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Ultrasound is acoustic waves that can penetrate deeply into tissue in a focused manner with limited adverse effects on cells. As such, ultrasound has been widely used for clinical diagnosis for several decades. Ultrasound induces bioeffects in tissues, providing potential value in therapeutic applications. However, the intrinsic millimeter scale of the ultrasound focal zone represents a challenge with respect to minimizing the illuminated regions to perturb target cells in a precise manner. To control a specific cell population or even single cells, sonogenetic tools that combine ultrasound and genetic methods have been recently developed. With these approaches, several ultrasound-responsive proteins are heterologously introduced into target cells, which enhances the cells' ability to respond to ultrasound stimulation. With optimization of the ultrasound parameters, these tools can specifically manipulate activities in genetically defined cells but not in unmodified cells present in the ultrasound-illuminated regions. These approaches provide new strategies for noninvasive modulation of target cells in various therapeutic applications.

Whisker sensory system plays crucial role in development of brain functions in rats. In WAG/Rij rats with genetic predisposition to absence epilepsy, the area of whiskers’ projection in the somatosensory cortex (barrelfield) is known to contain hyperexcitable neurons which form epileptic focus. Neonatal period of development (PN1–8) is critical for development of whisker sensory system. Whisker deafferentaion during this period causes irreversible plastic changes that considerably impact brain functions in adulthood. Bilateral trimming of all whiskers in WAG/Rij rats during PN1–8 affected seizure activity between 5 and 9 months of age. First, it prevented age-related increase in the number of seizures, suggesting consistency of epileptic activity in the cortical focal zone; second, it prevented age-related increase in seizure duration, suggesting consistency of thalamo-cortical synchronization. Unilateral whisker trimming on PN1–8 increased excitability of pyramidal cells in the intact barrelfild mediated by HCN-related processes.

Ultrasound appears to be the most useful imaging tool in the diagnosis and guided treatment of musculoskeletal disorders. However, ultrasonography has been criticized for being user dependent. Therefore, medical professionals should be familiar with the basic principles of ultrasound imaging (e.g., physics and technical skills) to diminish artifacts and avoid misinterpretation. In this review, we focused on the physics of common artifacts, their clinical significance, and the ways to tackle them in daily practice during musculoskeletal imaging. In particular, artifacts pertaining to the focal zone, beam attenuation, path and side lobe of the beam, speed of the sound, and range ambiguity were described.

International audience; The proliferation of photovoltaic (PV) power generation in power distribution grids induces increasing safety and service quality concerns for grid operators. The inherent variability, essentially due to meteorological conditions, of PV power generation affects the power grid reliability. In order to develop efficient monitoring and control schemes for distribution grids, reliable forecasting of the solar resource at several time horizons that are related to regulation, scheduling, dispatching, and unit commitment, is necessary. PV power generation forecasting can result from forecasting global horizontal irradiance (GHI), which is the total amount of shortwave radiation received from above by a surface horizontal to the ground. A comparative study of machine learning methods is given in this paper, with a focus on the most widely used: Gaussian process regression (GPR), support vector regression (SVR), and artificial neural networks (ANN). Two years of GHI data with a time step of 10 min are used to train the models and forecast GHI at varying time horizons, ranging from 10 min to 4 h. Persistence on the clear-sky index, also known as scaled persistence model, is included in this paper as a reference model. Three criteria are used for in-depth performance estimation: normalized root mean square error (nRMSE), dynamic mean absolute error (DMAE) and coverage width-based criterion (CWC). Results confirm that machine learning-based methods outperform the scaled persistence model. The best-performing machine learning-based methods included in this comparative study are the long short-term memory (LSTM) neural network and the GPR model using a rational quadratic kernel with automatic relevance determination.

In this paper, the design process steps of a conventional solar parabolic trough with large rim angle are presented. The various parameters which intervene to obtain the suitable parabolic trough form of the concentrator are applied. Through an experimental characterization, the real focal distance and the focal zone size of the designed concentrator have been determined and compared with those calculated theoretically. Then, its concentration ratio is evaluated and the focused solar flux at the focal zone along the absorber tube is calculated using Soltrace code. It should be noted that the wind speed effect was not taken into account in the experimental tests which are conducted under a solar irradiation of 970 W/m2 and a receiver inclination angle of 36° which corresponds to the experimentation site latitude.

