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Radiative lifetimes of 20 high-lying excited levels in neutral rhodium (Rh i) were measured using time-resolved laser-induced fluorescence technique, 17 of which are reported for the first time to our knowledge. These lifetimes were combined with theoretical branching fractions obtained from pseudo-relativistic Hartree–Fock calculations to deduce semi-empirical transition probabilities and oscillator strengths for 63 Rh i spectral lines.

As a low-cost marketing model, telemarketing has always been the most important channel for banks to promote wealth management products. Traditional telemarketing has not only brought intrusiveness to many telephone access customers, but also a waste of resources for the bank itself. In order to improve the success rate of bank telemarketing, it is necessary to predict in advance which customers are most likely to purchase the wealth management product, so as to achieve precision marketing. Aiming at the complex high-dimensional nonlinear characteristics of the factors affecting the success rate of telemarketing, a t-SNE (t-distributed stochastic neighbor embedding) feature extraction method, and then take the extracted low-dimensional features as input, use nonlinear support vector machine (SVM) for training and prediction. The empirical results show that the bank phone based on t-SNE-SVM proposed in this paper. The marketing prediction model has good learning ability and generalization ability, which can provide certain decision-making reference for banks and other industries to achieve precision marketing.

Radiative lifetimes of 19 levels in Re I were measured using the time-resolved laser-induced fluorescence method. As far as we know, 15 results are reported for the first time. By combining the experimental lifetimes determined from the present work with theoretical branching fractions obtained by a pseudo-relativistic Hartree–Fock model including core-polarization contributions, a new set of semi-empirical transition probabilities and oscillator strengths for 47 Re I lines from 18 newly measured levels were derived.

Radiative lifetimes of five levels in Be I lying in the energy range 64,506.45–71,160.52 cm−1 were measured by the time-resolved laser-induced fluorescence technique. These new data, together with previously measured radiative lifetimes and two reliable calculated lifetimes, were combined with branching fractions obtained from pseudo-relativistic Hartree–Fock calculations to deduce semi-empirical transition probabilities and oscillator strengths for 90 Be I spectral lines involving upper levels ranging from 42,565.35 to 72,251.27 cm−1.

In this paper, we derive an analytical solution of linearly chirped Airy beams (CAB) propagating in strongly nonlocal media with focusing and defocusing nonlinearity. Our analytical results show the periodic evolution pattern of CAB supported by strongly nonlocal focusing nonlinearity is made to be gradually reshaped each other between Airy distribution and conventional standard Gaussian distribution. Meanwhile, we further disclose how initial chirp affects the periodic evolution of optical beam. It is found that we can change ballistic trajectory gradually from conventional parabolic to trigonometric shapes through increasing initial chirp; however the corresponding period is only determined by the degree of nonlocality but independent on the former. Moreover, another interesting property is that initial chirp will lead to a positive or negative transverse displacement of the resulting Gaussian distribution depending on the direction of input beam, but does not affect its shape and longitudinal location. On the other hand, for defocusing nonlinearity, CAB is found to exhibit the conventional nonperiodic self-accelerating behavior, which direction is decided by the initial chirp. Our analytical results agree with the existing results and can be confirmed by numerical prediction.

This paper presents cavitation action of the oil film seal with downstream-pumping spiral groove and effect of cavitation on the hydrodynamic performances. A hydrodynamic lubricant model with JFO cavitation boundary is established and the visual experiments of cavitation under different working conditions are conducted, the cavitation evolution acquired and the theoretical and experimental leakage compared. Results show that higher speed effectively promotes cavitation but higher oil pressure inhibits it. Both increasing groove number and decreasing groove angle with limits reduce the cavitation zone but effects of them on the cavitation boundaries are different. By comparison, the cavitation occurrence plays an active role in the reduction of film thickness, improvement of oil film stiffness and the reduction of leakage.

In this paper, we propose a new family of circular Airy beam (CAB) through introducing a cone angle. We investigate the autofocusing properties of such conical circular Airy beam (CCAB) both analytically and numerically, particularly focusing on the novel behaviors different from the case of the conventional CAB. Under the action of positive cone angles, the autofocusing effect of CCAB is greatly strengthened, and the focal length is remarkably reduced, as compared to the case of conventional CAB. On the other hand, the autofocusing effect may be weakened or even completely eliminated, and the focal length is largely extended under the action of negative cone angles. Therefore, such dramatic enhancement or suppression of abruptly focus can be effectively controlled through adjusting the cone angle. The novel autofocusing properties will make CCAB more powerful in various applied fields including optical trapping and particle manipulation.

In this paper, we investigate the behavior of modulation instability(MI) induced by nonlinear diffraction (NLD) resulting from the vectoral effect in metamaterials with simultaneous Kerr-type electric and magnetic nonlinearity, trying to unfold some novel properties different from those in conventional positive-index media(CM). First, NLD in metamaterials differs from CM mainly in that its value is able to be positive or negative, which provides greater flexibility for us to control the dynamical behavior of MI. Then, we further show that NLD exerts strong influence upon the MI scenario for both defocusing and focusing nonlinear cases, depending on its magnitude and sign. Moreover, we demonstrate NLD can make MI possible even in metamaterials with focusing nonlinearity of negative diffraction case. Finally, we observe NLD under certain limits can open up a new modulation window with an infinite modulation frequency range unseen in conventional MI scenario. Our results denote that NLD in metamaterials can provide us a more powerful strategy to engineer the behavior of MI, as compared with the counterpart in CM.

