Determination of the dynamic geotechnical properties and seismic wave velocities serves as essential inputs for a foundation design cognizant of seismic site response and rock strength. This study evaluates competent zones for construction at Ahmadu Bello University Zaria, Phase II site. Four shallow seismic refraction profiles were carried out using the ABEM Terraloc Pro seismograph. Compressional (P) and shear (S) waves were acquired and the time-term technique, which is a combination of linear least squares and delay time analysis to invert the first arrivals for a velocity section and then to tomography section was adopted. These sections were correlated with a borehole report and a good matching was observed. The result shows that the area consists of three subsurface layers; an overburden with average thickness of about 10.5 m and P- and S-wave velocities (velocities) of about 550 m/s and 345 m/s respectively, the weathered basement with an average thickness of 12.5 m and velocities of 950 m/s and 550 m/s respectively, while the fresh basement was found at a depth of about 24 m with velocities of 1250 m/s and 680 m/s respectively. The Concentration Index, Material Index, Poisson’s Ratio, and Stress Ratio were calculated to be in the range of 4.869 to 6.128, -0.032 to 0.312, 0.172 to 0.258, and 0.267 to 0.346 respectively in the study area. The seismic velocity values, engineering consolidation, and strength parameters showed that the subsurface soil/rock at the eastern parts of the study area is characterized by less competent soil/rock quality while the western parts are characterized by more competent soil/rock quality. Hence, the western and north-western parts are more preferable for the foundation of structures to be erected.

Non-destructive exploration using elastic waves has been widely used to characterize rock mass properties. Wave propagation in jointed rock masses is significantly governed by the characteristics and orientation of discontinuities. The relationship between spatial heterogeneity (i.e., joint spacing) and wavelength for elastic waves propagating through jointed rock masses have been investigated previously. Discontinuous rock masses can be considered as an equivalent continuum material when the wavelength of the propagating elastic wave exceeds the spatial heterogeneity. However, it is unclear how stress-dependent long-wavelength elastic waves propagate through a repetitive rock-joint system with multiple joints. A preliminary numerical simulation was performed in in this study to investigate long-wavelength elastic wave propagation in regularly jointed rock masses using the three-dimensional distinct element code program. First, experimental studies using the quasi-static resonant column (QSRC) testing device are performed on regularly jointed disc column specimens for three different materials (acetal, aluminum, and gneiss). The P- and S-wave velocities of the specimens are obtained under various normal stress levels. The normal and shear joint stiffness are calculated from the experimental results using an equivalent continuum model and used as input parameters for numerical analysis. The spatial and temporal sizes are carefully selected to guarantee a stable numerical simulation. Based on the calibrated jointed rock model, the numerical and experimental results are compared.

Correlation of near surface fractures with seismic radial anisotropy: An approach for near surface fracture identification

Landfills will continue to provide optimal solutions for residual waste disposal at most locations in Australia. Selected case studies, demonstrate recent applications of surface and borehole geophysical technologies at some existing industrial and domestic landfills to address a range of geotechnical and environmental issues. Electromagnetic, P and S-wave seismic, resistivity, magnetic and gravity methods provide responses that locate the landfill margins and their base, leachate pathways and provide volume estimates for dense materials in the waste. Geophysical technologies are best used at the early stages of the investigations where they provide information that is not easily obtained with other invasive technologies. While these technologies are often cost-effective they do not reliably discriminate different buried wastes, subtle contamination sources nor are they generally capable of sensing groundwater contamination at human risk levels. Regardless of these limitations, geophysics will continue to be applied at Australian landfills and fill sites.

A rock physics model for typical oil company AvO modelling and inversion applications would ideally possess the following attributes: 1) a sound physical basis; 2) as few free variables as possible; and 3) wo uld predict measured P- and S-wave velocities for any lithology, porosity, pressure, temperature, pore-shape and pore-fluid. A formulation based on the doctoral research of Y. F. Sun into the dynamical theory of fractured porous media strikes a practical balance between these attributes, which are to some extent conflicting.

