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31.
Environmental management, being an important component in strategies for achieving sustainable development of processes and products, has emerged as a proactive approach in majority of the manufacturing organizations. From the strategic perspective environmentally conscious manufacturing (ECM) programs lead to better environmental management practice. The objective of the current paper is to present an integrated and holistic framework to evaluate ECM programs. This framework combines three multi-criteria decision analysis (MCDA) methods to consider eight major environmentally conscious manufacturing indicators (ECMI) in order to identify the efficiency of each ECM program. First the interdependence relationship among the ECMIs is established using decision-making trail and evaluation laboratory (DEMATEL). Then a range of weightage (i.e. upper and lower bounds) is created for each ECMI using analytic network process (ANP) to include managerial preferences. Finally, this range of weightage for each indicator is applied to perform restricted multiplier data envelopment analysis (RMDEA). Results show that the technical efficiency of the inefficient ECM programs for integrated RMDEA, on average, is calculated as 53.2% whereas traditional input oriented DEA provides the same score as 72.3%. This clearly indicates that integrated RMDEA is better than the input oriented DEA because same level of output could be produced with lesser resources if the ECM programs perform on the frontier. Hence, the advantage of this methodology is that the managerial preferences are successfully implemented through this newly developed hybrid methodology that will help to reduce less resource consumption and lead to better environmental policy.  相似文献   
32.
Transfer printing is a method to transfer solid micro/nanoscale materials (herein called ‘inks’) from a substrate where they are generated to a different substrate by utilizing elastomeric stamps. Transfer printing enables the integration of heterogeneous materials to fabricate unexampled structures or functional systems that are found in recent advanced devices such as flexible and stretchable solar cells and LED arrays. While transfer printing exhibits unique features in material assembly capability, the use of adhesive layers or the surface modification such as deposition of self-assembled monolayer (SAM) on substrates for enhancing printing processes hinders its wide adaptation in microassembly of microelectromechanical system (MEMS) structures and devices. To overcome this shortcoming, we developed an advanced mode of transfer printing which deterministically assembles individual microscale objects solely through controlling surface contact area without any surface alteration. The absence of an adhesive layer or other modification and the subsequent material bonding processes ensure not only mechanical bonding, but also thermal and electrical connection between assembled materials, which further opens various applications in adaptation in building unusual MEMS devices.  相似文献   
33.
Herbal remedies were the first medicines used by humans due to the many pharmacologically active secondary metabolites produced by plants. Some of these metabolites inhibit cell division and can therefore be used for the treatment of cancer, e.g. the mitostatic drug paclitaxel (Taxol). The ability of plants to produce medicines targeting cancer has expanded due to the advent of genetic engineering, particularly in recent years because of the development of gene editing systems such as the CRISPR/Cas9 platform. These technologies allow the introduction of genetic modifications that facilitate the accumulation of native pharmaceutically-active substances, and even the production heterologous recombinant proteins, including human antibodies, lectins and vaccine candidates. Here we discuss the anti-cancer agents that are produced by plants naturally or following genetic modification, and the potential of these products to supply modern healthcare systems. Special emphasis will be put on proteinaceous anti-cancer agents, which can exhibit an improved selectivity and reduced side effects compared to small molecule-based drugs.  相似文献   
34.
An integrated all flow-through technology platform for the purification of therapeutic monoclonal antibodies (mAb), consisting of activated carbon and flow-through cation and anion exchange chromatography steps, can replace a conventional chromatography platform. This new platform was observed to have excellent impurity clearance at high mAb loadings with overall mAb yield exceeding 80%. Robust removal of DNA and host cell protein was demonstrated by activated carbon and a new flow-through cation exchange resin exhibited excellent clearance of mAb aggregate with high monomer recoveries. A ten-fold improvement of mAb loading was achieved compared to a traditional cation exchange resin designed for bind and elute mode. High throughput 96-well plate screening was used for process optimization, focusing on mAb loading and solution conditions. Optimum operating windows for integrated flow-through purification are proposed based on performance characteristics. The combination of an all flow-through polishing process presents significant opportunities for improvements in facility utilization and process economics.  相似文献   
35.
The major purpose of this article is to construct a plausible emissions profile for the European chemical industry from process data and mass balance considerations.' In it we describe this industry and its major conversion processes and emissions. Four major process chains, beginning with methane, ethylene, propylene, and benzene are analyzed, along with five important stand-alone processes. A self-consistent version of the industry is constructed for 1992, based on data from a variety of sources.
In 1992 Europe consumed 9,297 metric kilotons as measured by weight of chlorine (kMT[CI]) of salt and 2 I I kMT(CI) of recycled hydrochloric acid (HCI) to produce 86 I0 kMT of virgin elemental chlorine, plus 278 kMT(CI) of virgin by-product HCI. Total chlorine input to the industry was 8,689 kMT including I2 kMT(CI) of recycled chlorinated hydrocarbons (CHCs) and (net) 79 kMT(CI) of HCI. Shipments of chlorine and HCI to other sectors was 1,367 kMT(CI), while 7,322 kMT(CI) was embodied in products or lost within the sector: Of this subtotal, 350 kMT(CI) was used to manufacture identified inorganic chemicals, 5,694 kMT(CI) for identified organic chemicals, and 1,278 kMT(CI) for "other unspecified" chemicals.
