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991.
Bhanu Vardhan Reddy Kuncharam Benjamin A. Wilhite 《American Institute of Chemical Engineers》2013,59(11):4334-4345
The novel application of a catalytic water‐gas‐shift membrane reactor for selective removal of CO from H2‐rich reformate mixtures for achieving gas purification solely via manipulation of reaction and diffusion phenomena, assuming Knudsen diffusion regime and the absence of hydrogen permselective materials, is described. An isothermal, two‐dimensional model is developed to describe a tube‐and‐shell membrane reactor supplied with a typical reformate mixture (9% CO, 3% CO2, 28% H2, and 15% H2O) to the retentate volume and steam supplied to the permeate volume such that the overall H2O:CO ratio within the system is 9:1. Simulations indicate that apparent CO:H2 selectivities of 90:1 to >200:1 at H2 recoveries of 20% to upwards of 40% may be achieved through appropriate design of the catalytic membrane and selection of operating conditions. Under these conditions, simulations predict an apparent hydrogen permeability of 2.3 × 10?10 mol m?1 Pa, which compares favorably against that of competing hydrogen‐permselective membranes. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4334–4345, 2013 相似文献
992.
Patricia Cid María Jesús Doldán María Soledad Rodríguez Benjamin Prego Encarnación de Miguel 《Microscopy research and technique》2013,76(6):588-597
The morphogenesis and cell proliferation in the retina of turbot (Psetta maxima, Pleuronectiformes: Teleostei) from embryo through metamorphosis have been examined by using proliferating cell nuclear antigen (PCNA)‐immunohistochemistry and general histological procedures. In the embryonic retina, cell proliferation and spatial cell reorganization form the anlage of the pigment epithelium and neural retina. Neurogenesis begins around hatching in the temporal retina, dorsal to the optic nerve exit, and then a wave of cell differentiation spreads to the nasal retina to yield a laminated retina by the end of the prolarval turbot stage. Germinal zones in the differentiated retina persist as a rim at the retinal margin, as well as surrounding the optic fissure in premetamorphic and metamorphic turbot larvae. In these zones, progenitor cells with different morphologies show a similar spatial arrangement, which suggests that they have a similar retinogenic potential. During metamorphosis, asymmetric proliferative activity in turbot germinal zones is associated with a marked expansion of the retinal tissue. Scattered stem cells in the laminated retina, related to the lineage of rod photoreceptors, were also observed both in large premetamorphic larvae and metamorphic turbots. The proliferative activity of these cells increases considerably during metamorphosis, when rod photoreceptors become morphologically differentiated. Microsc. Res. Tech. 76:588–597, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
993.
A review of power electronics interfaces for distributed energy systems towards achieving low-cost modular design 总被引:1,自引:0,他引:1
Sudipta Chakraborty Bill Kramer Benjamin Kroposki 《Renewable & Sustainable Energy Reviews》2009,13(9):2323-2335
Due to increased attention towards clean and sustainable energy, distributed energy (DE) systems are gaining popularity all over the world. Power electronics are an integral part of these energy systems being able to convert generated electricity into consumer usable and utility compatible forms. But the addition of power electronics adds costs to the DE capital investments along with some reliability issues. Therefore, widespread use of distributed energy requires power electronics topologies that are less expensive and more dependable. Use of modular power electronics is a way to address these issues. Adoption of functional building blocks that can be used for multiple applications results in high volume production and reduced engineering effort, design testing, onsite installation and maintenance work for specific customer applications. In this paper, different power electronics topologies are reviewed that are typically used with distributed energy systems. The integrated power electronics module (IPEM) based back-to-back converter topologies are found to be most suitable interface that can operate with different DE systems with small or no modifications. Also the requirements for a hierarchical control structure with standardized power and communication interfaces are addressed in the paper along with some discussion on future design possibilities for the IPEM-based power electronics topologies. It is expected that modular and flexible power electronics and standardized controls and interfaces, will provide commonality in hardware and software for the power electronics interfaces, thus will enable their volume production and decrease their cost share in distributed energy applications. 相似文献
994.
Christine H. Moran Sean M. Wainerdi Tonya K. Cherukuri Carter Kittrell Benjamin J. Wiley Nolan W. Nicholas Steven A. Curley John S. Kanzius Paul Cherukuri 《Nano Research》2009,2(5):400-405
Capacitively coupled shortwave radiofrequency fields (13.56 MHz) resistively heat low concentrations (∼1 ppm) of gold nanoparticles
with a thermal power dissipation of ∼380 kW/g of gold. Smaller diameter gold nanoparticles (< 50 nm) heat at nearly twice
the rate of larger diameter gold nanoparticles (≥50 nm), which is attributed to the higher resistivity of smaller gold nanostructures.
A Joule heating model has been developed to explain this phenomenon and provides critical insights into the rational design
and engineering of nanoscale materials for noninvasive thermal therapy of cancer.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.
These two authors made an equal contribution to the work. 相似文献
995.
