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21.
Kornelis Blok 《Journal of Industrial Ecology》2004,8(4):87-99
Reduction of specific energy consumption by 1% to 2% per year is typically what is considered feasible for end-use energy applications. This article tries to answer the question of whether much higher rates, for example 5% and more, are feasible for new equipment, installations, and buildings.
After examining some end-use functions in industry, buildings, and the transport sector, it is concluded that for the foreseeable future—that is, not more than 10 to 20 years into the future—such high rates of reduction of specific energy consumption are indeed possible. For the longer term, no definitive proof is available, but there are also no indications that such high rates could not be maintained.
The effect of the reduction of specific energy consumption on total energy use depends on the growth of energy-using activities and on the replacement rates of capital stock. Taking these into account, it is estimated that for industrialized countries a reduction of absolute total energy use by 50% in 50 years compared with the current levels is possible.
Such a reduction requires a huge effort in innovation; however, the possibilities for stimulating innovation seem not to be exhausted yet. 相似文献
After examining some end-use functions in industry, buildings, and the transport sector, it is concluded that for the foreseeable future—that is, not more than 10 to 20 years into the future—such high rates of reduction of specific energy consumption are indeed possible. For the longer term, no definitive proof is available, but there are also no indications that such high rates could not be maintained.
The effect of the reduction of specific energy consumption on total energy use depends on the growth of energy-using activities and on the replacement rates of capital stock. Taking these into account, it is estimated that for industrialized countries a reduction of absolute total energy use by 50% in 50 years compared with the current levels is possible.
Such a reduction requires a huge effort in innovation; however, the possibilities for stimulating innovation seem not to be exhausted yet. 相似文献
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Peter M. O'Callaghan Maud E. Berthelot Robert J. Young James W.A. Graham Andrew J. Racher Dulce Aldana 《Biotechnology progress》2015,31(5):1187-1200
Much effort has been expended to improve the capabilities of individual Chinese hamster ovary (CHO) host cell lines to synthesize recombinant therapeutic proteins (rPs). However, given the increasing variety in rP molecular types and formats it may be advantageous to employ a toolbox of CHO host cell lines in biomanufacturing. Such a toolbox would contain a panel of hosts with specific capabilities to synthesize certain molecular types at high volumetric concentrations and with the correct product quality (PQ). In this work, we examine a panel of clonally derived host cell lines isolated from CHOK1SV for the ability to manufacture two model proteins, an IgG4 monoclonal antibody (Mab) and an Fc‐fusion protein (etanercept). We show that these host cell lines vary in their relative ability to synthesize these proteins in transient and stable pool production format. Furthermore, we examined the PQ attributes of the stable pool‐produced Mab and etanercept (by N‐glycan ultra performance liquid chromatography (UPLC) and liquid chromatography ‐ tandem mass spectrometry (LC‐MS/MS), respectively), and uncovered substantial variation between the host cell lines in Mab N‐glycan micro‐heterogeneity and etanercept N and O‐linked macro‐heterogeneity. To further investigate the capabilities of these hosts to act as cell factories, we examined the glycosylation pathway gene expression profiles as well as the levels of endoplasmic reticulum (ER) and mitochondria in the untransfected hosts. We uncovered a moderate correlation between ER mass and the volumetric product concentration in transient and stable pool Mab production. This work demonstrates the utility of leveraging diversity within the CHOK1SV pool to identify new host cell lines with different performance characteristics. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1187–1200, 2015 相似文献
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Laetitia Malphettes Yevgeniy Freyvert Jennifer Chang Pei‐Qi Liu Edmond Chan Jeffrey C. Miller Zhe Zhou Thu Nguyen Christina Tsai Andrew W. Snowden Trevor N. Collingwood Philip D. Gregory Gregory J. Cost 《Biotechnology and bioengineering》2010,106(5):774-783
