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71.
We demonstrate a technique for purification of nucleic acids from malaria parasites infecting human erythrocytes using isotachophoresis (ITP). We release nucleic acids from malaria-infected erythrocytes by lysing with heat and proteinase K for 10 min and immediately, thereafter, load sample onto a capillary device. We study the effect of temperature on lysis efficiency. We also implement pressure-driven counterflow during ITP extraction to extend focusing time and increase nucleic acid yield. We show that the purified genomic DNA samples are compatible with polymerase chain reaction (PCR) and demonstrate a clinically relevant limit of detection of 0.5 parasites per nanoliter using quantitative PCR. 相似文献
72.
Exline Julie J.; Park Crystal L.; Smyth Joshua M.; Carey Michael P. 《Canadian Metallurgical Quarterly》2011,100(1):129
Many people see themselves as being in a relationship with God and see this bond as comforting. Yet, perceived relationships with God also carry the potential for experiencing anger toward God, as shown here in studies with the U.S. population (Study 1), undergraduates (Studies 2 and 3), bereaved individuals (Study 4), and cancer survivors (Study 5). These studies addressed 3 fundamental issues regarding anger toward God: perceptions and attributions that predict anger toward God, its prevalence, and its associations with adjustment. Social-cognitive predictors of anger toward God paralleled predictors of interpersonal anger and included holding God responsible for severe harm, attributions of cruelty, difficulty finding meaning, and seeing oneself as a victim. Anger toward God was frequently reported in response to negative events, although positive feelings predominated. Anger and positive feelings toward God showed moderate negative associations. Religiosity and age correlated negatively with anger toward God. Reports of anger toward God were slightly lower among Protestants and African Americans in comparison with other groups (Study 1). Some atheists and agnostics reported anger involving God, particularly on measures emphasizing past experiences (Study 2) and images of a hypothetical God (Study 3). Anger toward God was associated with poorer adjustment to bereavement (Study 4) and cancer (Study 5), particularly when anger remained unresolved over a 1-year period (Study 5). Taken together, these studies suggest that anger toward God is an important dimension of religious and spiritual experience, one that is measurable, widespread, and related to adjustment across various contexts and populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Shaojie Fang ) Zhiyong Pang ) Fenggong Wang ) Liang Lin ) Shenghao Han ) ) School of Physics State Key Laboratory of Crystal Materials Sh ong University Jinan China ) School of Space Science Applied Physics Sh ong University at Weihai Weihai China 《材料科学技术学报》2011,(3):223-226
The manganite La0.67Sr0.33MnO3(LSMO) thin films were grown on glass substrates in a mixed argon and oxygen atmosphere by using RF magnetron sputtering.The structural characteristics,transport behaviors and magnetic properties of LSMO films were studied by annealing the films in air at 550 and 620 ℃.The out-of-plane lattice parameter a LSMO contracted after annealing and was close to that of bulk LSMO abulk,indicating that the internal strain was fully relaxed.Nanocrystalline grains were observed in the annealed films.Enhanced saturation magnetization and metal-to-insulator transition temperature(TMI=268 K) were also obtained.Curie temperatures(Tc) of the as-grown films was 340 K with the same as that of annealed at 550 ℃,but dropped to 315 K when the annealing temperature increased to 620 ℃,which can be attributed to the oxygen release during annealing in atmosphere. 相似文献
74.
ABSTRACTQuestions about how to plan and govern for future urban mobility are reaching a critical point as Australian cities are faced with disruption to transport and urban systems arising from new forms of shared mobility services and the rise of autonomous vehicles. An industry engagement workshop, drawing on the insights of participants from public and private sectors of the industry, articulated a large array of complex and interrelated questions highlighting the uncertainty and scarcity of knowledge. These questions are grouped into three key themes concerning how implementation may take place, what the impacts of the uptake of these emerging transport technologies may be and how to understand them. The resultant research agenda is vast and one of multi-complexity by space, time and institutionally. 相似文献
75.
76.
BM Frey S Rafii M Teterson D Eaton RG Crystal MA Moore 《Canadian Metallurgical Quarterly》1998,160(2):691-699
Thrombopoietin (TPO) cDNA can be effectively delivered in vivo by adenovectors. Immune normal mice (BALB/c) and syngeneic mice with variable degrees of immune dysfunction nu, SCID, and NOD-SCID) were treated with an adenovirus vector expressing the human TPO cDNA (AdTPO). Platelet peaks were significantly higher in SCID and NOD-SCID mice compared with BALB/c and nu mice. Human plasma TPO concentration correlated with the platelet counts. SCID and NOD-SCID mice exhibited also granulocytosis and increased numbers of hemopoietic progenitors in bone marrow. Following platelet peak, BALB/c mice developed autoantibodies against murine TPO leading to thrombocytopenia and depletion of megakaryocytes and hemopoietic progenitors in bone marrow. AdTPO-treated SCID mice developed osteomyelofibrosis and extramedullary/extrasplenal hemopoiesis. In contrast, NOD-SCID mice with a similar magnitude of TPO overexpression did not show fibrotic changes in bone marrow. We conclude, first, that a chronic high level of TPO overexpression stimulates megakaryocytopoiesis and myelopoiesis leading to thrombocytosis and granulocytosis. Second, increased megakaryocytopoiesis is not sufficient for development of secondary osteomyelofibrosis. The functionally deficient monocytes and macrophages of NOD-SCID mice probably prevented fibrotic marrow changes. Third, immune deficiency enhances expression of adenovirally mediated transgenes, and fourth, xenogeneic transgene delivered by adenovector to a host with normal immune functions may induce loss of immune tolerance and autoimmune phenomenon. 相似文献
77.
