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Size-dependent quantum confinement effect on electronic structure of hydrogen-terminated carbon nanodiamond (ND) cluster has been investigated at the hybrid density functional theory level. Large scale all-electron calculations have been carried out for ND clusters of 0.76 nm (29 carbons) to 7.3 nm (20 959 carbons) in diameter. It is demonstrated that the quantum confinement effect in these clusters shows strong structural dependence. An important structural factor, describing the ratio between the number of atoms within the inner core and outer shell of the cluster, is identified which dictates the size-dependent behavior of the electronic states. For ND clusters with diameter smaller than 1.5 nm, the core-shell ratio changes fast with the increase in cluster size, and the evolution of electronic properties does not follow conventional quantum confinement models. For ND clusters exceeding the threshold of 1.5 nm in diameter, the change in the core-shell ratio saturates and quantum confinement effect becomes visible. Electronic states within the inner core and surface show different size dependence, but a general formula is proposed and describes their structure dependent quantum confinement effects. This formula provides useful insights into quantum confinement behavior in ND clusters, and thereby leads to important physical property information. The calculated electron effective masses for core and surface states of ND clusters are in very good agreement with the experiments. [ABSTRACT FROM AUTHOR]

* Premise of the study: Expressed sequence tag (ESTs)--derived microsatellite markers were developed in Lathyrus sativus by screening the National Center for Biotechnology Information (NCBI) database. The usefulness of these novel markers was validated for size polymorphism among grasspea accessions. * Methods and Results: Three hundred EST--simple sequence repeat (SSR) primer pairs were identified and loci characterized for size polymorphism among 24 grasspea accessions from worldwide sources. Among them 139 SSR loci produced no PCR product, 117 SSR loci were monomorphic, and 44 SSR loci were polymorphic. The mean number of alleles per locus ranged from two to 11. The observed heterozygosity and expected heterozygosity ranged from 0.000 to 1.000 and 0.042 to 0.836, respectively. * Conclusions: These novel markers will be useful and convenient to study genetic mapping and molecular breeding in grasspea. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the slag powder''s fineness, the amounts of activator, type and contents of modification addition on the dry–shrinkage and strength of the high-strength slag cement material was investigated. The experimental data showed that adding 9% Na2SiO3 activator and 10% Portland cement (PC) made the ratios of drying–shrinkage of high-strength slag cement material similar to the ratios of Portland cement and the compressive strengths as higher. The main hydration products are calcium alumina–silicate gels and a little CH; the gel ratio of CaO/SiO2 is close to 1 and includes a little Na2O and MgO for high-strength slag cement material, as shown by means of scanning electron microscope (SEM) and energy-dispersive X-ray analyzer (EDXA). [Copyright &y& Elsevier]

This article aims to provide evidence on the potential sources of gains associated with railroad mergers. The U.S. railroad industry has experienced unprecedented reorganization and consolidation, resulting in fewer but larger firms in the industry. This article examines stock market reactions to railroad mergers to determine the factors which motivate the mergers. One of the reasons for railroad mergers is to achieve operation synergy or economies of scale. Two railroads may also merge for potential gains through the exercise of market power.

We study the spin-dependent transport through a one-dimensional quantum ring with taking both the Rashba spin--orbit coupling (RSOC) and ferromagnetic leads into consideration. The linear conductance is obtained by the Green's function method. We find that due to the quantum interference effect arising from the RSOC-induced spin precession phase and the difference in travelling phase between the two arms of the ring, the conductance becomes spin-polarized even in the antiparallel magnetic configuration of the two leads, which is different from the case in single conduction channel system. The linear conductance, the spin polarization and the tunnel magnetoresistance are periodic functions of the two phases, and can be efficiently tuned by the structure parameters. [ABSTRACT FROM AUTHOR]

The article presents a study on T-box transcription factor 3 (Tbx3)-derived neuronal lineage and Tbx3-dependent neuronal specification which found that Tbx3 hierarchically established and maintained the identity of KNDy neurons for triggering puberty. Topics include effect of Tbx3 deficiency on the identity establishment of KNDy, specific deletion of Tbx3 in KNDy neurons which undermines their identity maintenance, and significance of identity maintenance of KNDy neurons for puberty onset.

