ALBERT

Description: Ecosystem models, specifically multispecies dynamic models, have been increasingly used to project impacts of fishing activity on the trophodynamics of ecosystems to support ecosystem-based fisheries management. Uncertainty is unavoidable in modelling processes and needs to be recognized and properly quantified before models are utilized. Uncertainty was assessed in this study for a multispecies size-spectrum model that quantifies community structure and ecological characteristics. The uncertainty was assumed to result from errors in fish life-history and metabolic scale parameters, environmental variability, fishing variability, and sampling errors. Given the same level of imprecision, metabolic scale parameters had the dominant influence on the uncertainty of the size spectrum modelling results, followed by life-history parameters. Both types of errors led to "scenario uncertainty", suggesting the possible existence of alternative states of community structure. Environmental variability, fishing variability, and observation errors resulted in "statistical uncertainty", implying that such uncertainty can be described adequately in statistical terms. The results derived from such a simulation study can provide guidance for identifying research priorities to help narrow the gap in scientific knowledge and reduce the uncertainty in fisheries management.

Description: Oxide is widely used in modifying cathode and anode materials for lithium-ion batteries. In this work, a facile method of radio magnetron sputtering is introduced to deposit a thin film on Li 4 Ti 5 O 12 composite electrodes. The pristine and modified Li 4 Ti 5 O 12 electrodes are characterized at an extended voltage range of 3–0.01 V. The reversible capacity reaches a high level of 286 mAh g –1 , which is a little less than its theoretical capacity (293 mAh g –1 ). Electrodes modified by ZnO thin films with various thickness show elevated rate capability and improved cycle performance.

Description: The extraction of Green’s functions by cross correlation of continuous seismic records at station pairs is best achieved in a diffuse wave field, where energies radiated by random sources have equal power. To partially satisfy the diffuse wave-field condition, original seismic records must be normalized as they are highly nonstationary and may have amplitude variations of orders of magnitude within the cross-correlation time window. We adapt a frequency–time normalization method to obtain seismograms with an even spectrum at all times within the data-processing unit. Compared with the commonly used one-bit normalization, the new method improves the signal-to-noise ratio of empirical Green’s functions by a factor of ~2 and increases the effective data-recording duration by a factor of 4, assuming random local and instrument noise. It yields useful Rayleigh waves at periods up to 300 s for Program for Array Seismic Studies of the Continental Lithosphere (PASSCAL)–type deployments and 600 s for permanent stations with very-broadband sensors. Thus, the new method makes it possible to extend surface-wave signals to frequencies beyond those in traditional earthquake-based surface-wave tomography at both the high- and low-frequency ends.

Description: In this work, we report a morphotropic phase boundary (MPB) involved ferromagnetic system Tb 1-x Nd x Co 2 and reveal the corresponding structural and magnetoelastic properties of this system. With high resolution synchrotron X-ray diffractometry, the crystal structure of the TbCo 2 -rich side is detected to be rhombohedral and that of NdCo 2 -rich side is tetragonal below their respective Curie temperatures T C . The MPB composition Tb 0.35 Nd 0.65 Co 2 corresponds to the coexistence of the rhombohedral phase ( R -phase) and tetragonal phase ( T -phase). Contrary to previously reported MPB involved ferromagnetic systems, the MPB composition of Tb 0.35 Nd 0.65 Co 2 shows minimum magnetization which can be understood as compensation of sublattice moments between the R -phase and the T -phase. Furthermore, magnetostriction of Tb 1-x Nd x Co 2 decreases with increasing Nd concentration until x = 0.8 and then increases in the negative direction with further increasing Nd concentration; the optimum point for magnetoelastic properties lies towards the rhombohedral phase. Our work not only shows an anomalous type of ferromagnetic MPB but also provides an effective way to design functional materials.

Description: Author(s): J.-Q. Yan, H. B. Cao, M. A. McGuire, Y. Ren, B. C. Sales, and D. G. Mandrus The spin and orbital ordering in Dy 1− x Tb x VO 3 ( x =0 and 0.2) was studied by measuring x-ray powder diffraction, magnetization, specific heat, and neutron single-crystal diffraction. The results show that G-OO/C-AF and C-OO/G-AF phases coexist in Dy 0.8 Tb 0.20 VO 3 in the temperature range 2–60 K, and the ... [Phys. Rev. B 87, 224404] Published Mon Jun 10, 2013

