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A scale‐down mimic for mapping the process performance of centrifugation,depth and sterile filtration 下载免费PDF全文
Adrian Joseph Brian Kenty Michael Mollet Kenneth Hwang Steven Rose Stephen Goldrick Jean Bender Suzanne S. Farid Nigel Titchener‐Hooker 《Biotechnology and bioengineering》2016,113(9):1934-1941
In the production of biopharmaceuticals disk‐stack centrifugation is widely used as a harvest step for the removal of cells and cellular debris. Depth filters followed by sterile filters are often then employed to remove residual solids remaining in the centrate. Process development of centrifugation is usually conducted at pilot‐scale so as to mimic the commercial scale equipment but this method requires large quantities of cell culture and significant levels of effort for successful characterization. A scale‐down approach based upon the use of a shear device and a bench‐top centrifuge has been extended in this work towards a preparative methodology that successfully predicts the performance of the continuous centrifuge and polishing filters. The use of this methodology allows the effects of cell culture conditions and large‐scale centrifugal process parameters on subsequent filtration performance to be assessed at an early stage of process development where material availability is limited. Biotechnol. Bioeng. 2016;113: 1934–1941. © 2016 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. 相似文献
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Local contagion and regional compression: habitat selection drives spatially explicit,multiscale dynamics of colonisation in experimental metacommunities 下载免费PDF全文
Habitat selection, including oviposition site choice, is an important driver of community assembly in freshwater systems. Factors determining patch quality are assessed by many colonising organisms and affect colonisation rates, spatial distribution and community structure. For many species, the presence/absence of predators is the most important factor affecting female oviposition decisions. However, individual habitat patches exist in complex landscapes linked by processes of dispersal and colonisation, and spatial distribution of factors such as predators has potential effects beyond individual patches. Perceived patch quality and resulting colonisation rates depend both on risk conditions within a given patch and on spatial context. Here we experimentally confirm the role of one context‐dependent processes, spatial contagion, functioning at the local scale, and provide the first example of another context‐dependent process, habitat compression, functioning at the regional scale. Both processes affect colonisation rates and patterns of spatial distribution in naturally colonised experimental metacommunities. 相似文献
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Manuel J. Steinbauer Richard Field John‐Arvid Grytnes Panayiotis Trigas Claudine Ah‐Peng Fabio Attorre H. John B. Birks Paulo A. V. Borges Pedro Cardoso Chang‐Hung Chou Michele De Sanctis Miguel M. de Sequeira Maria C. Duarte Rui B. Elias José María Fernández‐Palacios Rosalina Gabriel Roy E. Gereau Rosemary G. Gillespie Josef Greimler David E. V. Harter Tsurng‐Juhn Huang Severin D. H. Irl Daniel Jeanmonod Anke Jentsch Alistair S. Jump Christoph Kueffer Sandra Nogué Rüdiger Otto Jonathan Price Maria M. Romeiras Dominique Strasberg Tod Stuessy Jens‐Christian Svenning Ole R. Vetaas Carl Beierkuhnlein 《Global Ecology and Biogeography》2016,25(9):1097-1107
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Clément Bougard Sébastien Moussay Stéphane Espié Damien Davenne 《Biological Rhythm Research》2016,47(3):401-415
The extent to which the diurnal fluctuations of different cognitive processes could be affected by sleep loss may be explored to predict performance decrements observed in the real world. Twenty healthy male subjects voluntarily took part in 8 test sessions at 06:00, 10:00, 14:00, and 18:00 h, following either a night with or without sleep in random order. Measurements included oral temperature, simple reaction time, sign cancelation, Go/NoGo, and the Purdue pegboard test. The results indicate that simple reaction time and motor coordination had morning–afternoon variations closely following the rhythms of temperature and vigilance. Inhibitory attention (Go/NoGo) presented no morning–afternoon variations. Sleep deprivation may affect the profiles of cognitive performance depending on the processes solicited. Sustained and inhibitory attention are particularly affected in the morning (after 24 and 28 waking hours), while a complex task (visuo-motor coordination) would be affected after 32 waking hours only. 相似文献
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为探讨个性化延续护理对2型糖尿病合并高血压患者生活质量及服药依从性影响,本研究选取2015年6月至2017年1月在哈励逊国际和平医院治疗的150例2型糖尿病合并高血压患者,随机分组,对照组患者应用常规护理,试验组患者给予个性化延续护理,观察比较两组患者血糖、血压、焦虑自评量表(self-rating anxiety scale, SAS)、抑郁自评量表(self-rating depression scale, SDS)、自尊量表(self-esteem scale,SES)、依从性差异。结果显示,12个月后试验组患者空腹血糖(7.59±1.26) mmol/L,糖化血红蛋白(glycated hemoglobin, HbAIC)(5.62±1.28)%较对照组明显下降(p<0.05);12个月后试验组患者收缩压(116.08±9.41) mmHg、舒张压(90.35±6.92) mmHg明显低于对照组(p<0.05);试验组患者SAS (35.13±4.27)分、SDS (31.42±2.09)分、SES (25.01±5.85)分同对照组比较明显改善(p<0.05);试验组患者依从性97.33%、不良生活习惯改善94.67%、健康知识掌握98.67%同对照组比较显著升高(p<0.05)。本研究结论初步表明针对2型糖尿病合并高血压患者应用个性化延续护理可改善患者血糖和血压水平,提高患者生活质量和治疗依从性,值得推广应用。 相似文献
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Hee Jae Hwang Joo Sung Kim Wook Kim Hyunwoo Park Divij Bhatia Eunsong Jee Yoon Sun Chung Do Hwan Kim Dukhyun Choi 《Liver Transplantation》2019,9(17)
A mechanosensitive, visco‐poroelastic polymer ion pump that can rapidly establish a dense electrical double layer via mechanical pressure, thereby significantly enhancing output performance of an ionic triboelectric nanogenerator (iTENG), is described. A working mechanism of an iTENG using a highly mechanosensitive, visco‐poroelastic ion pump is suggested and the optimal characteristics of the polymer ion pump are reported by investigating optical, mechanical, electrical, and electrochemical properties. Surprisingly, the pressure sensitivity of the iTENG reaches 23.3 V kPa?1, which is tens of times the record value. To achieve controlled high‐frequency pulses from an iTENG, kinematic systems using a gear train and a cam are integrated with a single grounded iTENG, which produces a maximum of 600 V and 22 mA (≈2.2 W cm?2) at an input frequency of 1.67 Hz; after power transforming, those values are converted to 1.42 V and 225 mA. A capacitor of 1 mF can be fully charged to 2 V in only 60 s, making it possible to continuously operate a wireless‐communicating self‐powered humidity sensor. Also, due to the high transparency and deformability of the polymer ion pump, a self‐powered transparent tactile sensor is successfully assembled using a 5 × 5 iTENG array. 相似文献
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