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排序方式: 共有737条查询结果,搜索用时 13 毫秒
21.
Marian J. Patrick 《国际水》2013,38(1):63-80
Managing for social and environmental justice in water allocation is a necessary yet challenging goal. Often, what can appear as a just or equitable outcome for a specific location or group of stakeholders can also result in injustices at other locations or for other stakeholders. This paper describes a conceptual framework, The Cycles and Spirals of Justice, that helps make sense of the relationship between justice and injustice in the context of water-allocation decision making by explicitly utilizing a landscape-ecology understanding of scale and levels. The framework is illustrated using a case study from the Murray-Darling Basin in Australia and describes how justice and injustice are part of a cycling continuum of “justice for whom” and how this plays out in a multi-level system where the problem of scale can surface. 相似文献
22.
J. Marian B. D. Wirth G. R. Odette J. M. Perlado 《Computational Materials Science》2004,31(3-4):347-367
The nucleation and growth of radiation-induced Cu-rich clusters have proved an important topic in the study of microstructural and chemical evolution responsible for property changes in pressure vessel steels subjected to neutron irradiation. Small Cu clusters can act as precipitate precursors and contribute to the hardening of the material by impeding dislocation glide. Reliable Cu diffusion coefficients provide critical input to Monte Carlo and rate theory approaches to study the kinetics of diffusion and clustering that lead to the formation of such Cu-rich features. In this paper we report the results of a molecular dynamics study of Cu solute-atom diffusion in a Fe–0.9at%Cu alloy, using high-temperatures and high-vacancy concentrations to hasten the convergence of the calculation. We find a value of 0.61 eV for the migration energy of Cu in the b.c.c Fe matrix, in good agreement with available experimental results. The main diffusion mechanisms under the conditions simulated are identified and discussed, and the effect of vacancy and solute clustering on Cu migration is assessed. In addition, a rigorous computation of the solute enhancement factor, correlation factor and solute diffusivity is performed within the five-frequency theoretical framework and the harmonic approximation. The results obtained are compared with those yielded by the direct MD simulations and the observed differences discussed. 相似文献
23.
We propose an alternative approach to generate languages by means of P systems: building up an appropriate representation
for a string by means of a corresponding membrane structure and then generating the string by visiting the membrane structure
according to a well-specified strategy. To this aim, we consider P systems with active membranes, allowing membrane creation
or division or duplication and dissolution, where the output of a computation may be obtained either by visiting the tree
associated with the membrane structure, or by following the traces of a specific object, called traveller, or sending out
the objects. For each of these approaches, we provide characterizations of recursively enumerable languages based on P systems
that use different sets of operations for modifying the membrane structure.
Francesco Bernardini: He started his Ph.D. at the University of Sheffield in December 2002 after having previously got a master degree in Computer
Science from the University of Pisa in Italy. His research is dedicated to the study of theoretical aspects of membrane computing
(P systems) and discrete models of biological systems based on P systems.
Marian Gheorghe, Ph.D.: His main research interests are in computational models and their applications to software modelling and testing, formal
specifications of agent based systems, software engineering. He was investigating computational power of various generative
devices (regular, context-free, fully initial; grammar systems; L-systems and variants). He is currently interested in natural
computing (membrane calculus) and biological modelling. 相似文献
24.
This paper examines the current state of project cultures in the German turnkey construction industry and the ideal project cultures in terms of partnering from the perspective of various key stakeholders (i.e., Investors, General Contractors, (Sub-)Contractors and Designers). To investigate the current and ideal cultures, data were gathered among the key stakeholders by means of a survey study with 72 respondents divided over 12 companies. The respondents rated the current and desired cultures by using the Organizational Culture Assessment Instrument, which belongs to the Competing Values Framework. The investigations show many similarities and differences between the stakeholder perspectives of the current and the idealized partnering project cultures. Mainly, the General Contractors desire more cooperative behaviors than the (Sub-)Contractors, and the Investors desire more pronounced flexibility than the General Contractors. All stakeholders desire a cultural change from highly competitive behaviors toward more cooperation. Changes in terms of clear procedures or more flexibility are only desired by the Designers. Defining both the current and an ideal partnering project culture enables academics and project managers to compare their actual project cultures to an ideal situation. With such an approach, academics and project managers could measure whether new tools or changes in resources affect their project cultures toward a partnering project culture. 相似文献
25.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
26.
Vlasta Demeckova Dagmar Mudronova Sona Gancarcikova Peter Kubatka Karol Kajo Monika Kassayova Bianka Bojkova Marian Adamkov Peter Solr 《International journal of molecular sciences》2022,23(12)
Due to the physiological complexity of the tumour, a single drug therapeutic strategy may not be sufficient for effective treatment. Emerging evidence suggests that combination strategies may be important to achieve more efficient tumour responses. Different immunomodulators are frequently tested to reverse the situation for the purpose of improving immune response and minimizing chemotherapy side effects. Immodin (IM) represents an attractive alternative to complement chemotherapy, which can be used to enhance the immune system after disturbances resulting from the side effects of chemotherapy. In the presented study, a model of CT26 tumor-bearing mice was used to investigate the effect of single IM or its combination with 5-fluorouracil (5-FU) on colon cancer cells. Our results highlight that the beneficial role of IM claimed in previous studies cannot be generalised to all chemotherapeutic drugs, as 5-FU toxicity was not increased. On the contrary, the chemotherapeutic anti-cancer efficacy of 5-FU was greatly compromised when combined with IM. Indeed, the combined treatment was significantly less effective regarding the tumour growth and animal survival, most probably due to the increased number of tumour-associated macrophages, and increased 5-FU cytotoxic effect related to kidneys and the liver. 相似文献
27.