Based on the data on earthquake focal mechanisms, we estimated seismotectonic deformation related to the 2010 Мw 8.8 Maule earthquake and analyzed the deformation at different depths. In the main seismic dislocation of the Maule earthquake and the northern area, the deformation field to a depth of 70 km is typical of subduction zones as evidenced by shortening in the direction of the oceanic plate subduction. Below a depth of 70 km, the deformation pattern changes sharply to horizontal stretching. After the main seismic event, as well as before it, nearlatitudinal shortening was dominant in the focal zone, while the region of the main seismic dislocations was surrounded by separate areas of near-latitudinal stretching, which is an opposite type of deformation. We conducted a detailed analysis of the seismotectonic deformations in the oceanic uplift area to the west of the deep-water trough and identified local zones of near-latitudinal stretching near the southern and northern boundaries of the future Maule earthquake zone. Detecting such zones can provide important data for early forecasting of regions wherein strong subduction-related earthquakes are being prepared.

High intensity focused ultrasound (HIFU) has gained clinical interest as a non-invasive local tumour therapy in many organs. In addition, it has been shown that lung cancer can be targeted by HIFU using One-Lung Flooding (OLF). OLF generates a gas free saline-lung compound in one lung wing and therefore acoustic access to central lung tumours. It can be assumed that lung parenchyma is exposed to ultrasound intensities in the pre-focal path and in cases of misguiding. If so, cavitation might be induced in the saline fraction of flooded lung and cause tissue damage. Therefore this study was aimed to determine the thresholds of HIFU induced cavitation and tissue erosion in flooded lung. Resected human lung lobes were flooded ex-vivo. HIFU (1,1 MHz) was targeted under sonographic guidance into flooded lung parenchyma. Cavitation events were counted using subharmonic passive cavitation detection (PCD). B-Mode imaging was used to detect cavitation and erosion sonographically. Tissue samples out of the focal zone were analysed histologically. In flooded lung, a PCD and a sonographic cavitation detection threshold of 625 Wcm − 2(p r = 4, 3 MPa) and 3.600 Wcm − 2(p r = 8, 3 MPa) was found. Cavitation in flooded lung appears as blurred hyperechoic focal region, which enhances echogenity with insonation time. Lung parenchyma erosion was detected at intensities above 7.200 Wcm − 2(p r = 10, 9 MPa). Cavitation occurs in flooded lung parenchyma, which can be detected passively and by B-Mode imaging. Focal intensities required for lung tumour ablation are below levels where erosive events occur. Therefore focal cavitation events can be monitored and potential risk from tissue erosion in flooded lung avoided.

The purpose of this study is to evaluate the image quality for linear transducers on the basis of a quality control (QC) protocol using the ATS-550 phantom (ATS, Laboratories, Bridgeport, CT, USA). To evaluate the image QC, we used two linear transducers L9 and ML6-15 and performed eight examinations, which included qualitative and quantitative analyses by three observers. The qualitative analyses mostly showed no difference between the two transducers at various frequencies. However, in the functional resolution, the distinguishing ability of anechoic holes ranged between 13 and 15 MHz in the ML6-15 transducer. For quantitative analyses, the vertical and the horizontal measurements were in the range of 2.00 - 2.02 cm, and the focus rate (%) in the focal zone was greater than 75% (range: L9, 85.22 - 89.78%; ML6 - 15, 81.72 - 88.21%) in most the transducers. For sensitivity, the L9 transducer values (mean ± SD) for all frequencies were 6.02 ± 0.01 cm and the ML6-15 transducer values (mean ± SD) for frequencies 9, 11, 13, and 15 MHz were 6.03 ± 0.02, 6.01 ± 0.01, 5.03 ± 0.05, and 4.03 ± 0.05 cm, respectively. For the signal-to-noise ratio of the gray scale and dynamic image, the mean values of the L9 transducer for frequencies 5, 5.5, 6, 7, and 9 MHz were 2.50 ± 1.44, 2.64 ± 1.52, 2.47 ± 1.43, 2.13 ± 1.35, and 2.03 ± 1.24, respectively. The mean values of the ML6-15 transducer for frequencies 9, 11, 13, and 15 MHz were 4.02 ± 1.67, 3.56 ± 1.60, 2.18 ± 1.14, and 2.48 ± 1.01, respectively. For the contrast-to-noise ratio of the gray scale and dynamic image, mean values of the L9 transducer and the ML6-15 transducer were in the ranges of 0.82 - 0.98 and 0.97 - 1.05, respectively. The image quality of the linear transducer depends on the frequency whereas the diagnostic values depend on the transducer and the frequency selected. As yet, the QC of linear transducers has no standard protocol. The results of this study can be used to understand the characteristics of linear transducers and perform QC tests. Consequently, periodic QC testing of linear transducers can provide improved image quality and increased diagnostic values.

