A Comparison between the Zero Forcing Number and the Strong Metric Dimension of Graphs

The \emph{zero forcing number}, $Z(G)$, of a graph $G$ is the minimum cardinality of a set $S$ of black vertices (whereas vertices in $V(G)-S$ are colored white) such that $V(G)$ is turned black after finitely many applications of "the color-change rule": a white vertex is converted black if it is the only white neighbor of a black vertex. The \emph{strong metric dimension}, $sdim(G)$, of a graph $G$ is the minimum among cardinalities of all strong resolving sets: $W \subseteq V(G)$ is a \emph{strong resolving set} of $G$ if for any $u, v \in V(G)$, there exists an $x \in W$ such that either $u$ lies on an $x-v$ geodesic or $v$ lies on an $x-u$ geodesic. In this paper, we prove that $Z(G) \le sdim(G)+3r(G)$ for a connected graph $G$, where $r(G)$ is the cycle rank of $G$. Further, we prove the sharp bound $Z(G) \leq sdim(G)$ when $G$ is a tree or a unicyclic graph, and we characterize trees $T$ attaining $Z(T)=sdim(T)$. It is easy to see that $sdim(T+e)-sdim(T)$ can be arbitrarily large for a tree $T$; we prove that $sdim(T+e) \ge sdim(T)-2$ and show that the bound is sharp.Comment: 8 pages, 5 figure

Impacts of Ti content and annealing temperature on electrical properties of Si MOS capacitors with HfTiON gate dielectric

Proceedings of the IEEE International Conference of Electron Devices and Solid-State Circuits, 2009, p. 221-224HfTiON gate dielectric is fabricated by reactive co-sputtering method followed by annealing in N 2 ambient. The effects of Ti content and annealing temperature on the performances of HfTiON gate-dielectric Si MOS devices are investigated. Experimental results indicate that gate capacitance is increased with increasing Ti content. However, when the Ti/Hf ratio exceeds -1.75, increase of the gate capacitance becomes small. Surface roughness of the samples annealed at different temperatures is analyzed by AFM, and results show that high annealing temperature (e.g. 700 °C for 30 s) can produce smooth surface, thus resulting in low gate leakage current. ©2009 IEEE.published_or_final_versio

Electrical properties of HfTiON gate-dielectric metal-oxide-semiconductor capacitors with different Si-surface nitridations

Electrical properties of HfTiON gate-dielectric metal-oxide-semiconductor (MOS) capacitors with different Si-surface nitridations in N2 O, NO, and N H3 prior to high- k film deposition are investigated and compared. It is found that the NO-nitrided sample exhibits low interface-state density and gate leakage current, and high reliability. This is attributed to formation of a SiON interlayer with suitable proportions of N and O. The MOS capacitor with Hf0.4 Ti0.6 Ox Ny SiON gate dielectric stack (capacitance equivalent thickness of 1.52 nm and k value of 18.9) prepared by NO surface nitridation has an interface-state density of 1.22× 1011 cm-2 eV-1 and gate leakage current density of 6× 10-4 A cm-2 (Vg =1 V). Moreover, only a small degradation of electrical properties after a stressing at 10 MVcm for 3000 s is observed for the NO-nitrided sample. © 2007 American Institute of Physics.published_or_final_versio

Arthroscopic Removal of Suprapatellar Fibroma of Tendon Sheath

Fibroma of tendon sheath (FTS) is a rare dense fibrous benign tumor that majorities are found over the tendons or tendon sheaths of limbs, with predilection in order starting with fingers, hands, wrists, and other parts.1 Almost 80% of tendon sheath fibromas are found over hands and wrists.2 The typical morphological feature is a solid nodule that is painless and slow growing in nature. Fibromas of tendon sheath rarely arise from knee joints. To our best knowledge, less than 20 such cases have been reported, and none of them was a Chinese patient. We present a case of intra-articular fibroma of tendon sheath of the knee that was excised arthroscopically.published_or_final_versio

Improved electrical properties of metal-oxide-semiconductor capacitor with HfTiON gate dielectric by using HfSiON interlayer

