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101.
Natasha L. Mikles 《Material Religion》2020,16(2):187-212
AbstractBased on interviews performed in Qinghai, this article examines the ritual for creating the “mountain hat” used by bards of Tibet’s Gesar epic in the Yushu and Golok provinces to argue for its importance in constructing local ideas of identity and authority. After introducing a typology of bardic hats, this paper relates the two-week ritual to make a “mountain hat” and analyses how it unites epic narrative, local ideas of place, and the authority of Buddhist institutions into a single, distinctive object used in the performance arena. Utilizing David Morgan’s work on embodiment and identity through the act of seeing, this article argues for the “mountain hat” as a microcosm of a religious imaginary that influences and shapes the viewer’s and the bard’s self-understanding. Additionally, this article considers the interpretation of the “mountain hat” and the religious imaginary it represents in the larger context of contemporary Tibet, where competing forms of economic and cultural authority challenge Tibetans’ experience. Ultimately, this article draws attention to the central role of ritual in constructing the “mountain hat” and imbuing it with the necessary symbolic complexes to become a potent visual object of identity. 相似文献
102.
Dave DeSimone Natasha Ghezawi Thomas Gaetjens Robert Counce Jack Watson 《溶剂提取与离子交换》2013,31(6):422-434
ABSTRACTExtraction of yttrium (Y) from sulfuric acid was studied using di(2-ethylhexyl) phosphate (DEHPA). A portion of the organic phase was recycled back into the mixer after extraction for the mixer to operate at a moderate organic-to-aqueous volumetric phase ratio while processing at a low organic-to-aqueous flow rate ratio. The effective performance of the mixer was evaluated when operating at different organic-phase flow fractions. To model the extraction rate coefficient, a 2-factor designed experiment was performed by conducting both equilibrium and mixer-settler tests. The organic-phase flow fraction was varied over four discrete levels while the extractant concentration was varied over three discrete levels. Increasing the organic-phase flow fraction yielded a continual increase in the extraction rate coefficient. In contrast, increasing the extractant concentration yielded an initial increase followed by a subsequent decrease in the extraction rate coefficient. The decline in the extraction rate coefficient was attributed to a decrease in the yttrium-extractant complex’s diffusion coefficient. High metal loading caused an elevated organic-phase viscosity and thus the low diffusion coefficient. An extraction rate coefficient model is proposed to describe the effects of extractant concentration, viscosity and organic-phase flow fraction. Mass transfer resistance was largely in the organic phase. 相似文献
103.
Gregg J. Lumetta Amanda J. Casella Brian M. Rapko Tatiana G. Levitskaia Natasha K. Pence Jennifer C. Carter 《溶剂提取与离子交换》2013,31(3):211-223
A method for separating the trivalent actinides and lanthanides is being developed using 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) as the extractant. The method is based on the preferential binding of the actinides in the aqueous phase by N-(2-hydroxyethyl)ethylenediamine-N,N’,N’-triacetic acid (HEDTA), which serves to keep the actinides in the aqueous phase while the lanthanides are extracted into an organic phase containing HEH[EHP]. The process is very robust, showing little dependence upon the pH or the HEH[EHP], HEDTA, and citrate concentrations over the ranges that might be expected in a nuclear fuel recycling plant. Single-stage runs with a 2-cm centrifugal contactor indicate that modifications to the process chemistry may be needed to increase the extraction rate for Sm, Eu, and Gd. The hydraulic properties of the system are favorable to application in centrifugal contactors. 相似文献
104.
105.
