首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The sciences of industrial ecology, complex systems, and adaptive management are intimately related, since they deal with flows and dynamic interdependencies between system elements of various kinds. As such, the tool kit of complex systems science could enrich our understanding of how industrial ecosystems might evolve over time. In this article, I illustrate how an important tool of complex systems science— agent-based simulation —can help to identify those potential elements of an industrial ecosystem that could work together to achieve more eco-efficient outcomes. For example, I show how agent-based simulation can generate cost-efficient energy futures in which groups of firms behave more eco-efficiently by introducing strategically located clusters of renewable, low-emissions, distributed generation. I then explain how role-playing games and participatory modeling can build trust and reduce conflict about the sharing of common-pool resources such as water and energy among small clusters of evolving agents. Collective learning can encourage potential industrial partners to gradually cooperate by exchanging by-products and/or sharing common infrastructure by dint of their close proximity. This kind of coevolutionary learning, aided by participatory modeling, could help to bring about industrial symbiosis.  相似文献   

2.
We have used a 692 case dataset, collected retrospectively by a single observer, to develop decision support systems for the cytodiagnosis of fine needle aspirates of breast lesions. In this study, we use a 322 case dataset that was prospectively collected by multiple observers in a working clinical environment to test two predictive systems, using logistic regression and the multilayer perceptron (MLP) type of neural network. Ten observed features and the patient age were used as input features. The systems were developed using a training set and test set from the single observer dataset and then applied to the multiple observer dataset. For the independent test cases from the single observer dataset, with a threshold set for no false positives on the training set, logistic regression produced a sensitivity of 82% (95% confidence interval 73-91) and a predictive value of a positive result (PV +) of 98% (95-99), the values for the MLP were 79% (69-89) and 100%, respectively. However the performance on the prospective multiple observer dataset was much worse, with a sensitivity of 72% (65-80), and PV + of 97% (94-99) for logistic regression and 67% (60-75) and 91% (85-97) for the MLP. These results suggest that there is considerable interobserver variability for the defined features and that this system is unsuitable for further development in the clinical environment unless this problem can be overcome.  相似文献   

3.
We reflect on our experiences in developing and teaching industrial ecology to interdisciplinary classes of M.Sc. and Ph.D. students. During a three-year period different ways of teaching a course in industrial ecology were tested. We conclude that an industrial ecology course has positive effects on the students' ability to acquire a holistic understanding of life-cycle environmental performance, a skill much in demand by industry. Such a course should be based on problem-oriented learning. We recommend the use of thematically-focused seminars with time for both lectures and workshops. We found that substantial participation by teachers from different disciplines and partners from industry and government is very effective. Such a course also facilitates a broader process of change within the university. Implementing industrial ecology in the university requires a joint effort and collaboration among various faculties and departments, where research activities, student projects, as well as regular student teaching and tutoring, must be complementary elements of a major interdisciplinary strategy. Such a strategy has been employed at the Norwegian University of Science and Technology (NTNU) since the first initiatives in this area were taken in 1993, and this has led to our present more comprehensive Industrial Ecology Programme (IndEcol).  相似文献   

4.
Models of eco‐industrial parks (EIPs) might help us transform our production systems by fostering the emergence of sustainable EIPs since such models have the potential to support the decision‐making processes of cooperative companies that participate and to decrease operational uncertainties. In this article, a conceptual framework for modeling the operation of EIPs is presented. The framework is underpinned by complex adaptive systems theory, industrial ecology, and an analysis of the experiences of existing EIPs. The proposed framework draws on the observed strengths of two types of industrial symbiosis models—planned eco‐industrial parks (PEIPs) and EIPs that developed through self‐organizing symbiosis (SOS)—as well as their observed weaknesses and the features of complex adaptive systems. From this analysis, five key properties to be modeled are deduced: functionality, reliability, life span, theoretical knowledge, and adaptability. It is proposed that the properties of functionality and theoretical knowledge are determined by the goals of the EIP and its member companies, while the property of adaptability is determined by the understanding that the companies in an EIP have of the environment surrounding the EIP, while the properties of reliability and life span are determined by the internal and external relationships of the companies that make up an EIP.  相似文献   