The existence of the channel state information (CSI) gave the communication system self-adaptation to the channel, and guaranteed the high-speed and high reliable communication for multiple-input multiple-output (MIMO) systems. It was often practical for the receivers to get the CSI, while it needed some condition for the CSI at transmitters (CSIT). Capacity was the most important measurement for the transmission capability of channel, and degree of freedom (DoF) was the main factor to represent the linear scalability of the capacity. As a result, the existence of CSIT would affect to the capacity and DoF of MIMO networks. This paper studied and compared the impact to the DoF and region of DoF of the MIMO networks by the CSIT in different constraints, including the broadcasting channel (BC), interference channel (IC), X channel (XC). Finally it concluded that CSIT could increase the DoF in the most scenarios for these networks. The region of DoF of MIMO XC with CSIT, the DoF and region of DoF of multi networks coexistence need further research. [ABSTRACT FROM AUTHOR]

Lithospheric thickness is closely associated with lithospheric response to tectonic forces or thermal processes. Analysis of S-wave receiver functions (SRFs) from a dense seismic array has revealed lithospheric thickness variations along a 1200 km long profile that spans all major geological terranes of Northeast China. The SRF images identify the shallowest Moho and lithosphere-asthenosphere boundary (LAB) depths beneath the rifted Songliao Basin, thus spatially correlating well with the thick sediment accumulation. These features can be explained by a pure shear regime operating in the lower crust and upper mantle, suggesting the predominance of roughly symmetric lithosphere stretching from continental rifting. In contrast, thicker lithosphere in western and eastern terranes of NE China indicates the lithosphere in these regions was not strongly affected by the extensional processes during the Late Mesozoic. Flat LAB structure beneath the Erguna and Xing'an terranes along with the overlying relatively deeper Moho beneath the Great Xing'an Range, suggests the North-South Gravity Lineament may not be a trans-lithospheric structure. [ABSTRACT FROM AUTHOR]

Background: Faba bean (Vicia faba L.) is an important food legume crop, grown for human consumption globally including in China, Turkey, Egypt and Ethiopia. Although genetic gain has been made through conventional selection and breeding efforts, this could be substantially improved through the application of molecular methods. For this, a set of reliable molecular markers representative of the entire genome is required. Results: A library with 125,559 putative SSR sequences was constructed and characterized for repeat type and length from a mixed genome of 247 spring and winter sown faba bean genotypes using 454 sequencing. A suit of 28,503 primer pair sequences were designed and 150 were randomly selected for validation. Of these, 94 produced reproducible amplicons that were polymorphic among 32 faba bean genotypes selected from diverse geographical locations. The number of alleles per locus ranged from 2 to 8, the expected heterozygocities ranged from 0.0000 to 1.0000, and the observed heterozygosities ranged from 0.0908 to 0.8410. The validation by UPGMA cluster analysis of 32 genotypes based on Nei's genetic distance, showed high quality and effectiveness of those novel SSR markers developed via next generation sequencing technology. Conclusions: Large scale SSR marker development was successfully achieved using next generation sequencing of the V. faba genome. These novel markers are valuable for constructing genetic linkage maps, future QTL mapping, and marker-assisted trait selection in faba bean breeding efforts. [ABSTRACT FROM AUTHOR]

In this work, the thermal properties of a single-walled carbon nanotube (SWCNT) crystal are studied. The thermal conductivity of the SWCNT crystal is found to have a linear dependence on temperature in the temperature range from 1.9 K to 100.0 K. In addition, a peak (658 W/mK) is found at a temperature of about 100.0 K. The thermal conductivity decreases gradually to a value of 480 W/mK and keeps almost a constant in the temperature range from 100.0 K to 300.0 K. Meanwhile, the specific heat shows an obvious linear relationship with temperature in the temperature range from 1.9 K to 300.0 K. We discuss the possible mechanisms for these unique thermal properties of the single-walled carbon nanotube crystal. [ABSTRACT FROM AUTHOR]