Components M2 Research Articles

Evolution of the Internet AS-level topology: From nodes and edges to components** Project supported by the National Natural Science Foundation of China (Grant No. 61671142).

Studying the topology of infrastructure communication networks (e.g., the Internet) has become a means to understand and develop complex systems. Therefore, investigating the evolution of Internet network topology might elucidate disciplines governing the dynamic process of complex systems. It may also contribute to a more intelligent communication network framework based on its autonomous behavior. In this paper, the Internet Autonomous Systems (ASes) topology from 1998 to 2013 was studied by deconstructing and analysing topological entities on three different scales (i.e., nodes, edges and 3 network components: single-edge component M1, binary component M2 and triangle component M3). The results indicate that: a) 95% of the Internet edges are internal edges (as opposed to external and boundary edges); b) the Internet network consists mainly of internal components, particularly M2 internal components; c) in most cases, a node initially connects with multiple nodes to form an M2 component to take part in the network; d) the Internet network evolves to lower entropy. Furthermore, we find that, as a complex system, the evolution of the Internet exhibits a behavioral series, which is similar to the biological phenomena concerned with the study on metabolism and replication. To the best of our knowledge, this is the first study of the evolution of the Internet network through analysis of dynamic features of its nodes, edges and components, and therefore our study represents an innovative approach to the subject.

Three-dimensional droplets of swirling superfluids

A new method for the creation of 3D solitary topological modes, corresponding to vortical droplets of a two-component dilute superfluid, is presented. We use the recently introduced system of nonlinearly coupled Gross-Pitaevskii equations, which include contact attraction between the components, and quartic repulsion stemming from the Lee-Huang-Yang correction to the mean-field energy. Self-trapped vortex tori, carrying the topological charges m1=m2=1 or m1=m2=2 in their components, are constructed by means of numerical and approximate analytical methods. The analysis reveals stability regions for the vortex droplets (in broad and relatively narrow parameter regions for m1=m2=1 and m1=m2=2, respectively). The results provide the first example of stable 3D self-trapped states with the double vorticity, in any physical setting. The stable modes are shaped as flat-top ones, with the space between the inner hole, induced by the vorticity, and the outer boundary filled by a nearly constant density. On the other hand, all modes with hidden vorticity, i.e., topological charges of the two components m1=-m2=1, are unstable. The stability of the droplets with m1=m2=1 against splitting (which is the main scenario of possible instability) is explained by estimating analytically the energy of the split and un-split states. The predicted results may be implemented, exploiting dilute quantum droplets in mixtures of Bose-Einstein condensates.

Joint Probability Distribution and the Minimum of a Set of Normalized Random Variables

Suppose that n types of components M1, M2… Mn are combined to form and integrated object I and suppose that y units of the integrated object are required to be formed. Assuming that not all components can be used in forming the integrated objects, let qj be the percentage of usable components of the jth type, a random variable having a probability density function fj(qj). Let wj be the normalized random variable obtained from qj by wj = qj/μj, where μj is the expected value of qj. Consider the random variable W=Min{wj, 1 ≤ j ≤ n}. This paper describes the joint probability distribution of the set of the normalized random variables and determines the probability distribution of the minimum W of this set. The expected value of W is key to determining the number of components needed to form the y integrated objects. A special case is presented where the percentages of usable components are uniformly distributed. The problem is applied to a production model.

Letter to the Editor: Joint Moments in the Joint Coordinate System, Euler or Dual Euler Basis

Letter to the Editor: Joint Moments in the Joint Coordinate System, Euler or Dual Euler Basis

Identification of metabolites of dalfampridine (4-aminopyridine) in dog and rat

Background:Dalfampridine (4-aminopyridine; 4-AP) is a potassium channel blocker available in the United States to improve walking in patients with multiple sclerosis as demonstrated by an increase in walking speed. Its pharmacokinetics have been evaluated in human studies but its metabolites are not well characterized. This study characterizes the metabolic profile of dalfampridine in two animal species that were used to support nonclinical toxicology evaluation.Methods:Metabolic profiling of single oral 14C-4-AP doses was performed in 12 adult male Sprague–Dawley rats. Similarly, metabolic profiling was performed in beagle dogs in two studies that administered 14C-4-AP by gastric intubation; the first study included six animals (three males, three females), and the second study included two animals (one male, one female). Blood and urine samples were evaluated using high performance liquid chromatography, thin layer chromatography, and radioanalysis (liquid scintillation counting), with further identification of components by gas chromatography/mass spectrometry.Results:Five radioactive components, M1–M5, were detected in rat plasma, although most of the radioactivity corresponded with unchanged 4-AP. Based on Rf values, M1 and M2 coseparated with reference standards of 3-hydroxy-4-AP and 4-AP, respectively. Additionally, components M1, M2, and M3 coseparated with the same components isolated from the urine of a dog dosed with 14C-4-AP and identified as 3-hydroxy-4-AP, 4-AP, and 3-hydroxy-4-AP sulfate, respectively; M4 and M5 could not be identified because of low concentrations. In dogs, most of the radioactivity was excreted within the first 24 hours as unchanged compound.Conclusions:Following oral dosing, 4-AP was rapidly absorbed in rats and dogs, with rapid excretion and almost complete urinary recovery in dogs. The primary metabolites in both animal models were 3-hydroxy-4-AP and 3-hydroxy-4-AP sulfate. Systemic clearance not accounted for by renal excretion of 4-AP may occur by liver metabolism by hydroxylation of 4-AP to 3-hydroxy-4-AP followed by sulfate conjugation to 3-hydroxy-4-AP sulfate.