5.
Cooling water systems (CWS) are one of the main energy and water using operations in industry. Existing CWS in operation provide high improvement potentials in environmental and economic performance through optimized operation and system control. Industry often fails to realize these potentials, given that the efficiency measures as well as their technical, economic, and ecological impact are mostly unknown because of the lack of appropriate approaches. This article presents a holistic approach to the systematic identification and assessment of efficiency measures that support industry in improving the operation and system control of large‐scale CWS consisting of one or multiple cooling towers, heat exchangers, and pumps. Based on material flow analysis coupled with process modeling, a material and energy flow model of CWS is developed. The model enables the investigation of different adjustments in operation of CWS in order to identify and assess specific efficiency measures. The approach is applied to a CWS of a real manufacturing facility. The results show, first, high validity of the approach as compared to a real system. Second, the effectiveness of the approach, given that the model allows fast and simple identification and assessment of efficiency measures that save up to 16% energy and 24% water in the presented case study.  相似文献   

6.
地理信息系统及其在动物空间行为研究中的应用   总被引:1,自引:0,他引:1  
空间属性是动物行为的重要特征,也是行为生态学研究中必须要面对的难题之一。地理信息系统(Geographic Information System,GIS)具有强大的空间分析功能,它在动物行为生态学研究中得到了越来越广泛的应用,如生境选择、领域分析、迁徙路线、活动节律等。本文较系统地阐述了GIS的原理以及在行为生态学研究中所涉及的基本概念和原理,对近年来利用GIS进行的行为生态学研究做了回顾和总结,并对其未来的发展进行了展望。  相似文献   

7.
Two new manganese(II) complexes, [Mn(L1)(L1H)(ClO4)(H2O)][ClO4]2·0.5CH3CN·H2O (1) [L1 = trans-(±)2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1H-imidazol-4-yl)pyridine)] and [Mn2(μ-L2)2(H2O)3(CH3CN)3][ClO4]4·2CH3CN (2) [L2 = cis-(±)2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1H-imidazol-4-yl)pyridine)], have been prepared and examined by single-crystal X-ray diffraction analysis, showing that complex 1 is a mononuclear compound, whereas complex 2 is a dinuclear species. The cis/trans isomers L1 and L2 have similar coordination properties, but behave as bidentate and tridentate chelating ligands, respectively, giving distorted octahedral metal coordination geometries. X-ray diffraction studies revealed that the molecular and crystal structures are stabilized by a series of intra- and intermolecular interactions. In both cases extended supramolecular networks are generated, in compound 1 through O-H···O, O-H···N, N-H···O, N-H···N, C-H···O, C-H···N, C-H···π and π···π interactions, and in compound 2 through O-H···O, O-H···N, C-H···O and π···π interactions. The observed structural differences between the two metal complexes might be a consequence of these stabilizing effects.  相似文献   

8.
The interaction between [Pd(But-dtc)(phen)]NO3 (where But-dtc = butyldithiocarbamate and phen = 1,10-phenanthroline) with HSA (Human Serum Albumin) was investigated by applying fluorescence, UV–Vis and circular dichroism techniques under physiological conditions. The results of fluorescence spectra indicated that the Pd(II) complex could effectively quench the fluorescence intensity of HSA molecules via static mechanism. The number of binding sites and binding constant of HSA–Pd(II) complex were calculated. Analysis of absorption titration data on the interaction between Pd(II) complex and HSA revealed the formation of HSA–Pd(II) complex with high-binding affinity. Thermodynamic parameters indicated that hydrophobic forces play a major role in this interaction. Furthermore, CD measurements were taken to explore changes in HSA secondary structure induced by the Pd(II) complex.  相似文献   

