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91.
Frederick Steiner Laurel McSherry Dean Brennan Mark Soden Joe Yarchin Douglas Green 《Journal of the American Planning Association. American Planning Association》2013,79(2):207-222
As part of ongoing cooperation between the City of Phoenix and Arizona State University, a charrette was organized. Planners, landscape architects, environmental scientists, and architects explored concepts for development within a 110-square-mile (285-km2) portion of Phoenix. The charrette was the summation of over a year of environment studies of the planning area. This part of northern Phoenix occupies a largely undeveloped upper Sonoran desert landscape experiencing intense development pressure. Four charrette teams addressed desert preservation, rural desert development, suburban desert development, and growth corridors. This article focuses on some of the strategies proposed by the suburban desert development team. One of these called for an alternative pattern of development aligned with natural drainage corridors. Several concepts from the charrette and findings from the environmental research were adopted by the City in the revised general plan for the area. 相似文献
92.
Dariush Nasrollahzadeh Gholamreza Roshandel Tiffany Myriam Delhomme Patrice Hodonou Avogbe Matthieu Foll Farrokh Saidi Hossein Poustchi Masoud Sotoudeh Reza Malekzadeh Paul Brennan James Mckay Pierre Hainaut Behnoush Abedi-Ardekani 《International journal of molecular sciences》2021,22(11)
Circulating cell-free DNA (cfDNA) is emerging as a potential tumor biomarker. CfDNA-based biomarkers may be applicable in tumors without an available non-invasive screening method among at-risk populations. Esophageal squamous cell carcinoma (ESCC) and residents of the Asian cancer belt are examples of those malignancies and populations. Previous epidemiological studies using cfDNA have pointed to the need for high volumes of good quality plasma (i.e., >1 mL plasma with 0 or 1 cycles of freeze-thaw) rather than archival serum, which is often the main available source of cfDNA in retrospective studies. Here, we have investigated the concordance of TP53 mutations in tumor tissue and cfDNA extracted from archival serum left-over from 42 cases and 39 matched controls (age, gender, residence) in a high-risk area of Northern Iran (Golestan). Deep sequencing of TP53 coding regions was complemented with a specialized variant caller (Needlestack). Overall, 23% to 31% of mutations were concordantly detected in tumor and serum cfDNA (based on two false discovery rate thresholds). Concordance was positively correlated with high cfDNA concentration, smoking history (p-value = 0.02) and mutations with a high potential of neoantigen formation (OR; 95%CI = 1.9 (1.11–3.29)), suggesting that tumor DNA release in the bloodstream might reflect the effects of immune and inflammatory context on tumor cell turnover. We identified TP53 mutations in five controls, one of whom was subsequently diagnosed with ESCC. Overall, the results showed that cfDNA mutations can be reliably identified by deep sequencing of archival serum, with a rate of success comparable to plasma. Nonetheless, 70% non-identifiable mutations among cancer patients and 12% mutation detection in controls are the main challenges in applying cfDNA to detect tumor-related variants when blindly targeting whole coding regions of the TP53 gene in ESCC. 相似文献
93.
A statistical algorithm has been developed to compensate for the fixed-pattern noise associated with spatial nonuniformity and temporal drift in the response of focal-plane array infrared imaging systems. The algorithm uses initial scene data to generate initial estimates of the gain, the offset, and the variance of the additive electronic noise of each detector element. The algorithm then updates these parameters by use of subsequent frames and uses the updated parameters to restore the true image by use of a least-mean-square error finite-impulse-response filter. The algorithm is applied to infrared data, and the restored images compare favorably with those restored by use of a multiple-point calibration technique. 相似文献
94.
Markys G. Cain Rebecca L. Cain Michael H. Lewis John Gent 《Journal of the American Ceramic Society》1997,80(7):1873-1876
A novel in situ reaction between a ceria-doped zirconia interphase coating on Saphikon fibers and an outer alumina coating has resulted in the formation of oriented hexaaluminate platelets which can act as a low fracture energy interface barrier for crack deflection in oxide-oxide ceramic-matrix composites (CMCs). The reaction proceeds only in reducing environments where the reduction of the cerium and zirconium ions to their 3+ valent state causes a destabilization phenomenon consistent with previously reported findings. The diffusion of the cerium from the zirconia into solid solution with the alumina can stabilize the layered hexaaluminate structure. Preferred orientational growth of the hexaaluminate parallel to the coating interface was observed which is the required orientation for enhanced debonding at the fiber/matrix interface in long-fiber-reinforced CMCs. 相似文献
95.
Nonspatial pretraining (NSP) enables rats to learn the general strategies of the water maze task (WMIs; e.g., learning to swim away from the wall and to climb onto the hidden platform), reduces sensorimotor disturbances, and eliminates acquisition impairments caused by scopolamine hydrobromide, a muscarinic antagonist. To evaluate the contributions of the components of NSP to these effects, NSP was fractionated so that different groups of male rats swam, were placed onto the hidden platform, climbed onto the hidden platform, or were placed into an empty maze before spatial training under scopolamine. No single component of the NSP procedure was sufficient to produce its full effects on sensorimotor disturbances and WMT acquisition. Experience with most or perhaps all of the specific behaviors required in the WMT appears to be important for NSP to produce its full effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
97.
