivity of the core makers was measured on Monday and Friday of the same week both before and immediately after work and also on a third day, when air samples of TEA were collected. Contrast sensitivity and visual acuity were measured by optotype figures at full contrast, 2.5% contrast, and 0.6% contrast. The changes in contrast sensitivity were used for the analysis. The results of binocular vision and the results of the dominant eye were analysed. Urine specimens for the analysis of TEA were collected on every occasion when contrast sensitivity was measured. RESULTS: 78% of the core makers had had symptoms of blurred vision, and 31% had had trouble driving or working. The breathing zone eight hour time weighted average TEA concentrations were 0.3-60 mg/m3. The mean urinary TEA concentration after the shift was 35 mmol/mol creatinine. Continuous monitoring showed high peaks of TEA leakage at a core making machine. Changes in binocular visual acuity did not differ between the exposed and unexposed workers. The contrast sensitivity decreased in 49% of the core makers and 21% of the controls (P = 0.002). CONCLUSIONS: The blurred vision caused by exposure to TEA can be documented by measuring contrast sensitivity. The mechanism by which TEA produces symptoms remains an issue of further study.     

A model for the porosity dependence of Young's modulus in brittle solids based on crack opening displacement

A crack opening displacement concept has been introduced to model the porosity dependence of Young's modulus in polycrystalline and single phase solids. In developing the theoretical model, it is assumed that each cylindrical cavity possesses radial cracks and spherical pores possess annular flaws. When an external stress is applied on such a solid, its elastic response is shown to be governed by the pore size, the width of an annular flaw, the number of pores (or pore volume fraction) and the flaw to pore size ratio. The validity of the present approach is tested against a number of experimental data.[/p]     

A limitation to the use of a constructive approach in the stability analysis of fixed-point digital controllers

A limitation to the application of a constructive algorithm to the stability analysis of fixed-point digital controllers is demonstrated by an example. The particular system analyzed consists of a fixed-point PI digital controller regulating a first-order process.