The dynamic response of the spiral groove liquid film seal to three types of impact are studied by developing a three-DOF dynamic model which takes average flow model, cavitation effect, squeeze effect and face contact into account. A Gaussian pulse function is first applied to simulate the impact to the seal. Results indicate that the seal can maintain hydrodynamic lubrication regime to avoid significant face contact regardless of the impact type. The pressure variation impact does not necessarily induce leakage due to the dramatically narrowed sealing gap. The shaft drifting and bending impact conditions can bring about leakage risk, but the symptomatic flow rate induced by the former is much heavier than that by the latter at the representive moment.

Background Diabetes mellitus characterized by hyperglycemia as a result of insufficient production of or reduced sensitivity to insulin poses a growing threat to the health of people. It is a heterogeneous disorder with multiple etiologies consisting of type 1 diabetes, type 2 diabetes, gestational diabetes and so on. Diabetes-associated protein/gene prediction is a key step to understand the cellular mechanisms related to diabetes mellitus. Compared with experimental methods, computational predictions of candidate proteins/genes are cheaper and more effortless. Protein-protein interaction (PPI) data produced by the high-throughput technology have been used to prioritize candidate disease genes/proteins. However, the false interactions in the PPI data seriously hurt computational methods performance. In order to address that particular question, new methods are developed to identify candidate disease genes/proteins via integrating biological data from other sources. Results In this study, a new framework called PDMG is proposed to predict candidate disease genes/proteins. First, the weighted networks are building in terms of the combination of the subcellular localization information and PPI data. To form the weighted networks, the importance of each compartment is evaluated based on the number of interacted proteins in this compartment. This is because the very different roles played by different compartments in cell activities. Besides, some compartments are more important than others. Based on the evaluated compartments, the interactions between proteins are scored and the weighted PPI networks are constructed. Second, the known disease genes are extracted from OMIM database as the seed genes to expand disease-specific networks based on the weighted networks. Third, the weighted values between a protein and its neighbors in the disease-related networks are added together and the sum is as the score of the protein. Last but not least, the proteins are ranked based on descending order of their scores. The candidate proteins in the top are considered to be associated with the diseases and are potential disease-related proteins. Various types of data, such as type 2 diabetes-associated genes, subcellular localizations and protein interactions, are used to test PDMG method. Conclusions The results show that the proteins/genes functionally exerting a direct influence over diabetes are consistently placed at the head of the queue. PDMG expands and ranks 445 candidate proteins from the seed set including original 27 type 2 diabetes proteins. Out of the top 27 proteins, 14 proteins are the real type 2 diabetes proteins. The literature extracted from the PubMed database has proved that, out of 13 novel proteins, 8 proteins are associated with diabetes.

In order to compare different genome sequences, an alignment-free method has proposed. First, we presented a new graphical representation of DNA sequences without degeneracy, which is conducive to intuitive comparison of sequences. Then, a new numerical characterization based on the representation was introduced to quantitatively depict the intrinsic nature of genome sequences, and considered as a 10-dimensional vector in the mathematical space. Alignment-free comparison of sequences was performed by computing the distances between vectors of the corresponding numerical characterizations, which define the evolutionary relationship. Two data sets of DNA sequences were constructed to assess the performance on sequence comparison. The results illustrate well validity of the method. The new numerical characterization provides a powerful tool for genome comparison.

By assigning to four kinds of basic nucleotide A, T, G and C, respectively, four different two-component vectors, in which the first elements are constant (equal to 1) and the second elements are different from each other, we presented a 2D graphical representation of DNA primary sequences, which is mathematically proven to be not any circuit and associated with DNA sequences in a one-to-one manner and whose advantage is that it helps in identifying major difference among similar DNA sequences. Making use of the presented graphical representation, we analyzed DNA mutations between sequences.

To investigate the structural abnormalities of brain in patients with antisocial personality disorder (ASPD) but without alcoholism and drug abuse.Volunteers from Hunan Reformatory (n=36) and the matched healthy subjects (n=26) were examined by high-spatial resolution magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Voxel-based morphometry and fractional anisotropy (FA) maps were generated for each subject to reveal structural abnormalities in patients with ASPD.Compared with the healthy controls, ASPD patients showed significantly higher gray matter volumes in the inferior parietal lobule (P≤0.001, uncorrected), white matter volumes in the precuneus (P≤0.001, uncorrected), FA in the left lingual gyrus, bilateral precuneus, right superior frontal gyrus and right middle temporal gyrus (P≤0.01, uncorrected).Our results revealed the abnormal neuroanatomical features in ASPD patients, which might be related to the external behavioral traits in ASPD patients.