9.
Fed-batch and perfusion culture dominate mammalian cell culture production processes. In this paper, a decision-support tool was employed to evaluate the economic feasibility of both culture modes via a case study based upon the large-scale production of monoclonal antibodies. The trade-offs between the relative simplicity but higher start-up costs of fed-batch processes and the high productivity but higher chances of equipment failure of perfusion processes were analysed. Deterministic analysis showed that whilst there was an insignificant difference (3%) between the cost of goods per gram (COG/g) values, the perfusion option benefited from a 42% reduction in capital investment and a 12% higher projected net present value (NPV). When Monte Carlo simulations were used to account for uncertainties in titre and yield, as well as the risks of contamination and filter fouling, the frequency distributions for the output metrics revealed that neither process route offered the best of both NPV or product output. A product output criterion was formulated and the options that met the criterion were compared based on their reward/risk ratio. The perfusion option was no longer feasible as it failed to meet the product output criterion and the fed-batch option had a 100% higher reward/risk ratio. The tool indicated that in this particular case, the probabilities of contamination and fouling in the perfusion option need to be reduced from 10% to 3% for this option to have the higher reward/risk ratio. The case study highlighted the limitations of relying on deterministic analysis alone.  相似文献   

10.
Serum albumins (human serum albumin (HSA) and bovine serum albumin (BSA), two main circulatory proteins), are globular and monomeric macromolecules in plasma that transport many drugs and compounds. In the present study, we investigated the interactions of the Tb(III)–quercetin (Tb–QUE) complex with HSA and BSA using common spectroscopic techniques and a molecular docking study. Fluorescence data revealed that the inherent fluorescence emission of HSA and BSA was markedly quenched by the Tb–QUE complex through a static quenching mechanism, confirming stable complex formation (a ground‐state association) between albumins and Tb–QUE. Binding and thermodynamic parameters were obtained from the fluorescence spectra and the related equations at different temperatures under biological conditions. The binding constants (Kb) were calculated to be 0.8547 × 103 M?1 for HSA and 0.1363 × 103 M?1 for BSA at 298 K. Also, the number of binding sites (n) of the HSA/BSA–Tb–QUE systems was obtained to be approximately 1. Thermodynamic data calculations along with molecular docking results indicated that electrostatic interactions have a main role in the binding process of the Tb–QUE complex with HSA/BSA. Furthermore, molecular docking outputs revealed that the Tb–QUE complex has high affinity to bind to subdomain IIA of HSA and BSA. Binding distances (r) between HSA–Tb–QUE and BSA–Tb–QUE systems were also calculated using the Forster (fluorescence resonance energy transfer) method. It is expected that this study will provide a pathway for designing new compounds with multiple beneficial effects on human health from the phenolic compounds family such as the Tb–QUE complex.  相似文献   

11.
The localization of -D-galactose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine sugar residues of glycoconjugates in the vomeronasal organ, olfactory mucosa, and septal organ in the nasal mucosae of rats was investigated using lectinohistochemical techniques combined with bright-field, epifluorescence, and confocal laser scanning microscopy. Glycoconjugates in the mucomicrovillar complex of the vomeronasal organ contained all the sugar residues investigated, whereas glycoconjugates in the mucociliary complex of the olfactory mucosa and septal organ contained only N-acetyl-D-glucosamine. Vomeronasal receptor neurons expressed glycoconjugates with terminal -D-galactose and -N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine residues, whereas olfactory and septal receptor neurons expressed glycoconjugates with only N-acetyl-D-glucosamine residues. Secretory granules of glands of the vomeronasal organ contained glycoconjugates with terminal -D-galactose and N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine, whereas those of the Bowman's glands and glands of septal organ contained glycoconjugates with only internal N-acetyl-D-glucosamine residues. The results demonstrate that the glycoconjugates expressed by vomeronasal receptor neurons and glands contain terminal -D-galactose and -N-acetyl-D-galactosamine sugar residues that are not expressed by analogous cells in the olfactory mucosa and septal organ.  相似文献   

12.
Shigeru Itoh 《BBA》1984,766(2):464-471
Large blue-shifts of carotenoid absorption bands were induced by dark addition of a hydrophobic anion, tetraphenylborate, in chromatophores and cell membranes of photosynthetic bacteria, Rhodopseudomonas sphaeroides and Rhodopseudomonas capsulata. Tetraphenylborate also induced a red-shift of the 850 nm absorption band and a blue-shift and broadening of the 800 nm band of bacteriochlorophyll. From the analysis of the relation between the magnitude and isosbestic wavelength of the absorbance changes the tetraphenylborate-induced carotenoid band shift were assumed to reflect the change of local electrical field close to each carotenoid molecule which exists as a minor pool on the light-harvesting pigment-protein complex II (LHC II). Absorbance changes of carotenoid and chlorophylls were also induced by tetraphenylborate in membranes of spinach chloroplasts.  相似文献   

