2,335 research outputs found

    金剛ēŸ³é‰†é€²čƒ½é‡čˆ‡čŠ±å“—巖地層é¢Ø化ē؋åŗ¦ēš„é—œē³»

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    Based on experimental data from a drilling process monitoring system instrumented with a hydraulic rotary drill rig in fill-weathered granite formation, the diamond penetrating energy was analyzed. The result shows that the distribution of the penetrating energy in fill-weathered granite formation agrees with that in common weathered granite formation. A negative correlation between the viscous energy, kinetic energy, total penetrating energy and the weathered degree of granite existed, and a positive correlation between the thrust force energy and the weathered degree was presented, which indicates that there is a well response between the penetrating energy and the weathered degree of rock. However, the kinetic energy, thrust force energy and viscous energy are limited in identification of formation because of different effects in various drilling modes. The specific energy of diamond drilling (SEDD) increased with the weathered degree of rock and the values of SEDD can be classified into corresponding range according to the weathered degree of rock. It is shown that the SEDD in rotary drilling is apparently less than the specific energy of percussive drilling (SEPD) in both fill soil and very strongly weathered granite formation. Reversely, the SEDD is much more than the SEPD in lightly weathered hard rock.link_to_subscribed_fulltex

    Spin texture and magnetoroton excitations at nu=1/3

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    Neutral spin texture (ST) excitations at nu=1/3 are directly observed for the first time by resonant inelastic light scattering. They are determined to involve two simultaneous spin flips. At low magnetic fields, the ST energy is below that of the magnetoroton minimum. With increasing in-plane magnetic field these mode energies cross at a critical ratio of the Zeeman and Coulomb energies of eta(c)=0.020 +/- 0.001. Surprisingly, the intensity of the ST mode grows with temperature in the range in which the magnetoroton modes collapse. The temperature dependence is interpreted in terms of a competition between coexisting phases supporting different excitations. We consider the role of the ST excitations in activated transport at nu=1/3

    Interface identification in weathered granite strata based on a instrumented drilling system

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    A hydraulic rotary drill instrumented with a drilling process monitoring system (DPM) was used for site investigation in Hong Kong weathered granite foundation engineering. The penetrating parameters such as effective thrust force, rotational speed, flushing pressure, penetrating rate and displacement of the bit were monitored in real time. A varied slope was defined as a significant index for identification of dominative and subsidiary interfaces in the granite site. The result from t-test shows that the confidence of the DPM in identification of the geotechnical interfaces is 99%. Besides, the analysis of variation of the penetrating parameters at the interfaces indicates that there are different fluctuations at the interfaces in the curves of the parameters with borehole depth. The response degree of effective thrust force and penetrating rate to the variation of rock strength at the interfaces is 81.82% alone.link_to_subscribed_fulltex

    Theory and approach of identification of ground interfaces based on rock drillability index

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    Rock drillability index is a very key parameter in selection of drill bit type and determination of productivity in petroleum, mining and geology. Unfortunately, there are many limits in the current definition as well as experimental methods. Drillability is redefined and a new concept of drillability index is brought out from analysis. Under the new concept, the drillability index is defined as penetration rate under specific energy. Based on the coupling relationship among effective thrust, rotation speed, penetration rate and drillability index, a calculation formula is established. Besides, the sensitivity of the drillability index in identification of ground layer is analyzed and its physical signification is expatiated also. The result shows that the new index overcomes the blind area in the traditional concept and can be used in continuous identification of ground layer along borehole profile.link_to_subscribed_fulltex

    Collaborative Consumption On Mobile Applications: A Study Of Multi-sided Digital Platform GoCatch

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    This paper examines the role of IT in developing collaborative consumption. We present a study of the multi-sided platform goCatch, which is widely recognized as a mobile application and digital disruptor in the Australian transport industry. From our investigation, we find that goCatch uses IT to create situational-based and object-based opportunities to enable collaborative consumption and in turn digital disruption to the incumbent industry. We also highlight the factors to consider in developing a mobile application to connect with customers, and serve as a viable competitive option for responding to competition. Such research is necessary in order to better understand how service providers extract business value from digital technologies to formulate new breakthrough strategies, design compelling new products and services, and transform management processes. Ongoing work will reveal how m-commerce service providers can extract business value from a collaborative consumption model