We estimate that products account for 41.6% of inputs (measured at the "fence"), while wastes account for 24.7%  相似文献   
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37.
Vaccine manufacturing strategies that lower capital and production costs could improve vaccine access by reducing the cost per dose and encouraging localized manufacturing. Continuous processing is increasingly utilized to drive lower costs in biological manufacturing by requiring fewer capital and operating resources. Aqueous two-phase systems (ATPS) are a liquid–liquid extraction technique that enables continuous processing for viral vectors. To date, no economic comparison between viral vector purifications using traditional methods and ATPS has been published. In this work, economic simulations of traditional chromatography-based virus purification were compared to ATPS-based virus purification for the same product output in both batch and continuous modes. First, the modeling strategy was validated by re-creating a viral subunit manufacturing economic simulation. Then, ATPS capital and operating costs were compared to that of a traditional chromatography purification at multiple scales. At all scales, ATPS purification required less than 10% of the capital expenditure compared to chromatography-based purification. At an 11 kg per year production scale, the ATPS production costs were 50% less than purification with chromatography. Other chromatography configurations were explored, and may provide a production cost benefit to ATPS, but the purity and recovery were not experimentally verified. Batch and continuous ATPS were similar in capital and production costs. However, manual price adjustments suggest that continuous ATPS plant-building costs could be less than half that of batch ATPS at the 11 kg per year production scale. These simulations show the significant reduction in manufacturing costs that ATPS-based purification could deliver to the vaccine industry.  相似文献   
38.
Bispecific antibodies (BsAbs) are emerging as an important class of biopharmaceutical. The majority of BsAbs are created from conventional antibodies or fragments engineered into more complex configurations. A recurring challenge in their development, however, is the identification of components that are optimised for inclusion in the final format in order to deliver both efficacy and robust biophysical properties. Using a modular BsAb format, the mAb-dAb, we assessed whether an ‘in-format’ screening approach, designed to select format-compatible domain antibodies, could expedite lead discovery. Human nerve growth factor (NGF) was selected as an antigen to validate the approach; domain antibody (dAb) libraries were screened, panels of binders identified, and binding affinities and potencies compared for selected dAbs and corresponding mAb-dAbs. A number of dAbs that exhibited high potency (IC50) when assessed in-format were identified. In contrast, the corresponding dAb monomers had ~1000-fold lower potency than the formatted dAbs; such dAb monomers would therefore have been omitted from further characterization. Subsequent stoichiometric analyses of mAb-dAbs bound to NGF, or an additional target antigen (vascular endothelial growth factor), suggested different target binding modes; this indicates that the observed potency improvements cannot be attributed simply to an avidity effect offered by the mAb-dAb format. We conclude that, for certain antigens, screening naïve selection outputs directly in-format enables the identification of a subset of format-compatible dAbs, and that this offers substantial benefits in terms of molecular properties and development time.  相似文献   
39.
Manufacturing procedures for cellular therapies are continuously improved with particular emphasis on product safety. We previously developed a dendritic cell (DC) cancer vaccine technology platform that uses clinical grade lipopolysaccharide (LPS) and interferon (IFN)-y for the maturation of monocyte derived DCs. DCs are frozen after 6 hrs exposure at a semi-mature stage (smDCs) retaining the capacity to secret interleukin (IL)-12 and thus support cytolytic T-cell responses, which is lost at full maturation. We compared closed systems for monocyte enrichment from leucocyte apheresis products from healthy individuals using plastic adherence, CD14 selection, or CD2/19 depletion with magnetic beads, or counter flow centrifugation (elutriation) using a clinical grade in comparison to a research grade culture medium for the following DC generation. We found that elutriation was superior compared to the other methods showing 36 ± 4% recovery, which was approximately 5-fold higher as the most frequently used adherence protocol (8 ± 1%), and a very good purity (92 ± 5%) of smDCs. Immune phenotype and IL-12 secretion (adherence: 1.4 ± 0.4; selection: 20 ± 0.6; depletion: 1 ±0.5; elutriation: 3.6 ± 1.5 ng/ml) as well as the potency of all DCs to stimulate T cells in an allogeneic mixed leucocyte reaction did not show statistically significant differences. Research grade and clinical grade DC culture media were equally potent and freezing did not impair the functions of smDCs. Finally, we assessed the functional capacity of DC cancer vaccines manufactured for three patients using this optimized procedure thereby demonstrating the feasibility of manufacturing DC cancer vaccines that secret IL-12 (9.4 ± 6.4 ng/ml). We conclude that significant steps were taken here towards clinical grade DC cancer vaccine manufacturing.  相似文献   
40.
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