Diamond Adele; Churchland Anne; Cruess Loren; Kirkham Natasha Z. 《Canadian Metallurgical Quarterly》1999,35(6):1507
Delayed nonmatching to sample (DNMS) is used to test the recognition memory function dependent on the medial temporal lobe. Children cannot succeed on this task until about 21 months. Because robust recognition is present well before then, the late emergence of another ability must account for the late success on DNMS. Evidence is presented here that the critical late-maturing confidence is the ability to grasp the relation between stimulus and reward—that is, to understand that the stimulus is a symbol or marker for the reward. Infants of 9 and 12 months were tested on 3 conditions of DNMS. A sample object was presented. After a delay, the sample and a novel object appeared; choice of the novel object was rewarded. In the standard task, the reward was in a well beneath the stimulus. In the verbal-reward condition the reward was not a separate object but was praise and applause. In the Velcro condition, the reward, although a separate and separable object, was attached to the base of the stimulus. Most infants at both ages succeeded in the verbal-reward and Velcro conditions but not in the standard condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Natasha de Alwis Natalie K. Binder Yeukai T. M. Mangwiro Sally Beard Natasha Pritchard Elif Kadife Bianca R. Fato Emerson Keenan Fiona C. Brownfoot Tuuhevaha J. Kaituu-Lino Natalie J. Hannan 《International journal of molecular sciences》2022,23(15)
Preeclampsia is a devastating, multisystem disorder of pregnancy. It has no cure except delivery, which if premature can impart significant neonatal morbidity. Efforts to repurpose pregnancy-safe therapeutics for the treatment of preeclampsia have led to the assessment of the proton pump inhibitor, esomeprazole. Preclinically, esomeprazole reduced placental secretion of anti-angiogenic sFlt-1, improved endothelial dysfunction, promoted vasorelaxation, and reduced maternal hypertension in a mouse model. Our understanding of the precise mechanisms through which esomeprazole works to reduce endothelial dysfunction and enhance vasoreactivity is limited. Evidence from earlier studies suggested esomeprazole might work via the nitric oxide pathway, upregulating endothelial nitric oxide synthase (eNOS). Here, we investigated the effect of esomeprazole in a mouse model of L-NAME-induced hypertension (decreased eNOS activity). We further antagonised the model by addition of diet-induced obesity, which is relevant to both preeclampsia and the nitric oxide pathway. Esomeprazole did not decrease blood pressure in this model, nor were there any alterations in vasoreactivity or changes in foetal outcomes in lean mice. We observed similar findings in the obese mouse cohort, except esomeprazole treatment enhanced ex vivo acetylcholine-induced vasorelaxation. As acetylcholine induces nitric oxide production, these findings hint at a function for esomeprazole in the nitric oxide pathway. 相似文献
107.
Predicate Abstraction of ANSI-C Programs Using SAT 总被引:1,自引:0,他引:1
Edmund Clarke Daniel Kroening Natasha Sharygina Karen Yorav 《Formal Methods in System Design》2004,25(2-3):105-127
Predicate abstraction is a major method for verification of software. However, the generation of the abstract Boolean program from the set of predicates and the original program suffers from an exponential number of theorem prover calls as well as from soundness issues. This paper presents a novel technique that uses an efficient SAT solver for generating the abstract transition relations of ANSI-C programs. The SAT-based approach computes a more precise and safe abstraction compared to existing predicate abstraction techniques. 相似文献
108.
109.
Robert Malkin Thomas R. McDonagh Natasha Mhatre Thomas S. Scott Daniel Robert 《Journal of the Royal Society Interface》2014,11(90)
Animal ears are exquisitely adapted to capture sound energy and perform signal analysis. Studying the ear of the locust, we show how frequency signal analysis can be performed solely by using the structural features of the tympanum. Incident sound waves generate mechanical vibrational waves that travel across the tympanum. These waves shoal in a tsunami-like fashion, resulting in energy localization that focuses vibrations onto the mechanosensory neurons in a frequency-dependent manner. Using finite element analysis, we demonstrate that two mechanical properties of the locust tympanum, distributed thickness and tension, are necessary and sufficient to generate frequency-dependent energy localization. 相似文献
110.
Jonathan Tzadikov Natasha Ronith Levy Liel Abisdris Reut Cohen Michal Weitman Ilia Kaminker Amir Goldbourt Yair Ein‐Eli Menny Shalom 《Advanced functional materials》2020,30(19)
The fabrication of sulfur‐containing carbonaceous anode materials (CS) that show exceptional activity as anode material in Na‐ions batteries is reported. To do so, a general and straightforward bottom‐up synthesis of CS materials with precise control over the sulfur content and functionality is introduced. The new synthetic path combined with a detailed structural analysis and electrochemical studies provide correlations between i) the sulfur content and chemical species and ii) the structural, electronic, and electrochemical performance of the associated materials. As a result, the new CS substances demonstrate excellent activity as Na‐ion battery anode materials, reaching capacity values above 500 mAh g?1 at a current density of 0.1 A g?1, as well as high reversible sodium storage capabilities and excellent cycling durability. The results reveal the underlying working principles of carbonaceous materials, alongside the storage mechanism of the Na+ ions in these advanced sodium‐ion battery anode materials and provide a new avenue for their practical realization. 相似文献