APC Communiqué

This is the archive of the fall 2012 APC communiqué, a bi-annual newsletter, which has a special report on Ambassador Zhong Jianhua's visit entitled "China’s Africa Envoy discusses China-Africa relations

Fog-enabled Edge Learning for Cognitive Content-Centric Networking in 5G

By caching content at network edges close to the users, the content-centric networking (CCN) has been considered to enforce efficient content retrieval and distribution in the fifth generation (5G) networks. Due to the volume, velocity, and variety of data generated by various 5G users, an urgent and strategic issue is how to elevate the cognitive ability of the CCN to realize context-awareness, timely response, and traffic offloading for 5G applications. In this article, we envision that the fundamental work of designing a cognitive CCN (C-CCN) for the upcoming 5G is exploiting the fog computing to associatively learn and control the states of edge devices (such as phones, vehicles, and base stations) and in-network resources (computing, networking, and caching). Moreover, we propose a fog-enabled edge learning (FEL) framework for C-CCN in 5G, which can aggregate the idle computing resources of the neighbouring edge devices into virtual fogs to afford the heavy delay-sensitive learning tasks. By leveraging artificial intelligence (AI) to jointly processing sensed environmental data, dealing with the massive content statistics, and enforcing the mobility control at network edges, the FEL makes it possible for mobile users to cognitively share their data over the C-CCN in 5G. To validate the feasibility of proposed framework, we design two FEL-advanced cognitive services for C-CCN in 5G: 1) personalized network acceleration, 2) enhanced mobility management. Simultaneously, we present the simulations to show the FEL's efficiency on serving for the mobile users' delay-sensitive content retrieval and distribution in 5G.Comment: Submitted to IEEE Communications Magzine, under review, Feb. 09, 201

Chern numbers and chiral anomalies in Weyl butterflies

The Hofstadter butterfly of lattice electrons in a strong magnetic field is a cornerstone of condensed matter physics, exploring the competition between periodicities imposed by the lattice and the field. In this work we introduce and characterize the Weyl butterfly, which emerges when a large magnetic field is applied to a three-dimensional Weyl semimetal. Using an experimentally motivated lattice model for cold atomic systems, we solve this problem numerically. We find that Weyl nodes reemerge at commensurate fluxes and propose using wavepackets dynamics to reveal their chirality and location. Moreover, we show that the chiral anomaly -- a hallmark of the topological Weyl semimetal -- does not remain proportional to magnetic field at large fields, but rather inherits a fractal structure of linear regimes as a function of external field. The slope of each linear regime is determined by the difference of two Chern numbers in gaps of the Weyl butterfly and can be measured experimentally in time of flight.Comment: 4 pages, 4 figures + supplementary material, version accepted in Phys. Rev. B as a Rapid Communicatio

Sparse whole-genome sequencing identifies two loci for major depressive disorder.

Major depressive disorder (MDD), one of the most frequently encountered forms of mental illness and a leading cause of disability worldwide, poses a major challenge to genetic analysis. To date, no robustly replicated genetic loci have been identified, despite analysis of more than 9,000 cases. Here, using low-coverage whole-genome sequencing of 5,303 Chinese women with recurrent MDD selected to reduce phenotypic heterogeneity, and 5,337 controls screened to exclude MDD, we identified, and subsequently replicated in an independent sample, two loci contributing to risk of MDD on chromosome 10: one near the SIRT1 gene (P = 2.53 × 10(-10)), the other in an intron of the LHPP gene (P = 6.45 × 10(-12)). Analysis of 4,509 cases with a severe subtype of MDD, melancholia, yielded an increased genetic signal at the SIRT1 locus. We attribute our success to the recruitment of relatively homogeneous cases with severe illness

Eocene–early Oligocene climate and vegetation change in southern China: Evidence from the Maoming Basin

Although the Eocene-Oligocene climate transition marks a critical point in the development of the ‘icehouse’ global climate of the present little is known about this important change in the terrestrial realm at low latitudes. Our palynological study of the Shangcun Formation shows it to be early Oligocene in age: palyno-assemblages in the lower part of the formation indicate a cool interval dominated by conifer pollen in the earliest Oligocene followed by a warmer regime in the second half of the early Oligocene. To quantify middle Eocene to late early Oligocene climate conditions at low (~ 20°N) palaeolatitudes in southern Asia several thousand leaf fossil specimens from the Maoming Basin, southern China, were subjected to a multivariate (CLAMP) analysis of leaf form. For terrestrial palaeoclimate comparisons to be valid the palaeoaltitude at which the proxy data are obtained must be known. We find that leaves preserved in the Youganwo (middle Eocene), Huangniuling (late Eocene) and Shangcun (early Oligocene) formations were likely to have been deposited well above sea level at different palaeoelevations. In the Youganwo Formation fine-grained sediments were deposited at an altitude of ~ 1.5 km, after which the basin dropped to ~ 0.5 km by the time the upper Huangniuling sediments were deposited. The basin floor then rose again by 0.5 km reaching an altitude of approximately 1 km in which the Shangcun Formation fine-grained sediments were accumulated. Within the context of these elevation changes the prevailing climates experienced by the Youganwo, Lower Huangniuling, Upper Huangniuling and Shangcun fossil floras were humid subtropical with hot summers and warm winters, but witnessed a progressive increase in rainfall seasonality. By the early Oligocene rainfall seasonality was similar to that of the modern monsoonal climate of Guangdong Province, southern China. All floras show leaf physiognomic spectra most similar to those growing under the influence of the modern Indonesia-Australia Monsoon, but with no evidence of any adaptation to today's South or East Asia Monsoon regimes. The Upper Huangniuling Flora, rich in dipterocarp plant megafossils, grew in the warmest conditions with the highest cold month mean temperature and at the lowest altitude

Effect of Chinese massage (Tui Na) on isokinetic muscle strength in patients with knee osteoarthritis

AbstractObjectiveChinese massage (Tui Na) is one of the most popular Traditional Chinese Medicine remedies for knee osteoarthritis (OA). Several studies have subjectively evaluated the effect of Chinese massage on knee OA through self-assessment questionnaires; however, very few studies have objectively assessed the effect by measuring knee muscle strength. The purpose of this study was to assess the efficacy of Chinese massage in improving knee extensor and flexor muscle strength in patients with knee OA.MethodsThirty patients with knee OA received Chinese massage therapy three times per week for 2 weeks. Patients completed pre- and post-treatment Visual Analogue Scale (VAS) pain questionnaires, and pre- and post-treatment knee muscle strength was evaluated using the Biodex Multi-Joint System 3. Isokinetic muscle strength measurements were performed at 60 degrees/s and 180 degrees/s. The peak torque (PT), peak torque/body weight (PT/BW), total work (TW), average power (AP), hamstring/quadriceps (H/Q), and range of motion (ROM) values were recorded separately for flexors and extensors.ResultsChinese massage therapy significantly improved knee pain as assessed by the VAS in patients with knee OA (P < 0.05). Post-treatment values were significantly greater than pre-treatment values in the extensor muscles for PT (right P = 0.013, left P = 0.001), PT/BW (right P = 0.008, left P = 0.001) and TW (right P = 0.036, left P = 0.004) at 60 degrees/s. The AP increased significantly after treatment in the flexor muscles in the right knee (P = 0.009) and the extensor muscles in the left knee (P = 0.001). There were no significant differences in pre- and post-treatment ROM and H/Q at 60 degrees/s and 180 degrees/s.ConclusionChinese massage therapy decreased pain and may improve extensor muscle strength in patients with knee OA, but does not appear to improve ROM