Effect of circulating solution volume on codeposition process of two metals within porous electrode at high flow rate

The effect of the solution volume and deposition potential on the dynamics and final parameters of the deposition process was studied using a mathematical model of codeposition of the two metals within a one-dimensional flow porous electrode (PE). The initial PE characteristics, kinetic parameters of the overall polarization curve, and volume solution flow rate were fixed. It was found that a decrease in the solution volume at a high flow rate apart from the expected consequences (a decrease in the metal deposition rate in time and an increase in the time of the porous matrix filling by the deposit) results in a significant improvement of the uniformity of distribution of electropositive component M1 and a dramatic extension of the deposition region of electronegative component M2. The positive effect of a decrease in the solution volume is enhanced at an increase in the cathodic potential and the closing in of partial currents of the deposited metals. Eventually, these conditions provide simultaneously a high rate of metal recovery and maximum PE filling by the cathodic deposit.

Incommensurate Phases Induced by a Weak Electric Field

It is shown that an external electric field E3 (even if it is arbitrary weak) can induce an incommensurate phase in the crystal. The components M1 and M2 of the magnetic moment Mi are chosen as the order parameter components.

Spectral-decomposition techniques for the identification of periodic and anomalous phenomena in radon time-series

Abstract. Two hourly-sampled time-series of soil-gas radon concentrations of durations of the order of a year have been investigated for periodic and anomalous phenomena. These time-series have been recorded in locations having little or no routine human behaviour and thus are effectively free of significant anthropogenic influences. One measurement site, Sur-Frêtes, is located in the French Alps, with saturated soil conditions; the second site, Syabru-Bensi, is located in Nepal, in a river terrace with unsaturated soil conditions. In such conditions, periodic components with periods ranging from 8 h to 7 days are often weak and intermittent and therefore, even in the presence of stationary forcing, difficult to identify. Two spectral decomposition techniques, Empirical Mode Decomposition (EMD) and Singular Spectrum Analysis (SSA), have been applied to these time series and yield similar results. For Sur-Frêtes, weak diurnal and semi-diurnal components are observed with EMD, while SSA reveals only a diurnal component. In Syabru-Bensi, both EMD and SSA reveal a strong diurnal component and a weaker semi-diurnal component. Tidal components M1 and M2 are also suggested by EMD in Sur-Frêtes, while these frequencies are not observed in Syabru-Bensi. The development of such analytical techniques can help in characterising the multiple physical processes contributing to the surface and subsurface dynamics of soil gases.

The growth of iterates of multivariate generating functions

The vector-valued function m( ) of a p-vector has components m1( );m2( );:::;mp( ). For eachi, exp(mi( )) is the (multivariate) Laplace transform of a discrete measure concentrated on (0;1) p with only a nite number of atoms. The main objective is to give conditions for the functional iteratesm(n) ofm to grow like n for a suitable > 1. The initial stimulus was provided by results of Miller and O'Sullivan (1992) on enumeration issues in 'context free languages', results which can be improved using the theory devel- oped here. The theory also allow certain results in Jones (2004) on multitype branching to be proved under signicantly weaker conditions.

Photometric study of the eclipsing binary V1034 Sco

We present multi-colour Stromgren photometry of the eclipsing binary V1034 Sco in the galactic open cluster NGC 6231, providing for the first time a full coverage of the orbital period (P = 2.44 days) and a complete analysis of the orbit. This extensive new photometry was analyzed together with multiband spectroscopy and results in an improved ephemeris, photometric elements and absolute parameters of the components. The system is close, but clearly detached. The masses of the components M1 = 16.8 ± 0.5 Mand M2 = 9.4 ± 0.3 Mdo not correspond to the published spectral classification (O9III + B1III). The parameters of the components are consistent with the main-sequence luminosity class. We independently derive a distance modulus V0 − MV = 10.73 ± 0.02.