13.
The interaction between copper (II) 2-oxo-propionic acid salicyloyl hydrazone (CuIIL) and bovine serum albumin (BSA) under physiological conditions was investigated by the methods of fluorescence spectroscopy, UV-Vis absorption, and circular dichroism spectroscopy. Fluorescence data showed that the fluorescence quenching of BSA by CuIIL was the result of the formation of the BSA–CuIIL complex. The apparent binding constants (K a) between CuIIL and BSA at four different temperatures were obtained according to the modified Stern–Volmer equation. The thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS), for the reaction were calculated to be ?80.79 kJ mol?1 and ?175.48 J mol?1 K?1 according to van’t Hoff equation. The results indicated that van der Waals force and hydrogen bonds were the dominant intermolecular force in stabilizing the complex. The binding distance (r) between CuIIL and the tryptophan residue of BSA was obtained to be 4.1 nm according to Förster’s nonradioactive energy transfer theory. The conformational investigation showed that the application of CuIIL increased the hydrophobicity of amino acid residues and decreased the α-helical content of BSA (from 62.71% to 37.31%), which confirmed some microenvironmental and conformational changes of BSA molecules.  相似文献   

14.
15.
在IRIS Indigo2(SGI公司)工作站上,利用InsightⅡ/MSI软件包,以TAT三链DNA为模板,采用同源模建的方法,分别建立起两个含21nt的脱氧寡核苷酸CP1(G3TG2TGT2G5TG2TGT)和CP3(TGTG2TG5T2GTG2TG3)的三维结构.采用分子力学方法进行能量优化,将得到的能量最低结构作为分子的优势构象.研究结果显示,CP1的能量低于CP3的能量,即前者的结构较后者稳定.从而证明了CP1与乙肝病毒(HBV)的核心启动子(Cp)片段之间能稳定地形成三链DNA,并能特异性地抑制DNA结合蛋白与Cp片段的结合.这些结果表明,三链DNA的形成有可能抑制DNA的转录.  相似文献   

16.
Of the inhibitory checkpoints in the immune system, programmed death 1 (PD-1) is one of the most promising targets for cancer immunotherapy. The anti-PD-1 antibodies currently approved for clinical use or under development bind to human PD-1 (hPD-1), but not murine PD-1. To facilitate studies in murine models, we developed a functional antibody against both human and murine PD-1, and compared the epitopes of such antibody to a counterpart that only bound to hPD-1. To quickly identify the epitopes of the 2 antibodies, we used alanine scanning and mammalian cell expression cassette. The epitope identification was based on PD-1-binding ELISA and supported by affinity ranking of surface plasmon resonance results. The hPD-1 epitopes of the 2 functional antibodies were also compared with the binding region on hPD-1 that is responsible for PD-L1 interaction. In silico modeling were conducted to explain the different binding modes of the 2 antibodies, suggesting a potential mechanism of the antibody cross-species binding.  相似文献   

17.
Burkholderia cenocepacia is an opportunistic pathogen threatening patients with cystic fibrosis. Flagella are required for biofilm formation, as well as adhesion to and invasion of epithelial cells. Recognition of flagellin via the Toll-like receptor 5 (TLR5) contributes to exacerbate B. cenocepacia-induced lung epithelial inflammatory responses. In this study, we report that B. cenocepacia flagellin is glycosylated on at least 10 different sites with a single sugar, 4,6-dideoxy-4-(3-hydroxybutanoylamino)-d-glucose. We have identified key genes that are required for flagellin glycosylation, including a predicted glycosyltransferase gene that is linked to the flagellin biosynthesis cluster and a putative acetyltransferase gene located within the O-antigen lipopolysaccharide cluster. Another O-antigen cluster gene, rmlB, which is required for flagellin glycan and O-antigen biosynthesis, was essential for bacterial viability, uncovering a novel target against Burkholderia infections. Using glycosylated and nonglycosylated purified flagellin and a cell reporter system to assess TLR5-mediated responses, we also show that the presence of glycan in flagellin significantly impairs the inflammatory response of epithelial cells. We therefore suggest that flagellin glycosylation reduces recognition of flagellin by host TLR5, providing an evasive strategy to infecting bacteria.  相似文献   