We first report on the Love wave tomography of China based on ambient noise cross-correlations. We used 3 years of continuous waveform data recorded by 206 broadband seismic stations on the Chinese Mainland and 36 neighboring global stations and obtained Love wave empirical Green’s functions from cross-correlations of the horizontal components. The Love wave group velocity dispersion measurements were used to construct dispersion maps of 8- to 40-s periods, which were then inverted to obtain a three-dimensional horizontally polarized S-wave (SH) velocity structure. The resolution was approximately 4° × 4° and 8° × 8° for eastern and western China, respectively, and extended to a depth of approximately 50 km. The SH model was generally consistent with a previously published vertically polarized S-wave (SV) model and showed large-scale features that were consistent with geological units, such as the major basins and changes in the crustal thickness across the north-south gravity lineament. The SH and SV models also showed substantial differences, which were used to examine the subsurface radial anisotropy. We define the radial anisotropy parameter as \begin{document}$\psi = 2\left( {{V_{\rm SH}} - {V_{\rm SV}}} \right)/\left( {{V_{\rm SH}} + {V_{\rm SV}}} \right)$\end{document} . At a shallow depth, we observed significant radial anisotropy under major basins, which may be related to thick sedimentary layers. At the mid to lower crust, most of the Chinese continent showed strong positive radial anisotropy (SH > SV). Central and southern Tibet showed strong positive anisotropy, whereas the radial anisotropy was relatively weak at the northern and eastern margins, which suggests a change in deformation style from the plateau interior to its margins. The North China craton showed prominent positive radial anisotropy, which may be related to decratonization and strong extension since the Mesozoic Era. Love waves are less well retrieved than Rayleigh waves from ambient noise cross-correlations. Increasing the duration of the cross-correlation data beyond 4 to 8 years may not aid in retrieving Love waves of longer periods, for which improved methods need to be explored.

Water affects the mechanical properties of coal and stress wave propagation. To comprehensively investigate the effect of water content on the properties of coal, laboratory tests including X-Ray Diffraction (XRD) analysis, P-wave test, S-wave test, static and dynamic compression test with different water contents were conducted. The compressive strength, elastic modulus and failure strain and their mechanism of coal specimen under coupled static-dynamic load with the increased water content were observed. Meanwhile, energy transmission and dissipation characteristics of a stress wave in coal specimens with different water contents under dynamic load and its relation with the failure features, such as fragmentation and fractal dimension, of coal was analyzed. Furthermore, the dynamic interpretation of water infusion to prevent coal burst based on water infusion model of coal seam roadway was provided.

In this article, we assign Omega _c(3000), Omega _c(3050), Omega _c(3066), Omega _c(3090) and Omega _c(3119) to the P-wave baryon states with J^P={frac{1}{2}}^-, {frac{1}{2}}^-, {frac{3}{2}}^-, {frac{3}{2}}^- and {frac{5}{2}}^-, respectively, and study them with the QCD sum rules by introducing an explicit relative P-wave between the two s quarks. The predictions support assigning Omega _c(3050), Omega _c(3066), Omega _c(3090) and Omega _c(3119) to the P-wave baryon states with J^P={frac{1}{2}}^-, {frac{3}{2}}^-, {frac{3}{2}}^- and {frac{5}{2}}^-, respectively, where the two s quarks are in relative P-wave, while Omega _c(3000) can be assigned to the P-wave baryon state with J^{P}={frac{1}{2}}^-, where the two s quarks are in relative S-wave.

Erratum:<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>s</mml:mi></mml:math>-wave scattering lengths of the strongly dipolar bosons<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">Dy</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>162</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">Dy</mml:mi><mml:mprescripts/><mml:none/><mml:mrow><mml:mn>164</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math>[Phys. Rev. A<b>92</b>, 022703 (2015)