28.
Jirina Tyleckova Rita Hrabakova Katerina Mairychova Petr Halada Lenka Radova Petr Dzubak Marian Hajduch Suresh J. Gadher Hana Kovarova 《International journal of molecular sciences》2012,13(12):15536-15564
A comprehensive proteome map of T-lymphoblastic leukemia cells and its alterations after daunorubicin, doxorubicin and mitoxantrone treatments was monitored and evaluated either by paired comparison with relevant untreated control and using multivariate classification of treated and untreated samples. With the main focus on early time intervals when the influence of apoptosis is minimized, we found significantly different levels of proteins, which corresponded to 1%–2% of the total amount of protein spots detected. According to Gene Ontology classification of biological processes, the highest representation of identified proteins for all three drugs belong to metabolic processes of proteins and nucleic acids and cellular processes, mainly cytoskeleton organisation and ubiquitin-proteasome pathway. Importantly, we observed significant proportion of changes in proteins involved in the generation of precursor metabolites and energy typical for daunorubicin, transport proteins participating in response to doxorubicin and a group of proteins of immune system characterising response to mitoxantrone. Both a paired comparison and the multivariate evaluation of quantitative data revealed daunorubicin as a distinct member of the group of anthracycline/anthracenedione drugs. A combination of identified drug specific protein changes, which may help to explain anti-cancer activity, together with the benefit of blocking activation of adaptive cancer pathways, presents important approaches to improving treatment outcomes in cancer. 相似文献
29.
Ewa Watorek Tomasz Golebiowski Mariusz Kusztal Krzysztof Letachowicz Waldemar Letachowicz Hanna Augustyniak Bartosik Jerzy Garcarek Katarzyna Madziarska Wacław Weyde Marian Klinger 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):113-117
Elderly patients, defined as octogenarians and nonagenarians, are an increasing population entering renal replacement therapy. Advanced age appears as an exclusive factor negatively influencing dialysis practice. Elderly patients are referred late for the initiation of hemodialysis and more likely are offered catheters rather than arteriovenous fistulae (AVF), which increase mortality and negatively affect quality of life. We present our approach to the creation of vascular access for hemodialysis in this demanding population. In 2006–2012, 39 patients aged 85.9 ± 2.05 with end‐stage renal disease, mainly resulting from ischemic nephropathy, were admitted to the Department of Nephrology to establish permanent vascular access for hemodialysis: preferably AVF. Temporary dialysis catheters were implanted in uremic emergency to bridge the time to fistula creation/maturation. AVF was attempted in 87.2% of the patients. Primary AVF function was achieved in 54% of the patients. Cumulative proportional survival of AVF at months 12 and 24 was 81.5%. Ninety‐four percent of AVF were localized on the forearm: 74% in the distal and 20% in the proximal part. Mean duration of hemodialysis therapy was 20.80 ± 19.45 months. The mean time of AVF use was 15.9 ± 20.2 months. Until present, 38% have been dialyzed using AVF for 31.0 ± 18.8 months. Five patients died with functioning fistula. Eight patients initiated hemodialysis therapy with fistula. During further observation, the use of AVF increased to 62%. Elderly patients should not be denied creation of AVF as a rule. The outcome of AVF benefits more from acknowledging individual vascular conditions rather than age of the patient. 相似文献
30.
Mihail Elisa Lucica Boroica Bogdan Alexandru Sava Stefan Marian Iordache Ana-Maria Iordache Ileana Cristina Vasiliu Raluca Constantina Stefan Aurelian Catalin Galca Victor Kuncser Mihai Eftimie 《Journal of the American Ceramic Society》2020,103(7):3978-3990
This work is focused on investigation of thermal, structural, optical, magnetic, and magneto-optical properties of novel titanium phosphate-tellurite glass applied as Faraday rotators. The glass belonging to the system 35Li2O–10Al2O3–5TiO2–45P2O5–5TeO2 was prepared by a nonconventional wet route of raw materials processing, followed by melting-quenching-annealing steps. Some important physical properties of the investigated glass have been measured and calculated, providing knowledge related to glass compactness, electronic structure, glass forming capability, etc. XRD analysis evidenced an amorphous network structure of the investigated glass. The optical absorption in the Vis domain is mainly due to Ti3+ ions and Te2 clusters formed during the glass melting process. A relatively low optical absorption is noticed over 600 nm that activates a significant Faraday magneto-optical effect. Photoluminescence bands in the blue, red, and infrared domains are observed, caused by Te2 clusters formed during the glass melting process. The magnetization in dependency on applied magnetic field reveals a complex behavior of the glass, depending on temperature. Thus, it is found a ferromagnetic behavior up to 2000 Oe, a paramagnetic component up to 40 000 Oe, followed by a diamagnetic one over 40 000 Oe. Faraday rotation angle and Verdet constant values in the visible domain are correlated with the reduced TeO2 content of the glass. 相似文献