18.
Striatin-interacting phosphatases and kinases (STRIPAKs) are evolutionarily conserved supramolecular complexes that control various important cellular processes such as signal transduction and development. However, the role of the STRIPAK complex in pathogenic fungi remains elusive. In this study, the components and function of the STRIPAK complex were investigated in Fusarium graminearum, an important plant-pathogenic fungus. The results obtained from bioinformatic analyses and the protein–protein interactome suggested that the fungal STRIPAK complex consisted of six proteins: Ham2, Ham3, Ham4, PP2Aa, Ppg1, and Mob3. Deletion mutations of individual components of the STRIPAK complex were created, and observed to cause a significant reduction in fungal vegetative growth and sexual development, and dramatically attenuae virulence, excluding the essential gene PP2Aa. Further results revealed that the STRIPAK complex interacted with the mitogen-activated protein kinase Mgv1, a key component in the cell wall integrity pathway, subsequently regulating the phosphorylation level and nuclear accumulation of Mgv1 to control the fungal stress response and virulence. Our results also suggested that the STRIPAK complex was interconnected with the target of rapamycin pathway through Tap42-PP2A cascade. Taken together, our findings revealed that the STRIPAK complex orchestrates cell wall integrity signalling to govern the fungal development and virulence of F. graminearum and highlighted the importance of the STRIPAK complex in fungal virulence.  相似文献   

19.
Various Ionic and molecular activities in the extraceUular environment are vital to plant cell physiological processes. A noninvasive microsensing system (NMS) based on either the scanning ion-selective electrode technique (SIET) or the scanning polarographlc electrode technique (SPET) is able to obtain information regarding the transportation of various Ions/molecules in Intact samples under normal physiological conditions. The two-probe simultaneous test system (2STS) Is an Integrated system composed of SIET, SPET, and a Xu-Kunkel sampling protocol. In the present study, 2STS was able to simultaneously measure fluxes of H^+ and O2 of the Uly (Lillum Iongiflorum Thunb. cv. Ace) pollen tube while avoiding interference between the two probes. The results Indicate that the proton fluxes were effluxes, whereas the oxygen fluxes were Influxes, and they were closely correlated to each other surrounding the constitutive alkaline band region. Specifically, when the proton effluxes increased, the oxygen Influxes also increased. Therefore, the hypothesis of condensed active mitochondria existing in the alkalized area of the pollen tube proposed by Hepler's group is supported.  相似文献   

20.
Carbonic anhydrases (CA) inhibitory action could be linked to the treatment of a number of ailments, including cancer, osteoporosis, glaucoma, and several neurological problems. For the development of effective CA inhibitors, a variety of heterocyclic rings have been investigated. Furthermore, at high altitudes, oxygen pressure drops, resulting in the formation of reactive oxygen and nitrogen species, and CA inhibitors having role in combating this oxidative stress. Acetazolamide contains thiadiazole ring, which has aroused researchers’ interest because of its CA inhibitory action. In the present study, we used a number of drug design tools, such as pharmacophore modeling, 3D QSAR, docking, and virtual screening on twenty-seven 1,3,4-thiadiazole derivatives that have been described as potential CA inhibitors in the literature. An atom-based 3D-QSAR analysis was carried out to determine the contribution of individual atoms to model generation, while a pharmacophore mapping investigation was carried out to find the common unique pharmacophoric properties required for biological activity. The coefficient of determination for both the training and test sets were statistically significant in the generated model. The best QSAR model was chosen based on the values of R2 (0.8757) and Q2 (0.7888). A molecular docking study was also conducted against the most potent analogue 4m, which has the highest SP docking score (−5.217) (PDB ID: 6g3v). The virtual screening revealed a number of promising compounds. The screened compound ZINC77699643 interacted with the amino acid residues, Pro201 and Thr199, in the virtual screening study (PDB ID: 6g3v). These interactions demonstrated the significance of the CA inhibitory activity of the compound. Furthermore, ADME study revealed useful information regarding compound’s drug-like properties. Therefore, the findings of the present investigation could aid in the development of more potent CA inhibitors, which could benefit the treatment of oxidative stress at high altitudes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号