Metal-oxide-semiconductor (MOS) capacitor with HfTiONHfSiON stack structure as high- k gate dielectric is fabricated, and its electrical properties are compared with those of a similar device with HfTiON only as gate dielectric. Experimental results show that the device with HfTiONHfSiON gate dielectric exhibits better interface properties, lower gate leakage current, and enhanced high-field reliability. All these improvements should be attributed to the fact that the HfSiON buffer layer effectively blocks the diffusion of Ti atoms to the Si substrate, thus resulting in a Si O2 Si -like HfSiONSi interface. © 2007 American Institute of Physics.published_or_final_versio

A compact threshold-voltage model of MOSFETs with stack high-k gate dielectric

In this paper, a compact threshold-voltage model is developed for stack high-k gate-dielectric MOSFET with a thin interiayer. The simulated results are in good agreement with 2-D simulations. The influences of k value of the interlayer on threshold behaviors are investigated in detail. A low-k interlayer can effectively improve the threshold-voltage behaviors. Furthermore, the ratio of low-k interiayer EOT (equivalent oxide thickness) to high-k layer EOT is optimized by considering both threshold-voltage roll-off and gate leakage current. ©2009 IEEE.published_or_final_versionThe IEEE International Conference of Electron Devices and Solid-State Circuits (EDSSC 2009), Xian, China, 25-27 December 2009. In Proceedings of EDSSC, 2009, p. 236-23

Effectiveness of varenicline and counseling for smoking cessation in an observational cohort study in China

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Demagnetization of Quantum Dot Nuclear Spins: Breakdown of the Nuclear Spin Temperature Approach

The physics of interacting nuclear spins arranged in a crystalline lattice is typically described using a thermodynamic framework: a variety of experimental studies in bulk solid-state systems have proven the concept of a spin temperature to be not only correct but also vital for the understanding of experimental observations. Using demagnetization experiments we demonstrate that the mesoscopic nuclear spin ensemble of a quantum dot (QD) can in general not be described by a spin temperature. We associate the observed deviations from a thermal spin state with the presence of strong quadrupolar interactions within the QD that cause significant anharmonicity in the spectrum of the nuclear spins. Strain-induced, inhomogeneous quadrupolar shifts also lead to a complete suppression of angular momentum exchange between the nuclear spin ensemble and its environment, resulting in nuclear spin relaxation times exceeding an hour. Remarkably, the position dependent axes of quadrupolar interactions render magnetic field sweeps inherently non-adiabatic, thereby causing an irreversible loss of nuclear spin polarization.Comment: 15 pages, 3 figure

Statistical modelling of growth using a mixed model with orthogonal polynomials

In statistical modelling, the effects of single-nucleotide polymorphisms (SNPs) are often regarded as time-independent. However, for traits recorded repeatedly, it is very interesting to investigate the behaviour of gene effects over time. In the analysis, simulated data from the 13th QTL-MAS Workshop (Wageningen, The Netherlands, April 2009) was used and the major goal was the modelling of genetic effects as time-dependent. For this purpose, a mixed model which describes each effect using the third-order Legendre orthogonal polynomials, in order to account for the correlation between consecutive measurements, is fitted. In this model, SNPs are modelled as fixed, while the environment is modelled as random effects. The maximum likelihood estimates of model parameters are obtained by the expectation–maximisation (EM) algorithm and the significance of the additive SNP effects is based on the likelihood ratio test, with p-values corrected for multiple testing. For each significant SNP, the percentage of the total variance contributed by this SNP is calculated. Moreover, by using a model which simultaneously incorporates effects of all of the SNPs, the prediction of future yields is conducted. As a result, 179 from the total of 453 SNPs covering 16 out of 18 true quantitative trait loci (QTL) were selected. The correlation between predicted and true breeding values was 0.73 for the data set with all SNPs and 0.84 for the data set with selected SNPs. In conclusion, we showed that a longitudinal approach allows for estimating changes of the variance contributed by each SNP over time and demonstrated that, for prediction, the pre-selection of SNPs plays an important role

Effectiveness of additional follow-up telephone counseling in a smoking cessation clinic in Beijing and predictors of quitting among Chinese male smokers

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