Mathematical modeling of wave processes in a tense medium in the event of a sudden rupture with contacting banks was carried out using an analytical solution by Kim A.S. for a dynamic problem simulating the process of an earthquake. The displacement field in the zone of final rupture with viscous contact of the banks is obtained. The results of numerical analysis confirm the theoretical conclusions about the presence of a time interval during which the influence of the ends of the rupture on the movement of its banks can be neglected, and this time interval increases with increasing viscosity at the rupture. A computer visualization of the development in time of the total field of displacements in the focal zone was carried out, taking into account the field of repeated cylindrical waves, when a complete release of stresses occurs at the final rupture. It has been established that on the trunk rupture, reverse displacements of the banks of the rupture can occur, and the total displacement field in the rupture zone tends to its static state.

A gas geochemical precursor anomaly was identified prior to the October 2008 Nový Kostel (Czech Republic) earthquake swarm with a peak magnitude ML of 3.8. This anomaly was observed as a deviation of CO2 concentrations from the long-term annual CO2 concentration trend in the gas extracted from the scree at the Nový Kostel and Oldřisska gas monitoring stations, which are directly above the Plesna valley-Pocatky and Marianske Lazně fault systems. Both sites are located within the major focal zone of the NW Bohemian swarm earthquake region at the northern edge of the Cheb Basin. A decrease in CO2 concentration started at Nový Kostel in September 2008, 17 days before the swarm, opposite to the usually increasing annual trend in the autumn period, and ended with a nearly coseismic drop immediately prior to the onset of the first swarm. The CO2 concentrations at Oldřisska, deviating from the annual trend, did not further increase after August 2008. The calculated horizontal strain field, based on the data of two permanent Global Navigation Satellite Systems stations, proved there was horizontal compression in this period. The increasing compression along the Plesna valley-Pocatky and Marianske Lazně fault systems during the stress build-up reduced the fault permeability prior to this earthquake swarm as indicated by the decrease in CO2 concentration. The 17-day duration of the earthquake precursor at Nový Kostel and about 65 days at Oldřisska lie within the range of the precursor times that are hypothesized worldwide for an ML = 3.8 earthquake. The nature of earthquake precursors and their origin are discussed, for example, as an indication of changed fault permeability by stress build-up in the case of the Nový Kostel swarm earthquake precursor or as fault opening in other cases.