En este trabajo aplicamos el metodo de Interferometria Sismica (IS) para determinar la variacion lateral en la distribucion de la velocidad de onda S (Vs) en la estructura de un macizo rocoso que contiene un talud localizado en el circuito Joaquin Claussell de la 3a Seccion del Bosque de Chapultepec. Estudios geologicos y de geotecnia muestran la presencia de un estrato pumicitico, que sobreyace a materiales semi permeables; el cual es susceptible a fallamiento y provocar deslizamientos, debido al estado de fracturamiento y el aporte de agua durante la epoca de lluvias, factores comunmente asociados a deslizamientos en la zona poniente de la Ciudad Mexico. A fin de mostrar la aplicabilidad del metodo de IS para cuantificar las propiedades elasticas y su distribucion en los estratos que conforman el cuerpo del talud, se generaron funciones de correlacion cruzada entre 4560 pares de receptores en un arreglo irregular de 96 geofonos verticales. Mediante el uso de las variaciones temporales del maximo pulso de correlacion en funcion de la frecuencia (4 a 24 Hz), construimos imagenes a partir de la tomografia de Vs relativa. Encontramos que valores de Vs cercanos a 300 m/s se relacionan con los estratos de pomez, los cuales se encuentran principalmente alojados hacia la cara del talud y en su parte topografica mas baja. La velocidad en estos materiales contrasta notablemente con la del estrato subyacente de valores superiores a 1000 m/s. Los valores de Vs y la geometria del estrato susceptible a deslizarse fueron corroborados por dos lineas de refraccion sismica. Los resultados de este estudio, sugieren que el metodo de IS es apropiado, debido a su caracter no invasivo ni destructivo, para analizar este tipo de riesgos geologicos asociados con la estabilidad de taludes

Background: In patients with severe aortic stenosis (AS), left ventricular systolic longitudinal function (SLF) is impaired despitenormal ejection fraction (EF). However, similarly to other shortening indexes, SLF depends on afterload and its relationshipwith contractility has not been thoroughly studied.Objective: The aim of this study was to evaluate SLF alterations and their relationship with afterload and myocardial contractilityin patients with severe AS.Methods: One hundred and one patients with severe AS (AVA <1 cm2) and 63 normal control subjects were studied withDoppler echocardiography. Left ventricular systolic longitudinal function was evaluated by lateral mitral annulus systolicdisplacement (MASD) and peak S wave velocity (tissue Doppler imaging). Contractility was assessed by the midwall fractionalshortening (mFS)–end-systolic stress (ESS) relationship in control subjects. Contractility level (CL) was defined as measuredmFS minus predicted mFS for a defined ESS value.Results: Lateral mitral annulus systolic displacement and S wave correlated directly with shortening indexes as EF and mFSand inversely with afterload indexes as ESS. There was no correlation between SLF and CL. In the multivariate analysisESS and EF were predictors of SLF.Conclusions: In patients with severe AS, SLF correlated inversely with afterload. The presence of decreased MASD or S wavewas not associated with abnormal left ventricular contractility.

The compression wave(P-wave) and shear wave(S-wave) in dry sand are measured simultaneously by a bender-extender element incorporated in a resonant column apparatus. The characteristics of the output P-wave and S-wave signals are analyzed; and the effects of the input signal frequency, soil density and effective confining pressure on the signal characteristics are investigated. According to the wave propagation theory and measured S-wave and P-wave velocity, the elastic properties of the dry sand are calculated, including shear modulus, constrained modulus and Poisson's ratio. The results indicate that to some extend the frequency of the output signal increases with increasing input frequency, soil density and effective confining pressure. Compared with S-wave, it is easier to determine the P-wave travel time and thus the wave velocity. The elastic modulus of the soil increases with increasing density and effective confining pressure, especially the shear modulus. The Poisson's ratio decreases with increasing density and confining pressure, instead of a constant. Attempt is also made to estimate the Poisson's ratio based on shear modulus considering the convenience of application in the practical engineering.

Nonlinear inversion based on Metropolis sampling algorithm is formulated in the Bayesian framework. As one kind of Monte Carl non-linear inversions, it can effectively integrate high frequency information of well logging data, and obtain inversion results with a higher resolution. Firstly, we get the priori information through fast Fourier transform moving average (FFT-MA) and gradual deformation method (GDM). Second, we structure likelihood function. Then we apply Metropolis algorithm in order to obtain an exhaustive characterization of the posteriori probability density. FFT-MA is a kind of efficient simulation method. Combined with GDM, it can constantly modify reservoir model and keep the spatial structure unchanged until it matches the observed seismic data. According to the model trial and real data processing, we can conclude that nonlinear inversion based on Metropolis sampling algorithm provide reasonable elastic parameter information, especially it improves the resolution of P-wave velocity. Even when the signal noise ratio (SNR) is relatively low, it can still show reasonable elastic parameter information, which proves the effectiveness of the proposed method. The inversion resolution of P-wave and S-wave impedances is higher than elastic parameters inversion if we do not consider the noise. ©, 2015, Science Press. All right reserved.

