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101.
1 Results Recently,Ryoo‘s group reported the preparation of ordered mesoporous carbon using highly ordered mesoporous silica[1-2]. Mesoporous and nanowire SnO2 anode materials for lithium batteries were prepared using KIT-6 and SBA-15 SiO2 templates. The as-prepared SnO2 nanowires had a diameter of 6 nm and a length of ≈3 μm and Brunauer-Emmett-Teller (BET) surface area of 80 m2/g while mesoporous SnO2 showed a pore size of 3.8 nm and a BET surface area of 160 m2/g. The charge capacities of these two an... 相似文献
102.
Jae Eun Park Byoung Chul Park Hyun-A Kim Mina Song Sung Goo Park Do Hee Lee Hyeoung-Joon Kim Hyung-Kyoon Choi Jong-Tae Kim Sayeon Cho 《Cellular and molecular life sciences : CMLS》2010,67(15):2619-2629
Apoptosis signal-regulating kinase 1 (ASK1), a member of the MAP kinase kinase kinase, is activated by several death stimuli and is tightly regulated by several mechanisms such as interactions with regulatory proteins and post-translational modifications. Here, we report that dual-specificity phosphatase 13A (DUSP13A) functions as a novel regulator of ASK1. DUSP13A interacts with the N-terminal domain of ASK1 and induces ASK1-mediated apoptosis through the activation of caspase-3. DUSP13A enhances ASK1 kinase activity and thus its downstream factors. Small interfering RNA (siRNA) analyses show that knock-down of DUSP13A in human neuroblastoma SK-N-SH cells reduces ASK1 kinase activity. The phosphatase activity of DUSP13A is not required for the regulation of ASK1. This regulatory action of DSUP13 on ASK1 activity involves competition with Akt1, a negative regulator of ASK1, for binding to ASK1. Taken together, this study provides novel insights into the role of DUSP13A in the precise regulation of ASK1. 相似文献
103.
The qualitative responses that firms give to business survey questions regarding changes in their own output provide a real‐time signal of official output changes. The most commonly used method to produce an aggregate quantitative indicator from business survey responses—the net balance or diffusion index—has changed little in 40 years. This paper investigates whether an improved real‐time signal of official output data changes can be derived from a recently advanced method on the aggregation of survey data from panel responses. We find, in a New Zealand application, that exploiting the panel dimension to qualitative survey data gives a better in‐sample signal about official data than traditional methods. Out‐of‐sample, it is less clear that it matters how survey data are quantified, with simpler and more parsimonious methods hard to improve. It is clear, nevertheless, that survey data, exploited in some form, help to explain revisions to official data. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
104.
Brian Vickers 《Annals of science》2013,70(4):441-446
The characteristics of inductivist historiography of science, as practised by earlier scientist/historians, and Whig historiography, as practised by earlier political historians, are described, according to the accounts of Agassi and Butterfield. It is suggested that the writings of Geikie on the history of geology allow us to characterize him as a Whig/inductivist historian of science who formulated anachronistic judgements. It is further suggested that his writings have had a considerable long-term effect on interpretations of the history of geology. The character of Geikie's historiography is related to his social, political and religious views, his historicism, and his romantic enthusiasm for Nature. His methodological pronouncements are examined: he believed that the present is the key to the past, and also that the past is the key to the present. He was an empiricist and inductivist. These epistemological and methodological views impinged on his historiography of science. If one attempts to criticize Geikie's historiography, though one may try to judge his work according to the norms of his own day and age, historical anachronism cannot be avoided entirely and one may oneself be charged with acting ‘Whiggishly’. Historians of science, in the process of professionalization, have accepted the historiographical norms of general historians (perhaps for socio-economic reasons), but in so doing have inherited a problem that arises whenever they contemplate earlier historical writings. It is suggested that there may be more room for Whiggish historiography of science than is presently deemed acceptable. Alternatively, one may wish to draw a careful distinction between science and its meta-discipline, the historiography of science. Whig historiography conflates the two, and the work of Geikie (a scientist/historian par excellence) provides a good illustration of this. 相似文献
105.
106.
Stress produced severe mucosal ulcers, increased mucosal microcirculation and lowered mast cell counts in the glandular wall of rat stomachs. Mepyramine i.m. or metiamide i.p. effectively prevented both ulceration and microcirculatory changes but not stress-reduced mast cell counts. 相似文献
107.
Using Networked RFID equipped in warehouse or supermarket distribution, Enterprise information system (EIS) can gather and deal with cargos information. Nevertheless, when cargos are in traffic, the Networked RFID can't monitor the cargos any more as the products tagged aren't within range of a reader. This paper proposes a solution framework which combines Networked RFID and GPS tracking, and then equip with this system in container to make the cargos monitored even if the cargos are in traffic. This solution can solve the accurate consignments, position tracking and advanced theft happening through drilling holes in container. In addition, customhouse and checkpoint can get an electronic shipment manifest rapidly and safely when a vehicle gets through a checkpoint. 相似文献
108.
Brian K. Sullivan 《西北部美国博物学家》2011,46(2)
Advertisement call variation and male mating success was investigated in a population of the Arizona tree frog, Hyla wrightorum , from central Arizona. Dominant frequency of advertisement calls was significantly correlated (negatively) with male snout-vent length. Males found mating were not significantly larger than nonmating males, nor was there a significant correlation between sizes of males and females found in amplexus. These results are discussed in relation to Renaud's (1977) work with H. wrightorum and in light of recent work with anurans in general. 相似文献
109.
The Application of Critical Systems Thinking to Enhance the Effectiveness of a University Information System 总被引:1,自引:1,他引:0
Yongmei Bentley Guangming Cao Brian Lehaney 《Systemic Practice and Action Research》2013,26(5):451-465
Faced with the common problem of dissatisfaction with the outcome of investments in information systems (IS), the IS community has long sought ways to improve information systems development (ISD). This paper reports on action research (AR) that sought to improve the effectiveness a UK university’s student record system (SRS), which had exhibited persistent problems. Critical systems thinking (CST) is seen to have value for ISD and was used to guide the AR. In the first stage of this research, the issues with the initial design of the SRS were identified to have largely resulted from insufficient elicitation of the underlying assumptions about, and perspectives on, complex organisational issues. The second stage centred on examining the situation from an “ought” perspective analysing what should be done and how, in order to develop creative solutions to the problems uncovered. The third stage involved recommending solutions to address the problems identified in order to improve the effectiveness of the SRS. Overall, the AR indicates that CST enables those involved to view the design and implementation of the SRS as a holistic system, critically reflect upon broad and complex human, technological and organisational issues from different perspectives, and thereby identify creative solutions. The main contribution of this research is in generating support for an ISD intervention guided by CST. The results of, and the understanding developed from, this intervention are likely to be relevant to the problems that frequently occur in similar situations. 相似文献
110.