Effects of arousal and natural baroreceptor activation on the human muscle stretch reflex

The nociceptive flexion reflex is inhibited during systole; this inhibition may be due to increased baroreceptor stimulation. It is yet to be determined whether other spinal reflexes are similarly modulated across the cardiac cycle. There is also evidence that stretch and tendon reflexes are facilitated by increased arousal. This study investigated the effects of phase of the cardiac cycle and arousal on the muscle stretch reflex components M1, M2, and M3. Stretch reflexes were elicited in leg muscles at six intervals across the cardiac cycle during rest, number repetition, and mental arithmetic. Mental arithmetic provoked increased cardiovascular arousal and facilitated both M1 and M2 compared to rest and number repetition. The stretch reflex did not vary with the phase of the cardiac cycle. While the stretch reflex is susceptible to arousal, natural baroreceptor-mediated modulation across the cardiac cycle may be specific to nociception.

A planar Runge–Lenz vector

Following Dahl’s method an exact Runge–Lenz vector M with two components M1 and M2 is obtained as a constant of motion for a two particle system with charges e1 and e2 whose electromagnetic interaction is based on Chern–Simons electrodynamics. The Poisson bracket {M1,M2}≠Lz but is modified by the appearance of the product e1e2 as central charges.

Analysis of the first heart sound using the matching pursuit method.

It is acknowledged that the first heart sound S1 consists of two major, high-frequency components M1 and T1, corresponding, respectively, to the vibrations of the mitral and tricuspid valves and their surrounding tissues following valve closure in early systole. In this study, the matching pursuit (MP) method was used to decompose S1 into a series of time-frequency atoms. M1 and T1 were separated from the parameterised atoms of S1. The first two dominant frequencies of M1 were identified and used as features of a linear classifier to diagnose mitral valve abnormality. This method was applied to two sets of S1 data recorded from 15 patients with normal, and 15 patients with abnormal, bioprosthetic mitral valves, respectively. It was found that the two features exhibit significant differences between the normal and abnormal sets (p< 0.001). Using these two features, a correct classification of 93% was obtained. In addition, when the Wigner distribution of S1 was calculated from the decomposed atoms and compared with a spectrogram, the MP method provided better results. The study demonstrates that the MP method may be a promising technique for heart sound analysis.

Spectroscopic and photometric observations of the short-period RS CVn star RT And

Spectroscopic observations in the range 6500{6700 A and BVRI photometry of the eclipsing short- period RS CVn-star RT And are presented. We determined K1 = 130 km s 1 and K2 = 175: 8k m s 1 by measurement of the double proles of the lines H and FeI 6678, and obtained the mass ratio q =0 :74 and masses of the star components M1 =1 :23 M and M2 =0 :91 M. It was established that the emission activity of RT And is associated with its secondary component. The relative contribution of the secondary star is stronger in the FeI 6678 line than in H. A strong emission feature between the two proles of FeI 6678 at phase 0.73 was detected that is probably due to the appearance of extended emitting structure. The multicolor light curve of RT And is tted by two cool spots on the primary star with equal sizes 21 and temperatures 4980 K and located at middle latitudes and longitudes symmetrical to the line connecting the star centers. Both spectral and photometric data lead to the conclusion that the secondary star of RT And is oversized for its mass.

Long-latency component of the stretch reflex in human muscle is not mediated by intramuscular stretch receptors.

Reflex responses to mechanical stimulation of muscle (brief imposed movement) were investigated. Reflexes were elicited in the forefinger, recording from the first dorsal interosseous (FDI), and in the foot, recording from soleus. These responses typically consisted of a short-latency component (M1) and a long-latency component (M2) at 33 ms and 53 ms, respectively, after the stimulus in the case of FDI, and 37 ms and 68 ms, respectively, in soleus upon stimulation of the sole of the foot. Normally, when a muscle is stretched by a mechanical stimulus (either naturally or by an experimentally imposed movement), both skin receptors and muscle stretch receptors are activated. It is possible, however, to devise stimulation parameters where this is not the case. Fixating the finger with plasticine enables the effects of skin stimulation to be studied without stretching the FDI muscle. On the other hand, tapping a long tendon allows muscle stretch receptors to be activated without involving skin or subcutaneous structures. Component M1 was always abolished by finger fixation in 40 trials on 10 subjects, with M2 being essentially unchanged in latency, duration, or amplitude. Reflex responses were obtained in soleus muscle in nine experiments by prodding the sole of the foot (thereby stimulating both skin and muscle stretch receptors). Alternatively, the tendo achilles was prodded (which solely activates stretch receptors in the muscle). In the former, M1 and M2 were generated. In the latter, only M1 was produced. It is concluded that the long-latency component of the stretch reflex, M2, originates in skin and/or subcutaneous nerve terminals and that no part of M2 originates in muscle stretch receptors.