Jakarta is located on a thick sedimentary layer that potentially has a very high seismic wave amplification. However, the available information concerning the subsurface model and bedrock depth is insufficient for a seismic hazard analysis. In this study, a microtremor array method was applied to estimate the geometry and S-wave velocity of the sedimentary layer. The spatial autocorrelation (SPAC) method was applied to estimate the dispersion curve, while the S-wave velocity was estimated using a genetic algorithm approach. The analysis of the 1D and 2D S-wave velocity profiles shows that along a north-south line, the sedimentary layer is thicker towards the north. It has a positive correlation with a geological cross section derived from a borehole down to a depth of about 300 m. The SPT data from the BMKG site were used to verify the 1D S-wave velocity profile. They show a good agreement. The microtremor analysis reached the engineering bedrock in a range from 359 to 608 m as depicted by a cross section in the north-south direction. The site class was also estimated at each site, based on the average S-wave velocity until 30 m depth. The sites UI to ISTN belong to class D (medium soil), while BMKG and ANCL belong to class E (soft soil).

Objective To explore the correlation between wide QRS of transesophageal atrial pacing （TEAP） and implicit ventricular pre-excitation.Methods 77 patients tested by TEAP were divided into two groups according to the ECG results .45 patients in group Ⅰhad normal electrocardiogram .32 patients in group Ⅱhad ven-tricular pre-excitation.In group Ⅰ,TEAP results showed that electric pulse wave （S wave） was followed by intermit-tent or continuous wide QRS complex .At the same time , the results of group Ⅰ were compared with the results of groupⅡ.Results （1）The patients of group Ⅰwere excluded the presence of concealed accessory pathway by intra-cavitary electrocardiographic test,among them 20 patients （group ⅠA） were ventricular pacing,the test results dis-played that S wave was followed by wide QRS complex exhibiting a pattern of right bundle branch block （ RBBB） ,SR interval was 0 s;SR intervals of 25 patients （groupⅠB） were not fixed,SR interval was （0.07 ±0.01）s,S wave had no concern with QRS wave ,the wide QRS complex was premature ventricular contraction ,QRS wave shapes were dif-ferent according to the different sites of pacing origin .（2）In groupⅡ,the test results displayed that S wave was close-ly followed by the atrial depolarization wave P ,and there was a wide QRS complex with pre-excitation wave at the be-ginning after a atrioventricular conduction time shorter than normal ,SR interval was fixed ,SR interval was （0.08 ±0. 03）s,at the same time,different parts of accessory pathway QRS complex had different morphological characteristics . （3） SR interval of ⅠA group compared with groupⅠB and groupⅡ,the differences were statistically significant （ t=2.97,3.02,all P〈0.05）;SR interval had no statistically significant difference between group ⅠB and groupⅡ（t=2.66,P〉0.05）.Conclusion When TEAP displaying pacing wide QRS complex ,in order to avoid bringing misdiag-nosis,TEAP results should be analyzed comprehensively rather than blindly believing that the reason was concealed accessory pathway . Key words: Echocardiography,transesophageal; Heart ventricles; Pre-excitation syndromes

Objective To evaluate the morphologic and hemodynamic changes of fetal superior vena cava (SVC) with gestational age during the second and third trimester by ultrasound.Methods Two hundred normal singleton pregnancies between 20 and 40 weeks of gestation from our out-patient department were included.They were divided into 5 groups (20-24 weeks,24 +1-28 weeks,28 + 1-32 weeks,32+1-36 weeks,36+t-40 weeks) with 40 cases for each group.SVC diameter and length were measured by two-dimensional ultrasound at approximately 0.5-1.0 cm away from the right atrium-SVC junction along the longitudinal axis of SVC.SVC Doppler flow spectra were obtained and the characteristics of the spectra changes with gestational age were observed.Results Both the SVC diameter and displayable length were closely correlated with gestational age (r =0.908,r =0.585,P ＜0.01 respectively).Doppler interrogation of the SVC revealed the waveform was composed of S-wave,D-wave,and a small,reversed Awave in all fetuses.The velocity of S,D and A waves increased significantly after 28 weeks gestational age (P ＜ 0.05).Conclusions SVC diameter and displayable length have close correlation with gestational age,SVC flow velocities changes regularly with gestational age. Key words: Ultrasonography, Doppler ; Fetus ; Vena cava, superior