研究了掺铈钾钠铌酸锶钡 (Ce∶KNSBN)光折变光纤“扇”特性及两波耦合的基本特性。通过实验发现 ,当入射光的入射角为 8°左右时 ,“扇”最小 ,这与块状晶体有根本的不同。在信号光与抽运光的入射夹角 2θ小于 11°时 ,两波耦合增益随入射夹角的增大而增大 ,而当入射夹角大于 11°时 ,两波耦合增益随着入射夹角的增大而迅速减小。给出了在各个不同的入射夹角下 ,两波耦合增益中透射的信号光的时间特性曲线。两波耦合增益随信号 抽运比的增加而增加 ,在入射夹角为 8° ,信号 抽运比为 1∶10 0 0时 ,两波耦合增益达到了 77,比块状晶体相应条件下提高了 4倍。用两波耦合的理论公式对增益随信号 抽运比的实验数据进行了拟合 ,二者相符 相似文献
78.
Sears Christopher R.; Campbell Crystal R.; Lupker Stephen J. 《Canadian Metallurgical Quarterly》2006,32(4):1040
What is the effect of a word's higher frequency neighbors on its identification time? According to activation-based models of word identification (J. Grainger & A. M. Jacobs, 1996; J. L. McClelland & D. E. Rumelhart, 1981), words with higher frequency neighbors will be processed more slowly than words without higher frequency neighbors because of the lexical competition mechanism embodied in these models. Although a critical prediction of these models, this inhibitory neighborhood frequency effect has been elusive in studies that have used English stimuli. In the present experiments, the effect of higher frequency neighbors was examined in the lexical decision task and when participants were reading sentences while their eye movements were monitored. Results suggest that higher frequency neighbors have little, if any, effect on the identification of English words. The implications for activation-based models of word identification are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
79.
Chemical mechanical polishing (CMP) was used to etch various GaN materials, such as GaN layers on sapphire and silicon carbide substrates grown by metal-organic chemical vapor deposition and thick GaN layers grown by physical vapor transport. It was found that CMP could reveal the dislocations in GaN surfaces due to a selective etching component. After the optimization of CMP condition, the surface finish improved and the subsurface damage was almost completely removed, demonstrated by atomic force microsco... 相似文献
80.
PL Leopold B Ferris I Grinberg S Worgall NR Hackett RG Crystal 《Canadian Metallurgical Quarterly》1998,9(3):367-378
T cells specific for nucleosomal autoepitopes are selectively expanded in lupus mice and these Th cells drive autoimmune B cells to produce pathogenic antinuclear antibodies. We transfected the TCR-alpha and -beta chain genes of a representative, pathogenic autoantibody-inducing Th clone specific for the nucleosomal core histone peptide H471-94 into TCR-negative recipient cells. Although the autoimmune TCRs were originally derived from SNF1 (I-Ad/q) mice, the transfectants could recognize the nucleosomal autoepitope presented by APC-bearing I-A molecules of all haplotypes tested, as well as human DR molecules. Competition assays indicated that the autoepitopes bound to the MHC class II groove. Most remarkably, MHC-unrestricted recognition of the nucleosomal peptide epitope was conferred by the lupus TCR-alpha chain even when it paired with a TCR-beta chain of irrelevant specificity. Several other disease-relevant Th clones and splenic T cells of lupus mice had similar properties. The TCR-alpha chains of these murine lupus Th clones shared related motifs and charged residues in their CDRs, and similar motifs were apparent even in TCR-alpha chains of human lupus Th clones. The lupus TCR-alpha chains probably contact the nucleosomal peptide complexed with MHC with relatively high affinity/avidity to sustain TCR signaling, because CD4 coreceptor was not required for promiscuous recognition. Indeed, pathogenic autoantibody-inducing, CD4-negative, TCR-alphabeta+ Th cells are expanded in systemic lupus erythematosus. These results have implications regarding thymic selection and peripheral expansion of nucleosome-specific T cells in lupus. They also suggest that universally tolerogenic epitopes could be designed for therapy of lupus patients with diverse HLA alleles. We propose to designate nucleosomes and other antigens bearing universal epitopes "Pantigens" (for promiscuous antigens). 相似文献