BACKGROUND:\ud \ud A better understanding the mechanisms of cerebral ischemia is important both for diagnosis and treatment.\ud \ud OBJECTIVE:\ud \ud The study aimed to quantify several characteristics of magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) to indicate the brain tissue changes at different stage of cerebral ischemia in rats.\ud \ud METHODS:\ud \ud In the present study, a rat model of cerebral ischemia was established by middle cerebral artery occlusion (MCAO) in the left hemisphere. MRI and MRS were performed on 15 Sprague Dawley rats 4 H, 24 H, and 1 W after MCAO. Apparent diffusion coefficient (ADC), relative ADC including FNR, PNR, PNF, and metabolite ratio NCC were proposed to reflect the changes of water diffusion and metabolism in brain tissue.\ud \ud RESULTS:\ud \ud ADCs of focal zone and penumbra zone from 1 W group were significantly larger than those from 4H group, respectively (both p

According to our data, the involvement of the fundamental laws of physics, in particular, consideration of an earthquake as a particular macroprocess with a peak together with the thermofluctuational activation of mechanical stresses in some environments, makes it possible to move beyond the traditional idea of the issue of earthquake prediction. Many formal parameters of statistical processing of the geophysical data can be provided with a physical sense related to the mesomechanics of structural changes in a stressed solid body. Measures for improving the efficiency of observations and their mathematical processing to solve the forecasting issues have been specified.

We evaluated the influence of settings on an ultrasound machine on the configuration of a single B-line in a healthy model and analyzed the frequency spectrum. We also devised simple experimental models that generated B-line-like artifacts and evaluated the influence of the machine settings on the configuration. Visualization of B-lines was affected by the spatial compound imaging, the focal zone and the frequency. The spectra of both the B-line and non-B-line region at the same depth had the same center frequency and bandwidth. B-line-like artifact was generated by a spindle-shaped juice sac of a mandarin orange, an edible string-shaped glucomannan gel, glass beads and glass plates. Visualization of B-line-like artifacts was also affected by these machine settings. Our study indicated that the physical basis of some B-lines is multiple reverberations. B-line-like artifacts provide clues for solving key issues, such as the physical basis of B-lines, the sonographic-pathologic correlation in B-lines and the effects of machine settings.

Histotripsy is a tissue ablation method that utilizes focused, high-amplitude ultrasound to generate a cavitation bubble cloud that mechanically fractionates tissue. Effective histotripsy depends on the initiation, control, and maintenance of cavitation bubble clouds in the targeted area. In this study, we hypothesized that a low-pressure acoustic pulse sequence applied before and/or during histotripsy therapy would increase the cavitation initiation pressure threshold and the growth of cavitation bubble clouds. This technique could shrink or “sharpen” the focal zone during histotripsy to produce more precise and well-defined lesions with minimal collateral damage. It may also be a way to actively protect the soft tissue from cavitation damage during lithotripsy by increasing the pressure threshold for bubble cloud initiation. We applied these low-amplitude acoustic pulse sequences before and during histotripsy treatments with the pulse repetition frequency of 1 and 100 Hz, in three different mediums: water, tissue phantom agarose gel, and bovine liver in vitro . Acoustic backscatter signals and optical imaging were used to detect and monitor the initiation, maintenance, and growth of the resulting cavitation bubble cloud. The results demonstrated that the use of low-amplitude acoustic pulse sequences could increase the cavitation pressure amplitude threshold by 20% in the targeted area.

Transcranial Doppler ultrasound (TCD) is a non-invasive ultrasound method used to examine blood circulation within the brain. During TCD, ultrasound waves are transmitted through the tissues including skull. These sound waves reflect off blood cells moving within the blood vessels, allowing the radiologist to interpret their speed and direction. In this paper, an auto TCD probe is developed to control the 2D deflection angles of the probe. The techniques of Magnetic Resonance Angiography (MRA) and Magnetic Resource Imagine (MRI) have been used to build the 3D human head model and generate the structure of cerebral arteries. The K-Nearest Neighbors (KNN) algorithm as a non-parametric method has been used for signal classification and regression of corresponding arteries. Finally, a global search and local search algorithms are used to locate the ultrasound focal zone and obtain a stronger signal efficient and more accurate result.

