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1.
In the 1960s the promise of the Brantigan lung reduction surgery was shattered when it was shown that the improvement in airway conductance drifted back towards the preoperative value over a period of 12 to 18 months. Since then there has been a marked improvement in our understanding of emphysema, its pathology, and techniques for obtaining images of the lung. In addition, reliable automated cardiopulmonary and physiologic testing, advances in critical care medicine, and new pharmacologic agents have improved patient care. Surgical techniques now allow better control of air leaks and access to anatomic regions not previously accessible. The combination of all of the above makes lung reduction surgery worth re-examining as a palliative procedure for severely symptomatic patients. Clearly, it is not a panacea but can in some cases produce dramatic improvements in symptomatology and quality of life. This article presents the available data describing potential mechanisms of improvement and clinical outcomes following lung reduction surgery. It also outlines areas that need further work, such as patient selection and surgical techniques. 相似文献
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Luther B.M. Yong Wang Larotonda M.A. Alessi D. Berrill M. Rocca J.J. Dunn J. Keenan R. Shlyaptsev V.N. 《Quantum Electronics, IEEE Journal of》2006,42(1):4-13
We discuss the demonstration of gain-saturated high repetition rate table-top soft X-ray lasers producing microwatt average powers at wavelengths ranging from 13.9 to 33 nm. The results were obtained heating a precreated plasma with a picosecond optical laser pulse impinging at grazing incidence onto a precreated plasma. This pumping geometry increases the energy deposition efficiency of the pump beam into the gain region, making it possible to saturate soft X-ray lasers in this wavelength range with a short pulse pump energy of only 1 J at 800-nm wavelength. Results corresponding to 5-Hz repetition rate operation of gain-saturated 14.7-nm Ni-like Pd and 32.6-nm line Ne-like Ti lasers pumped by a table-top Ti:sapphire laser are reported. We also discuss results obtained using a 1 /spl omega/1054-nm prepulse and 2 /spl omega/527-nm short pulse from a Nd:glass pump laser. This work demonstrates the feasibility of producing compact high average power soft X-ray lasers for applications. 相似文献
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In an earlier set of studies with a different Intelligently Coached Simulation (Orey, M.A., Fan, H., Park, J., Tzeng, S., & Gustafson, K. (1995). Evaluation of Device operator in a context of a coached simulation environment), we found a retention and a transfer problem. We tried to solve these problems while building a new Intelligently Coached Simulation (the SINCGARS Tutor). The solutions to the two problems were to use an interactive conceptual model for the retention problem and we used photographs of the equipment as the visuals of the simulation. We then tested this new tutor with a group of 22 officers who were not only required to know how to operate the SINCGARS radio, but would be responsible for teaching others in their unit when their training was complete. We had one group of officers train on the real equipment, in pairs, with one instructor available for guidance. The other group of 11 learned via the SINCGARS Tutor. The post test was to put an actual radio into operation while being observed by a trained observer. Results indicate that not only did the transfer problem go away, but officers trained on the computer performed the task more accurately both initially on the immediate post test and again on a surprise four-week delayed post test. The SINCGARS Tutor was found to be a very good training solution. 相似文献
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Fruit smoothie samples were thermally (P70 > 10 min) or high hydrostatic pressure (HHP) processed (450 MPa/20 °C/5 min or 600 MPa/20 °C/10 min) and the total antioxidant capacity (TAC), levels of antioxidant groups [total phenols (TP), anthocyanins and ascorbic acid], instrumental colour, polyphenol oxidase (PPO) enzyme activity and dissolved oxygen were examined over a storage period of 10 h at 4 °C. Thermal processing of smoothies reduced (p < 0.001) TAC and TP values, ascorbic acid and L and a colour attributes (lightness and redness respectively) compared to fresh and HHP-450 processed samples. Conversely, it did result in complete inactivation of PPO enzyme, with no activity detected. Of the HHP treatments, HHP-450 samples had higher (p < 0.001) levels of total antioxidant, phenols and anthocyanin content than HHP-600 samples. However, the latter was more effective in reducing (p < 0.001) the endogenous enzyme activity of the smoothies. .Ascorbic acid content degraded over the storage for all smoothies. HHP-600 samples had high initial values, which declined slowly over storage, while thermal samples had the lowest initial value (0.5 h) that fell below detectable limits by 10 h. Despite these data, less pronounced effects were observed for storage. No significant effects were observed for total anthocyanin and phenolic contents as well as L and colour change (ΔE) variables. Overall, HHP processing of smoothies at moderate temperatures may be a suitable alternative to traditional thermal processing. 相似文献
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Simultaneous delivery of antibiotics neomycin and ampicillin in drinking water inhibits fermentation of resistant starch in rats 下载免费PDF全文
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Jesse M. Keenan 《Building Research & Information》2016,44(4):407-422
This paper is premised on a conceptual framework that attempts to draw theoretical and practical connections between sustainability, resilience and adaptation. The framework is explored through a case study of the corporate real estate (property) strategies of Goldman Sachs (a multinational investment banking and investment management company) developed over the course of the consolidation and development of its corporate headquarters. This case seeks to identify the existence and nature of the relationships by and between sustainable corporate real estate strategies, resilient operations planning and the firm's adaptive capacity. A secondary proposition seeks to evaluate whether the capacity of the firm to adapt and be resilient to changing conditions has been positively advanced by the firm's sustainable corporate real estate strategies. The findings support the proposition that these connections do exist, as well as the proposition that sustainability was promoting adaptive capacity and operational resilience. However, it remains an open question to what extent these practices and capacities are deterministic of one another. This paper sets the stage for future research that seeks to measure and model organizational adaptive capacity and to understand the potential co-benefits that may serve the interests of firms who struggle to rationalize the costs of sustainability. 相似文献
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Three experiments were carried out to determine whether there is a lag in predicting surprise relative to false belief. All 3 experiments used "backwards reasoning" tasks. The findings were that ( a ) there is a lag in predicting surprise relative to false belief, ( b ) by 5 or 6 years of age children claim that one will be surprised when they gain knowledge of that which they were previously ignorant or when they discover that they had previously held a false belief, ( c ) by 7 to 9 years of age they understand that surprise will more likely result from false beliefs rather than mere ignorance, and ( d ) children's difficulty understanding surprise as specifically belief-based does not likely stem from information processing limitations. It is argued that the lag likely results because children must build a new concept of surprise ( e.g., from desire- to belief-based ) . (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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