Abstract. We calculated the seismic properties of 47 mantle xenoliths from 9 kimberlitic pipes in the Kaapvaal craton based on their modal composition, the crystal-preferred orientations (CPO) of olivine, ortho- and clinopyroxene, and garnet, the Fe content of olivine, and the pressures and temperatures at which the rocks were equilibrated. These data allow constraining the variation of seismic anisotropy and velocities within the cratonic mantle. The fastest P and S2 wave propagation directions and the polarization of fast split shear waves (S1) are always subparallel to olivine [100] axes of maximum concentration, which marks the lineation (fossil flow direction). Seismic anisotropy is higher for high olivine contents and stronger CPO. Maximum P wave azimuthal anisotropy (AVp) ranges between 2.5 and 10.2% and the maximum S wave polarization anisotropy (AVs), between 2.7 and 8%. Changes in olivine CPO symmetry result in minor variations in the seismic anisotropy patterns, mainly in the apparent isotropy directions for shear wave splitting. Seismic properties averaged over 20 km-thick depth sections are, therefore, very homogeneous. Based on these data, we predict the anisotropy that would be measured by SKS, Rayleigh (SV) and Love (SH) waves for five endmember orientations of the foliation and lineation. Comparison to seismic anisotropy data from the Kaapvaal shows that the coherent fast directions, but low delay times imaged by SKS studies, and the low azimuthal anisotropy with with the horizontally polarized S waves (SH) faster than the vertically polarized S wave (SV) measured using surface waves are best explained by homogeneously dipping (45°) foliations and lineations in the cratonic mantle lithosphere. Laterally or vertically varying foliation and lineation orientations with a dominantly NW–SE trend might also explain the low measured anisotropies, but this model should also result in backazimuthal variability of the SKS splitting data, not reported in the seismological data. The strong compositional heterogeneity of the Kaapvaal peridotite xenoliths results in up to 3% variation in density and in up to 2.3% variation of Vp, Vs, and Vp / Vs ratio. Fe depletion by melt extraction increases Vp and Vs, but decreases the Vp / Vs ratio and density. Orthopyroxene enrichment due to metasomatism decreases the density and Vp, strongly reducing the Vp / Vs ratio. Garnet enrichment, which was also attributed to metasomatism, increases the density, and in a lesser extent Vp and the Vp / Vs ratio. Comparison of density and seismic velocity profiles calculated using the xenoliths' compositions and equilibration conditions to seismological data in the Kaapvaal highlights that (i) the thickness of the craton is underestimated in some seismic studies and reaches at least 180 km, (ii) the deep sheared peridotites represent very local modifications caused and oversampled by kimberlites, and (iii) seismological models probably underestimate the compositional heterogeneity in the Kaapvaal mantle root, which occurs at a scale much smaller than the one that may be sampled seismologically.