AD Foey SL Parry LM Williams M Feldmann BM Foxwell FM Brennan 《Canadian Metallurgical Quarterly》1998,160(2):920-928
IL-10 is an anti-inflammatory cytokine with potent immunomodulatory effects, including inhibition of cytokine production. However, regulation of monocyte IL-10 production is poorly understood. In this report we have investigated the mechanisms of LPS-induced IL-10 production by human peripheral blood monocytes and demonstrate that IL-10 synthesis is uniquely dependent on the endogenous proinflammatory cytokines IL-1 and/or TNF-alpha. LPS signal transduction in monocytes has been shown to involve activation of the p38 and p42 mitogen-activated protein kinase (MAPK) cascades. The results in this paper indicate that inhibition of p38 MAPK potently inhibited the production of IL-10, IL-1beta, and TNF-alpha, whereas blockade of the p42/44 MAPK pathway, while partially inhibiting TNF-alpha and IL-1beta production, had no effect on monocyte secretion of IL-10. Furthermore, neither the inhibition of monocyte TNF-alpha induced by IL-10 nor the stimulation of soluble TNF receptor production was affected by inhibition of the p42/44 MAPK pathway, suggesting that this signaling event is not involved in either monocyte production of or anti-inflammatory responses to IL-10. These data raise the interesting possibility that proinflammatory TNF-alpha-mediated effects may be selectively blocked without modulating the induction or the response to IL-10, whereas the signaling events associated with the anti-inflammatory events induced by IL-10 remain to be elucidated. 相似文献
98.
R Murali PJ Brennan T Kieber-Emmons MI Greene 《Canadian Metallurgical Quarterly》1996,93(13):6252-6257
The epidermal growth factor receptor (EGFR) and p185c-neu proteins associate as dimers to create an efficient signaling assembly. Overexpression of these receptors together enhances their intrinsic kinase activity and concomitantly results in oncogenic cellular transformation. The ectodomain is able to stabilize the dimer, whereas the kinase domain mediates biological activity. Here we analyze potential interactions of the cytoplasmic kinase domains of the EGFR and p185c-neu tyrosine kinases by homology molecular modeling. This analysis indicates that kinase domains can associate as dimers and, based on intermolecular interaction calculations, that heterodimer formation is favored over homodimers. The study also predicts that the self-autophosphorylation sites located within the kinase domains are not likely to interfere with tyrosine kinase activity, but may regulate the selection of substrates, thereby modulating signal transduction. In addition, the models suggest that the kinase domains of EGFR and p185c-neu can undergo higher order aggregation such as the formation of tetramers. Formation of tetrameric complexes may explain some of the experimentally observed features of their ligand affinity and hetero-receptor internalization. 相似文献
99.
The Escherichia coli purine repressor, PurR, exists in an equilibrium between open and closed conformations. Binding of a corepressor, hypoxanthine or guanine, shifts the allosteric equilibrium in favor of the closed conformation and increases the operator DNA binding affinity by 40-fold compared to aporepressor. Glu70 and Trp147 PurR mutations were isolated which perturb the allosteric equilibrium. Three lines of evidence indicate that the allosteric equilibrium of E70A and W147A aporepressors was shifted toward the closed conformation. First, compared to wild-type PurR, these mutant repressors had a 10-30-fold higher corepressor binding affinity. Second, the mutant aporepressors bound to operator DNA with an affinity that is characteristic of the wild-type PurR holorepressor. Third, binding of guanine to wild-type PurR resulted in a near-UV circular dichroism spectral change at 297-305 nm that is attributed to the closed conformation. The circular dichroism spectrum of the E70A aporepressor at 297-305 nm was that expected for the closed conformation, and it was not appreciably altered by corepressor binding. Mutational analysis was used to identify an Arg115-Ser46' interdomain intersubunit hydrogen bond that is necessary for transmitting the allosteric transition in the corepressor binding domain to the DNA binding domain. R115A and S46G PurR mutants were defective in DNA binding in vitro and repressor function in vivo although corepressor binding was identical to the wild type. These results establish that the hydrogen bond between the side chain NH2 of Arg115 and the main chain CO of Ser46' plays a critical role in interdomain signaling. 相似文献
100.
JL Cain 《Canadian Metallurgical Quarterly》1998,28(2):395-410
Sinusoidal cells in the rat liver were studied in vivo and in vitro using the original vital staining with lithium carmine, which has contributed much to the development of the concept of the reticulo-endothelial system. Immunohistochemical and electron-microscopic studies revealed that the dye-incorporating cells were sinusoidal endothelial cells, Kupffer cells, and monocytes. The endothelial cells took up much more dye than did the Kupffer cells and bulged largely into the sinusoidal lumen. Electron microscopy revealed that small particles of lithium carmine were associated with coated vesicles of endothelial cells and ruffled membranes of Kupffer cells. In the endothelial cells, these particles were present in various concentrations within vacuolated structures and condensed in the lysosomes forming large aggregates of lithium carmine lumps. These lumps showed crystalline structures, within which the size of the individual particle was up to 30 nm in width and 50 nm in length. A few endothelial cells containing abundant dye underwent degeneration, and some were taken up by Kupffer cells. Liver endothelial cells isolated from lithium carmine-administered rats endocytosed fluorescence-labeled collagen. Isolated endothelial cells from normal rat liver, when cultured with lithium carmine, did not take up any dye, and their endocytosis of formaldehyde-treated albumin was inhibited dose-dependently. We conclude that in the liver, endothelial cells, but not Kupffer cells, predominantly take up lithium carmine. Furthermore, we propose the existence of a generalized cell system based on its vital staining capacity. 相似文献