IgG1 antibodies produced in Chinese hamster ovary (CHO) cells are heavily α1,6‐fucosylated, a modification that reduces antibody‐dependent cellular cytotoxicity (ADCC) and can inhibit therapeutic antibody function in vivo. Addition of fucose is catalyzed by Fut8, a α1,6‐fucosyltransferase. FUT8?/? CHO cell lines produce completely nonfucosylated antibodies, but the difficulty of recapitulating the knockout in protein‐production cell lines has prevented the widespread adoption of FUT8?/? cells as hosts for antibody production. We have created zinc‐finger nucleases (ZFNs) that cleave the FUT8 gene in a region encoding the catalytic core of the enzyme, allowing the functional disruption of FUT8 in any CHO cell line. These reagents produce FUT8?/? CHO cells in 3 weeks at a frequency of 5% in the absence of any selection. Alternately, populations of ZFN‐treated cells can be directly selected to give FUT8?/? cell pools in as few as 3 days. To demonstrate the utility of this method in bioprocess, FUT8 was disrupted in a CHO cell line used for stable protein production. ZFN‐derived FUT8?/? cell lines were as transfectable as wild‐type, had similar or better growth profiles, and produced equivalent amounts of antibody during transient transfection. Antibodies made in these lines completely lacked core fucosylation but had an otherwise normal glycosylation pattern. Cell lines stably expressing a model antibody were made from wild‐type and ZFN‐generated FUT8?/? cells. Clones from both lines had equivalent titer, specific productivity distributions, and integrated viable cell counts. Antibody titer in the best ZFN‐generated FUT8?/? cell lines was fourfold higher than in the best‐producing clones of FUT8?/? cells made by standard homologous recombination in a different CHO subtype. These data demonstrate the straightforward, ZFN‐mediated transfer of the Fut8? phenotype to a production CHO cell line without adverse phenotypic effects. This process will speed the production of highly active, completely nonfucosylated therapeutic antibodies. Biotechnol. Bioeng. 2010;106: 774–783. © 2010 Wiley Periodicals, Inc. 相似文献
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探讨疣粒野生稻应答黄单胞杆菌水稻致病变种(Xoo)的基因芯片制作,通过芯片杂交筛选抗病相关基因。芯片含有2436个片段,来自于应答撖)O的疣粒野生稻差减文库和cDNA文库,通过芯片杂交及微阵列分析基因表达,选其中800个样品点测序比对。其中,35个无同源序列,大部分有同源序列的功能未知,已知功能的序列中明显上调表达的基因有:富含脯氨酸蛋白、泛素连接酶、伸展蛋白、谷胱甘肽S-转移酶II、脂类转移酶等,明显下调表达的基因有:细胞色素P450单加氧酶、醛缩酶、金属硫蛋白、硫氧还蛋白、热激蛋白等,表达无明显变化的基因有:抗坏血酸过氧化物酶、转铜伴侣、脂酶、花丝温敏H2A蛋白等。高通量基因芯片的利用及微阵列分析是筛选抗病相关基因、获取大量抗病相关信息的有效手段。 相似文献
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Jens H. Vogel Huong Nguyen Roberto Giovannini Jolene Ignowski Steve Garger Anil Salgotra Jennifer Tom 《Biotechnology and bioengineering》2012,109(12):3049-3058
Complex biopharmaceuticals, such as recombinant blood coagulation factors, are addressing critical medical needs and represent a growing multibillion‐dollar market. For commercial manufacturing of such, sometimes inherently unstable, molecules it is important to minimize product residence time in non‐ideal milieu in order to obtain acceptable yields and consistently high product quality. Continuous perfusion cell culture allows minimization of residence time in the bioreactor, but also brings unique challenges in product recovery, which requires innovative solutions. In order to maximize yield, process efficiency, facility and equipment utilization, we have developed, scaled‐up and successfully implemented a new integrated manufacturing platform in commercial scale. This platform consists of a (semi‐)continuous cell separation process based on a disposable flow path and integrated with the upstream perfusion operation, followed by membrane chromatography on large‐scale adsorber capsules in rapid cycling mode. Implementation of the platform at commercial scale for a new product candidate led to a yield improvement of 40% compared to the conventional process technology, while product quality has been shown to be more consistently high. Over 1,000,000 L of cell culture harvest have been processed with 100% success rate to date, demonstrating the robustness of the new platform process in GMP manufacturing. While membrane chromatography is well established for polishing in flow‐through mode, this is its first commercial‐scale application for bind/elute chromatography in the biopharmaceutical industry and demonstrates its potential in particular for manufacturing of potent, low‐dose biopharmaceuticals. Biotechnol. Bioeng. 2012; 109: 3049–3058. © 2012 Wiley Periodicals, Inc. 相似文献
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《Saudi Journal of Biological Sciences》2017,24(4):787-796
The current study was aimed to fabricate customized root form dental implant using additive manufacturing technique for the replacement of missing teeth. The root form dental implant was designed using Geomagic™ and Magics™, the designed implant was directly manufactured by layering technique using ARCAM A2™ electron beam melting system by employing medical grade Ti–6Al–4V alloy powder. Furthermore, the fabricated implant was characterized in terms of certain clinically important parameters such as surface microstructure, surface topography, chemical purity and internal porosity. Results confirmed that, fabrication of customized dental implants using additive rapid manufacturing technology offers an attractive method to produce extremely pure form of customized titanium dental implants, the rough and porous surface texture obtained is expected to provide better initial implant stabilization and superior osseointegration. 相似文献