    Cultural Adaptation and Linguistic Validation of the Beliefs about Medicines Questionnaire in Malaysia

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    BACKGROUND: Low rate of adherence was found strongly associated with patients' beliefs across the studies about chronic diseases with hypertension. A crucial move is needed to bridge the gap between appropriate assessment tools and local hypertensive patients' medication adherence. OBJECTIVE: To produce a translated version in Malay language of Beliefs about Medicines Questionnaire (BMQ) that was "conceptually equivalent" to the original English version for use in local clinical practice and research. METHODS: The forward translation process was conducted by two independent professional translators and back translation was done by two other independent translators. A reliability analysis was conducted on 238 conveniently selected hypertensive patients. Intraclass correlation coefficient (ICC) was used to assess test-retest reliability for the randomly selected 40 patients in a period of 2 weeks. Discriminant validity was tested through Necessity-Concerns differential, BMQ subscales, and other parameters. RESULTS: The overall Cronbach alpha for the internal consistency was good (0.860). The subscales of the BMQ demonstrated adequate internal consistency, with Cronbach alpha value of 0.759 for Specific-Necessity, 0.762 for Specific Concern, 0.624 for General-Overuse, and 0.756 for General-Harm. The ICC was excellent (0.922). Discriminant validity revealed that BMQ Specific-Necessity score was significantly inversely correlated with the systolic blood pressure level. Systolic and diastolic blood pressure levels (P = 0.038; P = 0.05) were reported to be significantly correlated with the Necessity-Concerns differential, with Necessity score equal or exceeding Concerns score. CONCLUSIONS: The Malay-translated version of BMQ is a reliable and valid tool to assess patient belief about medication, especially medication adherence among the hypertensive patients in Malaysia

    Full length talin stimulates integrin activation and axon regeneration.

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    Integrin function is regulated by activation involving conformational changes that modulate ligand-binding affinity and downstream signaling. Activation is regulated through inside-out signaling which is controlled by many signaling pathways via a final common pathway through kindlin and talin, which bind to the intracellular tail of beta integrins. Previous studies have shown that the axon growth inhibitory molecules NogoA and chondroitin sulfate proteoglycans (CSPGs) inactivate integrins. Overexpressing kindlin-1 in dorsal root ganglion (DRG) neurons activates integrins, enabling their axons to overcome inhibitory molecules in the environment, and promoting regeneration in vivo following dorsal root crush. Other studies have indicated that expression of the talin head alone or with kindlin can enhance integrin activation. Here, using adult rat DRG neurons, we investigate the effects of overexpressing various forms of talin on axon growth and integrin signaling. We found that overexpression of the talin head activated axonal integrins but inhibited downstream signaling via FAK, and did not promote axon growth. Similarly, co-expression of the talin head and kindlin-1 prevented the growth-promoting effect of kindlin-1, suggesting that the talin head acts as a form of dominant negative for integrin function. Using full-length talin constructs in PC12 cells we observed that neurite growth was enhanced by the expression of wild-type talin and more so by two 'activated' forms of talin produced by point mutation (on laminin and aggrecan-laminin substrates). Nevertheless, co-expression of full-length talin with kindlin did not promote neurite growth more than either molecule alone. In vivo, we find that talin is present in PNS axons (sciatic nerve), and also in CNS axons of the corticospinal tract.This work was funded by grants from the Medical Research Council (G1000864), the Henry Smith Charity, the Christopher and Dana Reeve Foundation, the John and Lucille van Geest Foundation, the European Union Framework 7 Programmes Spinal Cord Repair (201144) and Plasticise (223524), and the NIHR Cambridge Biomedical Research Centre. CLT was supported by the Merck, Sharpe and Dohme Fund. We thank Rienhardt Fassler for kindlin constructs and advice, David Critchley for talin antibodies and constructs and Mark Ginsberg for talin constructs.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.mcn.2015.03.01
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