Van Hulle Carol A.; Waldman Irwin D.; D’Onofrio Brian M.; Rodgers Joseph Lee; Rathouz Paul J.; Lahey Benjamin B. 《Canadian Metallurgical Quarterly》2009,118(4):711
It is necessary to determine if causal influences on developing antisocial behavior change with age to guide both research and theory on its origins. The extent to which the same genetic factors influence antisocial behavior across 4–17 years of age was estimated using 2,482 sibling pairs of varying genetic relatedness. Assessments of antisocial behavior by mothers (4–9 years), mothers and youth (10–13 years), and youth (14–17 years) reflected the changing validity of informants across development. Genetic influences on antisocial behavior at 14–17 years were entirely shared with those on antisocial behavior at 10–13 years according to both informants. Genetic influences on antisocial behavior at 14–17 years were distinct from those at 4–9 years, however. These age differences in genetic influences cannot be fully distinguished from informant differences across age, but the present findings indicate that youth reported to be persistently antisocial during childhood and adolescence are influenced by one set of genetic factors influencing parent-report conduct problems in childhood and a second set of genetic influences on youth-reported delinquency that come into play around the time of the pubertal transition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
This paper uses a static computational game theoretic model of a fully opened European electricity market and can take strategic interaction among electricity-producing firms into account. The model is run for a number of scenarios: first, in the baseline under perfect competition, the prices differ due to the presence of various generation technologies and a limited ability to exchange electricity among countries. In addition, when large firms exercise market power, the model runs indicate that prices are the highest in countries where the number of firms is low. Second, dry weather would increase the prices in the hydro-rich Nordic countries followed by the Alpine countries. The price response would be about 20% higher with market power. Third, more transmission capacity would lower the prices in countries with high prices and it also reduces the impact of market power. Hence, more transmission capacity can improve market competitiveness. 相似文献
997.
Francesco Ciabuschi Oscar Martín Martín Benjamin Ståhl 《Management International Review》2010,50(4):471-491
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This paper investigates headquarters’ value-adding role in knowledge transfer. Transfer performance is considered in terms
of both efficiency and effectiveness, and a model that includes headquarters’ distribution of decision-making rights, resource
allocation, and direct intervention is tested on 141 innovation transfer projects. 相似文献
998.
999.
David W. Freeman Elisa Rodrigues Sousa Sofia Karkampouna Eugenio Zoni Peter C. Gray David S. Salomon Marianna Kruithof-de Julio Benjamin T. Spike 《International journal of molecular sciences》2021,22(18)
There exists a set of factors termed oncofetal proteins that play key roles in ontogeny before they decline or disappear as the organism’s tissues achieve homeostasis, only to then re-emerge in cancer. Although the unique therapeutic potential presented by such factors has been recognized for more than a century, their clinical utility has yet to be fully realized1. This review highlights the small signaling protein CRIPTO encoded by the tumor derived growth factor 1 (TDGF1/Tdgf1) gene, an oft cited oncofetal protein whose presence in the cancer literature as a tumor promoter, diagnostic marker and viable therapeutic target continues to grow. We touch lightly on features well established and well-reviewed since its discovery more than 30 years ago, including CRIPTO’s early developmental roles and modulation of SMAD2/3 activation by a selected set of transforming growth factor β (TGF-β) family ligands. We predominantly focus instead on more recent and less well understood additions to the CRIPTO signaling repertoire, on its potential upstream regulators and on new conceptual ground for understanding its mode of action in the multicellular and often stressful contexts of neoplastic transformation and progression. We ask whence it re-emerges in cancer and where it ‘hides’ between the time of its fetal activity and its oncogenic reemergence. In this regard, we examine CRIPTO’s restriction to rare cells in the adult, its potential for paracrine crosstalk, and its emerging role in inflammation and tissue regeneration—roles it may reprise in tumorigenesis, acting on subsets of tumor cells to foster cancer initiation and progression. We also consider critical gaps in knowledge and resources that stand between the recent, exciting momentum in the CRIPTO field and highly actionable CRIPTO manipulation for cancer therapy and beyond. 相似文献
1000.
Robin C. Su Joshua D. Breidenbach Khaled Alganem Fatimah K. Khalaf Benjamin W. French Prabhatchandra Dube Deepak Malhotra Robert McCullumsmith John B. Presloid R. Mark Wooten David J. Kennedy Steven T. Haller 《International journal of molecular sciences》2021,22(18)
We were the first to previously report that microcystin-LR (MC-LR) has limited effects within the colons of healthy mice but has toxic effects within colons of mice with pre-existing inflammatory bowel disease. In the current investigation, we aimed to elucidate the mechanism by which MC-LR exacerbates colitis and to identify effective therapeutic targets. Through our current investigation, we report that there is a significantly greater recruitment of macrophages into colonic tissue with pre-existing colitis in the presence of MC-LR than in the absence of MC-LR. This is seen quantitatively through IHC staining and the enumeration of F4/80-positive macrophages and through gene expression analysis for Cd68, Cd11b, and Cd163. Exposure of isolated macrophages to MC-LR was found to directly upregulate macrophage activation markers Tnf and Il1b. Through a high-throughput, unbiased kinase activity profiling strategy, MC-LR-induced phosphorylation events were compared with potential inhibitors, and doramapimod was found to effectively prevent MC-LR-induced inflammatory responses in macrophages. 相似文献
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