151 research outputs found
Becoming professional: Chinese accountants in early 20th century Shanghai
This paper examines the experience of Chinese accountants transforming themselves into a profession during the early 20th century. It delineates how the experience was shaped by an intersection of economic development, the political culture and the nationalist movement in semi-colonial Shanghai. Chinese accountants responded to the daily manifestations of these larger historical forces by combining their professional self-interests with a nationalist agenda and by adapting to the changing political environment. The history and legacy of this experience provides a point of reference for observing the re-emergence of the accounting profession in China since the end of the Maoist era
Both ischemic preconditioning and ghrelin administration protect hippocampus from ischemia/reperfusion and upregulate uncoupling protein-2
<p>Abstract</p> <p>Background</p> <p>A major endogenous protective mechanism in many organs against ischemia/reperfusion (I/R) injury is ischemic preconditioning (IPC). By moderately uncoupling the mitochondrial respiratory chain and decreasing production of reactive oxygen species (ROS), IPC reduces apoptosis induced by I/R by reducing cytochrome c release from the mitochondria. One element believed to contribute to reduce ROS production is the uncoupling protein UCP2 (and UCP3 in the heart). Although its implication in IPC in the brain has been shown in vitro, no in vivo study of protein has shown its upregulation. Our first goal was to determine in rat hippocampus whether UCP2 protein upregulation was associated with IPC-induced protection and increased ROS production. The second goal was to determine whether the peptide ghrelin, which possesses anti-oxidant and protective properties, alters UCP2 mRNA levels in the same way as IPC during protection.</p> <p>Results</p> <p>After global forebrain ischemia (15 min) with 72 h reperfusion (I/R group), we found important neuronal lesion in the rat hippocampal CA1 region, which was reduced by a preceding 3-min preconditioning ischemia (IPC+I/R group), whereas the preconditioning stimulus alone (IPC group) had no effect. Compared to control, UCP2 protein labelling increased moderately in the I/R (+39%, NS) and IPC+I/R (+28%, NS) groups, and substantially in the IPC group (+339%, P < 0.05). Treatment with superoxide dismutase (10000 U/kg ip) at the time of a preconditioning ischemia greatly attenuated (-73%, P < 0.001) the increase in UCP2 staining at 72 h, implying a role of oxygen radicals in UCP2 induction.</p> <p>Hippocampal UCP2 mRNA showed a moderate increase in I/R (+33%, P < 0.05) and IPC+I/R (+40%, P < 0.05) groups versus control, and a large increase in the IPC group (+333%, P < 0.001). In ghrelin experiments, the I/R+ghrelin group (3 daily administrations) showed considerable protection of CA1 neurons versus I/R animals, and increased hippocampal UCP2 mRNA (+151%, P < 0.001).</p> <p>Conclusion</p> <p>We confirm that IPC causes increased expression of UCP2 protein in vivo, at a moment appropriate for protection against I/R in the hippocampus. The two dissimilar protective strategies, IPC and ghrelin administration, were both associated with upregulated UCP2, suggesting that UCP2 may often represent a final common pathway in protection from I/R.</p
Adaptive Fuzzy Tracking Control with Global Prescribed-Time Prescribed Performance for Uncertain Strict-Feedback Nonlinear Systems
Adaptive fuzzy control strategies are established to achieve global
prescribed performance with prescribed-time convergence for strict-feedback
systems with mismatched uncertainties and unknown nonlinearities. Firstly, to
quantify the transient and steady performance constraints of the tracking
error, a class of prescribed-time prescribed performance functions are
designed, and a novel error transformation function is introduced to remove the
initial value constraints and solve the singularity problem in existing works.