The additional dispersive magnetic permeability in metamaterials (MMs) described by the Drude model is able to generate the anomalous self-steepening (SS) effect which can be positive, negative even zero. This provides more great flexibility for us to control ultrashort pulse propagation, when compared with the corresponding case in naturally positive-index materials (PIMs). In this paper, we theoretically investigate the self-accelerating control of Airy pulse through such anomalous SS effect in MMs with a cubic nonlinearity. The emphasis is given to the counterintuitive dynamical behavior different from those in PIMs. It is shown that positive SS in MMs acts to promote the self-acceleration of such pulse and the corresponding spectral features exhibits a broad redshifted behaviors, as it does in PIMs; while the negative SS gives rise to the appearance of the opposite situation. That is to say, the self-acceleration of Airy pulse will be delayed through broadening the spectrum toward blue side. Meanwhile, the effect of the specific truncation coefficient imposed on Airy pulses in MMs also be discussed under the roles of positive and negative SS, respectively. Our findings show that the SS effect in MMs can provide a more powerful tool in controlling the self-accelerating of Airy pulse when compared with the corresponding case in PIMs.

The false positive rate and false negative rate in the biological data have a negative impact on prediction of essential proteins by computational methods. In this work, a new method called CNC is developed to detect essential proteins. First, subcellular localisation information is used to evaluate the importance of interactions in the protein networks and the interactions are weighted for the first time. Meanwhile the edge clustering coefficients between the interacting proteins are calculated and serve as the second weighted value. Next, the two weighted technologies are integrated to construct a new weighted protein networks. Finally, each protein in the PPI networks is scored in terms of the weighted interactions between the protein and its direct neighbours. The results show that the new centrality measure CNC is more effective in discovering essential protein compared with other familiar methods.

We denoted the four nucleotides, A, T, G and C, as four two-component vectors, and illustrated a nucleotide sequence as a curve in the 2D space by concatenating the vectors representing the nucleotides in the sequence. We studied the similarities among multiple nucleotide sequences by comparing their corresponding curves, with the beta-globin genes from 7 species as an example.

A starburst molecule (T) with triphenylamine (TPA) and benzothiodiazole (BTD) as constructing units was synthesized via two step Heck coupling reaction. As compared with its linear counterpart, it shows better solubility and amorphous film-forming ability. Spectroscopic properties show that it emits red light with emission peak at 651 nm in CH2Cl2. The red light emitting arises from the intramoleculasr charger transfer state. White light emitting diode (WLED) was fabricated with the starburst molecule as red light emitting composite. The luminance and efficiency maximum was 3960 cd/m2, and 1.22 cd/A for the WLED device with only 0.05%.(W/W) doping content of the light emitting composite. The high performance of WLED is attributed to the high chromorphore density and electron coupling effect of multi-branches. It is reasonable to conclude that starburst structure is superior to its linear and less branch counterparts in the fabrication of LED devices.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We investigate modulation instability (MI) in a nonlinear oppositely directed coupler with a quadratic nonlinearity, where one channel is made from a positive-index material (PIM) and another channel is fabricated from a negative-index material (NIM), trying to identify the different MI properties from those in a conventional parametric gap system with grating. Both the analytic continuous wave (CW) solutions and dispersion relation are obtained. By using standard linear instability we in detail discuss how the ratio of the backward to forward propagating wave’s power, the phase mismatch, and the coupled coefficient influence the dynamical behavior of MI. Large stable regions are found if the fundamental harmonics (FH) falls in the normal dispersion when compared to the case in the conventional Bragg grating with a quadratic nonlinearity where the CW solutions are unstable in most cases. In addition, we also observe the large stable regimes of the CW solutions even when the coupled strength for the second harmonics (SHs) is weaker than that of the FH. These findings suggest that the oppositely directed coupler with a NIM channel provides more ways to manipulate the MI and soliton.

Controllable and dispersive magnetic permeability in negative-index materials (NIMs) offers greatly enhanced design freedom to alter the linear and nonlinear properties. This makes it possible for us to control the propagation of ultrashort pulses at will. In this paper, we will investigate the self-focusing of ultrashort pulses associated with anomalous nonlinear self-steepening (SS) effect and anomalous space–time focus (linear SS) effect in bulk NIMs with a nonlinear electric polarization, trying to disclose some unusual behaviors different from those in naturally positive-index materials. It is found that negative SS acts to push the peak intensity toward the trailing edge of a pulse and the resulting spectrum exhibits a broad redshifted trail; however, positive SS leads to the occurrence of the opposite situation in both temporal and spectral domains, that is, the peak intensity will move toward the leading edge of the pulse by shifting the spectrum toward the blue side. In addition, compared with the case in positive-index materials (PIMs), another most notable property of NIMs is that, whether self-focusing of ultrashort pulses will occur at the leading or the trailing edge can be manipulated freely by engineering the SS effect by choosing the size of split-ring resonator circuit elements. Our analysis is performed by directly numerically solving nonlinear Schrodinger equations as well as by using the moment method, both showing consistent results. These findings demonstrate that NIMs can provide us unique opportunities unattainable in PIMs to manipulate ultrashort pulse propagation.