Description: Cenozoic rifted lacustrine basins in east China display three main basin types: (1) basins with steeply dipping boundary fault, whose hanging walls tilt along pivot points; (2) basins with listric boundary faults, whose hanging walls bend along flexural bending points; and (3) basins formed by earlier extensional rifting with later strike-slip movement superimposed. The sequence development is intimately linked to the tectonic movements in the area, where second-order sequences are regionally correlatable from basin to basin and relate to the large-scale tectonic movements in the region. Third-order sequences are related to local tectonic activity and are correlatable within basins, between subbasins, and sometimes, between neighboring basins. Detailed sequence-stratigraphic analysis and mapping of depositional systems demonstrate that sand-body distribution patterns are related to sequence-stratigraphic frameworks. For the three kinds of basins, the positions of pivot point zones, flexural bend zones, and strike-slip faults plus the syndepositional faults all control the distribution of depositional systems, systems tract, and sand bodies. These controlling factors can be attributed to different structural and stratigraphic features that change the accommodation. Structural elements include boundary faults, syndepositional faults, and abrupt changes in dip. Stratigraphic controls include preexisting surfaces with local channelization, paleobathymetric lows, and onlap onto clinoform slopes. The lowstand sand bodies deposited at the downdip end of these controlling factors constitute the current and future exploration targets for conventional reservoirs.

Description: MiR-485-3p and miR-485-5p suppress breast cancer cell metastasis by inhibiting PGC-1α expression Cell Death and Disease 7, e2159 (March 2016). doi:10.1038/cddis.2016.27 Authors: C Lou, M Xiao, S Cheng, X Lu, S Jia, Y Ren & Z Li

Description: Translational control is crucial in the regulation of gene expression and deregulation of translation is associated with a wide range of cancers and human diseases. Ribosome profiling is a technique that provides genome wide information of mRNA in translation based on deep sequencing of ribosome protected mRNA fragments (RPF). RPFdb is a comprehensive resource for hosting, analyzing and visualizing RPF data, available at www.rpfdb.org or http://sysbio.sysu.edu.cn/rpfdb/index.html . The current version of database contains 777 samples from 82 studies in 8 species, processed and reanalyzed by a unified pipeline. There are two ways to query the database: by keywords of studies or by genes. The outputs are presented in three levels. (i) Study level: including meta information of studies and reprocessed data for gene expression of translated mRNAs; (ii) Sample level: including global perspective of translated mRNA and a list of the most translated mRNA of each sample from a study; (iii) Gene level: including normalized sequence counts of translated mRNA on different genomic location of a gene from multiple samples and studies. To explore rich information provided by RPF, RPFdb also provides a genome browser to query and visualize context-specific translated mRNA. Overall our database provides a simple way to search, analyze, compare, visualize and download RPF data sets.

Description: 〈span〉〈div〉ABSTRACT〈/div〉The presently available staggered-grid finite-difference (SGFD) schemes for the 3D first-order elastic-wave equation can only achieve high-order spatial accuracy, but they exhibit second-order temporal accuracy. Therefore, the commonly used SGFD methods may suffer from visible temporal dispersion and even instability when relatively large time steps are involved. To increase the temporal accuracy and stability, we have developed a novel time-space-domain high-order SGFD stencil, characterized by (2M)th-order spatial and (2N)th-order temporal accuracies (N〈5), to numerically solve the 3D first-order elastic-wave equation. The core idea of this new stencil is to use a double-pyramid stencil with an operator length parameter N together with the conventional second-order SGFD to approximate the temporal derivatives. At the same time, the spatial derivatives are discretized by the orthogonality stencil with an operator length parameter M. We derive the time-space-domain dispersion relation of this new stencil and determine finite-difference (FD) coefficients using the Taylor-series expansion. In addition, we further optimize the spatial FD coefficients by using a least-squares (LS) algorithm to minimize the time-space-domain dispersion relation. To create accurate and reasonable P-, S-, and converted wavefields, we introduce the 3D wavefield-separation technique into our temporal high-order SGFD schemes. The decoupled P- and S-wavefields are extrapolated by using the P- and S-wave dispersion-relation-based FD coefficients, respectively. Moreover, we design an adaptive variable-length operator scheme, including operators M and N, to reduce the extra computational cost arising from adopting this new stencil. Dispersion and stability analyses indicate that our new methods have higher accuracy and better stability than the conventional ones. Using several 3D modeling examples, we demonstrate that our SGFD schemes can yield greater temporal accuracy on the premise of guaranteeing high-order spatial accuracy. Through effectively combining our new stencil, LS-based optimization, large time step, variable-length operator, and graphic processing unit, the computational efficiency can be significantly improved for the 3D case.〈/span〉