Excitonically Induced Defect Annihilation in Solid Krypton

by two Gaussians: low energy subband M1 and high energy one M2 [5]. These subbands with FWHM of 0.44 eV and 0.41 eV are situated at 8.44 eV and 8.64 eV. The subband M2 is due to the exciton self-trapping in the regular lattice while the component M1 is due to the trapping at the lattice defects. The dose dependence of these components under irradiation reflects the changes in defect concentration. In the high-quality crystals, DFIET causes an increase of M1 relative to M2 with increasing dose [5], and electronically induced defect annihilation is hidden. To reveal the process of annihilation, the concentration of initial defects should be high enough. We have succeeded in detecting the defect annihilation with a sample which was grown by fast condensation at Ta 55 K and fast cooling to Ta 6 K. Fig. 1 shows the time evolution of the M-band under irradiation. The intensity of the ‘‘defect” M1-subband decreases with time of irradiation whereas M2-subband grows in intensity. This redistribution of the intensities between the subbands in

Semiparametric additive indices for binary response and generalized additive models

Models are studied where the response Y andcovariates X,T are assumed to fulfill E(Y | X;T) =G{XTbeta + alpha + m1(T1 ) + ...+ md(Td) }. Here G is a known (link) function,beta is an unknown parameter, and m1, ..., md areunknown functions. In particular, we consider additive binary response models where the response Y is binary. In these models, given X and T, the response Y has a Bernoulli distribution with parameter G{ XTbeta + alpha + m1(T1 ) + ... + md(Td) }. The paper discusses estimation of beta and m1, ... , md. Procedures are proposed for testing linearity of the additive components m1, ... , md. Furthermore, bootstrap uniform confidence intervals for the additive components are introduced. The practical performance of the proposed methods is discussed in simulations and in two economic applications.

An Intestinal Bacterial Metabolite of Ginseng Protopanaxadiol Saponins Has the Ability to Induce Apoptosis in Tumor Cells

Our previous study demonstrated that thein vivoanti-metastatic effect induced by oral administration of ginseng protopanaxadiol saponins was mediated by their metabolic component M1, and that the growth, invasion and migration of tumor cells were inhibited by M1 but not by ginsenosides. Here we investigated the inhibitory mechanism of M1 on the growth of tumor cells. M1 inhibited the proliferation of B16-BL6 mouse melanoma cells in a time- and dose-dependent manner, with accompanying morphological changes at the concentration of 20 μM. In addition, at 40 μM M1 induced apoptotic cell death within 24 h. Fluorescence microscopy revealed that dansyl M1 entered the cytosol and quickly reached the nuclei (approximately 15 min). Western blot analysis revealed that M1 rapidly up-regulated the expression of p27Kip1, but down-regulated the expression of c-Myc and cyclin D1 in a time-dependent manner. Thus, the regulation of apoptosis-related proteins by M1 is responsible for the induction of apoptotic cell death, and this probably leads to the anti-metastatic activityin vivo.

Studies on the galactomannan-degrading enzymes produced bySporotrichum cellulophilum

Extracellular mannanase activity produced bySporotrichum cellulophilum was purified into two components using acetone precipitation, SP-Sephadex C50 ion exchange chromatography and preparative polyacrylamide gel electrophoresis. The purified mannanse components, M1 and M2, had molecular weights of 108 000–112 000 and 32 200–36 000 respectively. Component M1 was shown to contain 2 subunits having molecular weights of 62 000 and 50 000. M1 and M2 had similar pH-activity profiles with pH optima of 5.5 and 6.0 respectively. M1 was more thermostable than M2: half lives of the enzymes at 70°C were 30 and 9 min for M1 and M2 respectively.

High-performance liquid chromatographic determination of virginiamycin in Stafac, premixes and animal feeds

A reversed-phase high-performance liquid chromatographic method with ultraviolet detection is described for the simultaneous determination of the virginiamycin components M1 and S1 in Stafac, premixes and feeds. The concentrations and ratios of the components determine a synergistic activity, which is calculated. Virginiamycin is extracted from Stafac using acetonitrile–water (1 + 1), from feeds using dichloromethane and from premixes using either of the extraction solutions. The acetonitrile extracts are injected directly, the dichloromethane extracts are cleaned by passing them through a silica solid-phase extraction cartridge, followed by two consecutive washings; virginiamycin is desorbed with acetonitrile–water (1 + 1). The peak area response is linear for virginiamycin activities of between 5 and 50 µg ml–1. The detection limit in feeds (both pellets and mash) is 5 ppm. The method is specific, accurate and has a good repeatability. It complements well the existing microbiological methods.