BackgroundAn allometric relationship between different electrocardiogram (ECG) parameters and infarcted ventricular mass was assessed in a myocardial infarction (MI) model in New Zealand rabbits.MethodsA total of fifteen animals were used, out of which ten underwent left anterior descending coronary artery ligation to induce infarction (7–35% area). Myocardial infarction (MI) evolved and stabilized during a three month-period, after which, rabbits were sacrificed and the injured area was histologically confirmed. Right before sacrifice, ECGs were obtained to correlate several of its parameters to the infarcted mass. The latter was normalized after combining data from planimetry measurements and heart weight. The following ECG parameters were studied: RR and PR intervals, P-wave duration (PD), QRS duration (QRSD) and amplitude (QRSA), Q-wave (QA), R-wave (RA) and S-wave (SA) amplitudes, T-wave peak amplitude (TA), the interval from the peak to the end of the T-wave (TPE), ST-segment deviation (STA), QT interval (QT), corrected QT and JT intervals. Corrected QT was analyzed with different correction formulae, i.e., Bazett (QTB), Framingham (QTFRA), Fridericia (QTFRI), Hodge (QTHO) and Matsunaga (QTMA) and compared thereafter. The former variables and infarcted ventricular mass were then fitted to the allometric equation in terms of deviation from normality, in turn derived after ECGs in 5 healthy rabbits.ResultsSix variables (JT, QTB, QA, SA, TA and STA) presented statistical differences among leads. QT showed the best allometric fit (r = 0.78), followed by TA (r = 0.77), STA (r = 0.75), QTFRA (r = 0.72), TPE (r = 0.69), QTFRI (r = 0.68) and QTMA (r = 0.68). Corrected QT’s (QTFRA, QTFRI and QTMA) performed worse than the uncorrected counterpart (QT), the former scaling allometrically with similar goodness of fits.ConclusionsQT, TA, STA and TPE could possibly be used to assess infarction extent in an old MI event through the allometric model as a first approach. Moreover, the TPE also produced a good allometric scaling, leading to the potential existence of promising allometric indexes to diagnose malignant arrhythmias.

To explore the efficacy and safety of radiofrequency catheter ablation (RCA) for ventricular premature beats originating from left coronary sinus under the guidance of 3-dimensional mapping system (CARTO). A total of 15 patients with premature ventricular contractions (PVCs) originating from left coronary sinus underwent CARTO-guided RCA. Anatomical structures were constructed and three-dimension (3D) electrical activation sequence was plotted for left ventricle and aortic sinus. The distance of earliest activation point of PVCs and origin of left coronary artery were surveyed after left coronary arteriography. The electrocardiogram (ECG) results showed that R-wave was upward in leads II, III and avF, QRS waves in lead I was mainly of rS, rs and rsr types, QS type in lead avL, RS, Rs and rS type in lead V(1), RS type in lead V(3) and absence of S wave in lead V(5)/V(6). Intraoperative mapping detected the earliest activation point on the posterior-inferior origin of left coronary artery (LMCA) ostium (n = 7), on the anterio-inferior of LMCA ostium (n = 3) and on the inferior of LMCA ostium (n = 5). The earliest activation point (local activation time) was shorter 86 - 120 ms than surface electrocardiogram QRS wave, discharge melting on the earliest activation point and nearby succeeded. PVCs disappeared, PVCs failed to be induced under similar preoperative conditions (aleudrin intravenous) and no complication occurred intraoperatively and postoperatively. The CARTO-guided RCA is a safe and effective in the treatment of PVCs originating from left coronary sinus.

This paper analyzes S-wave splitting analysis in terms of P-wave receiver functions and the SKS shear waves from the INDEPTH-III profile which consists of 41 seismic stations deployed in central Tibet. Using the weight average technique with a weighting factor of the measuring error, the direction and extent of seismic polarization anisotropy in the crust and upper mantle beneath central Tibet, from the central Lhasa terrane, across the Karakoram-Jiali fault and Bangong-Nujiang suture to the central Qiangtang terrane, were imaged. Substantial splitting of Pms phase with delay time 0.3 similar to 0.5 s, and fast directions varying from NE-SW in the Lhasa terrane to EW in the Qiangtang terrane, was observed. The delay time of SKS for stations in the northernmost Lhasa terrane and Qiangtang terrane is 1 similar to 2 s which increases near the Bangong-Nujiang suture and Jiali fault, and the fast direction of SKS is similar to the Pms. No detectable SKS splitting was observed for stations located farther south in the central Lhasa terrane, which is related to a model with two-layer anisotropy of perpendicular fast direction. In combination with previous geological and geophysical studies, we infer that the Lhasa crust possesses high rigidity and has not experienced rheological deformation, so that the fast direction of the anisotropy layer in the crust is consistent with the direction of the India-Eurasia convergence. However, the Qiangtang terrane is possibly weaker and more likely has been rheologically deformed during the convergence process, so that the fast direction of the anisotropy layer in the crust and upper mantle is coincident with escaping direction of material of the Tibetan plateau.