Secondly, based on dynamic surface control methods, controllers with or without
approximating structures are established to guarantee that the tracking error
achieves prescribed transient performance and converges into a prescribed
bounded set within prescribed time. In particular, the settling time and
initial value of the prescribed performance function are completely independent
of initial conditions of the tracking error and system parameters, which
improves existing results. Moreover, with a novel Lyapunov-like energy
function, not only the differential explosion problem frequently occurring in
backstepping techniques is solved, but the drawback of the semi-global
boundedness of tracking error induced by dynamic surface control can be
overcome. The validity and effectiveness of the main results are verified by
numerical simulations on practical examples
Clusterization transition between cluster Mott insulators on a breathing Kagom\'{e} lattice
Motivated by recent experimental progress on various cluster Mott insulators,
we study an extended Hubbard model on a breathing Kagom\'{e} lattice with a
single electron orbital and electron filling. Two distinct types of
cluster localization are found in the cluster Mott regime due to the presence
of the electron repulsion between neighboring sites, rather than from the
on-site Hubbard interaction in the conventional Mott insulators. We introduce a
unified parton construction framework to accommodate both type of cluster Mott
insulating phase as well as a trivial Ferm liquid metal and discuss the phase
transitions in the phase diagram. It is shown that, in one of the cluster
localization phases, the strong inter-site repulsion results into locally
metallic behavior within one of two triangular clusters on the breathing
Kagom\'{e} lattice. We further comment on experimental relevance to existing
Mo-based cluster magnets.Comment: 9 pages, 3 figures. Abstracted partly from arXiv:1408.196
Attorney on trial: When lawyers met phony lawyers in republican Beijing
China underwent tremendous changes in social systems during the Republican period. Among
these changes was the government’s introduction into Chinese society of a new legal profession
based on Western ideology. Relying mainly on Shanghai archival records, previous scholarship
has suggested that, unlike the traditional litigation masters who had always been
despised by the authorities, the new Chinese lawyers quickly rose to respectable social and
economic status. However, the historical findings presented in the current article challenge
this perception by showing that in a city with a more deeply rooted indigenous legal tradition
and less influence from Western lawyers, as in Beijing, the new Chinese lawyers faced resistance
from the legacy of the old legal culture that permeated the new system. For a considerable
period of time after the establishment of the Republic, the people of Beijing still continued to hire
unqualified, “phony” lawyers in lawsuits, and some of these phony lawyers had previously
been litigation masters under the Qing dynasty. Although legal reform was instigated by
the central government as a unified policy, its implementation was bound to vary in different
regions according to the influence of the traditional legal culture. It is clear that the situation in
Shanghai and other treaty ports does not represent the situation throughout the entire country,
nor even in other coastal regions. Therefore, to make more sense of legal reform in China, one
should evaluate the development of legal reform in a particular city or region against its social
and ideological backdrop. This approach may provide insights not only into the legal reform of
the Republican period, but also into the post-Mao era when once again a modern legal system
based on the Western model has been introduced, this time within a socialist system.published_or_final_versio
Experimental study on flow-induced motion and energy conversion for two triangular prisms in tandem arrangement
Experimental tests on two tandem triangular prisms were accomplished in synergistic flow-induced motion (FIM) to collect ocean current energy (OCE) with varied spacing ratios and Reynolds number ranges. Typical FIM responses and energy conversion are discussed and presented. The effects of parameters (system stiffness, spacing ratio, and load resistance) were considered to improve the energy harvesting of the system. The main findings can be summarized as follows: 1) with varied spacing ratios between the two tandem prisms, the active power (Pharn) was up to 1.95 times that of the single triangular prism (STP); 2) In general, the harnessed OCE capacity of the upstream triangular prism (UTP) was improved, while the energy harvesting of the downstream triangular prism (DTP) was suppressed by the interaction of the two prisms, 3) In the tests, electricity was generated at U = 0.516 m/s, and the active power, which consistently increased as flow velocity increased, reached Pharn = 32.24 W, with a corresponding efficiency of ηharn = 10.31%; and 4) The best energy conservation performance for harvesting the OCE occurred at L/D = 5, and the optimal load resistance was found at RL = 11 Ω
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