Two new species of the genus Cobitis from southern China, C. hereromacula from the Luohe River in Guangdong Province and C. baishagensis from the Nandujiang River in Hainan Province, are described and illustrated here. C. hereromacula can be distinguished from its congeners by possessing the following combination of characteristics: absence of the second and third pigmentary zones of Gambetta; 13–16 oval blotches on the dorsum and 10–13 vertical, elongated triangular blotches below the midlateral line with more than 20 vertical dark brown bars between them; 6–7 narrow rows of dark spots on the caudal fin; a vertical oval spot smaller than the eye diameter on the upper part of the caudal peduncle; pointed mental lobes of the lower lip pointed with a slightly filiform tip; one slender and long needle-shaped lamina circularis at the base of the first branched ray of the male pectoral fins. C. baishagensis can be distinguished from its congeners by the fourth Gambetta zone being covered by 10–12 transverse elongated blotches; 4–5 narrow rows of dark spots on the caudal fin; a vertical blotch smaller than the eye diameter on the upper part of the caudal peduncle; males with a slender and long needle-shaped lamina circularis at the second branched pectoral fin ray in males; large scales with a slightly large focal zone; undeveloped mental lobes with a lower lip that does not end posteriorly in a filiform tip.

The results of the study of the field of shear-wave attenuation in the focal zone of the 2003 Altai earthquake using a short-period coda method are presented. The attenuation field of the Altai earthquake focal zone includes blocks with a high Q-factor and linear weakened zones. During the main shock, surface rupture is confined to the zone of strong attenuation. The epicenters of the main shock and its two strongest aftershocks are located in the zones of maximally contrasting shear-wave attenuation in the Earth’s crust and the upper mantle. The subcrustal fluid-saturated layer here is characterized by high viscosity, which is apparently the reason for the relatively low level of seismic activity in the Altai.

The spatiotemporal evolution of the intense burst in seismogenesis within the Andaman-Sumatra island arc in 2000–2010 is analyzed. The onset of seismogenic activation was marked by two strong (MS ∼ 7.9, MS ∼ 7.8) quakes that occurred in the lithosphere of the South Sumatra region on June 4, 2000 and by the strongest (MW = 7.3) earthquake of July 25, 2004 that took place in the lower part of the focal zone. These seismic events were the foreshocks of the main episode of seismogenic activation of the island arc—the catastrophic earthquake of December 26, 2004, with its source near the northern coast of Sumatra. The large shocks (MS ∼ 7.7–8.4) that occurred from March 28, 2005 to October 25, 2010 between the source of the Sumatran earthquake and epicentral zone of the foreshocks of June 4, 2000, are the aftershocks of the Sumatran event. The spatiotemporal evolution of seismogenic activation of the Andaman-Sumatra island arc at the beginning of the 21st century is compared to the seismogenic activation of the Kuril-Kamchatka arc in the middle of the 20th century. The positions, geological conditions, and focal parameters of the strongest Sumatran earthquakes of 2000–2010 are determined. The interpretation of the sources relies on the (1) complex analysis of all the manifestations of the earthquakes of 2000–2010 and (2) the established regularities of the occurrence of the earthquakes in the island arcs. The sources of the earthquakes of 2005–2010 are the steep longitudinal (trending along the arc) reverse faults of a backthrust type, which have a bedding depth of about a few dozen kilometers. The reverse-fault sources of the earthquakes of March 28, 2005, September 12, 2007 (11:10 UT), and October 10, 2010 are located in the zone of the Outer Range, and the earthquakes of September 12, 2007 (23:49 UT) fall in the Mentawai Trough. The strike-slip reverse fault, which cuts the island arc, is likely to be the focal mechanism of the earthquake of June 4, 2000. The sources of the events of March 28, 2005 and September 12, 2007 did not coincide with the sources of the historical devastating earthquakes of 1861 and 1833, respectively. The system of seismic sources in the form of a series of subparallel arc-parallel steep reverse faults off the western coast of Sumatra is similar to the system of seismic sources in the Kuril-Kamchatka island arc.

// Xiang Zhang 1, 2 , Jiangang Hu 1, 2 , Guanjian Zhao 1, 2 , Ning Huang 1 , Ying Tan 1 , Li Pi 1 , Qing Huang 1 , Feng Wang 1 , Zhigang Wang 2 , Zhibiao Wang 3 , Yuan Cheng 1 1 Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, 400010, China 2 Chongqing Key Laboratory of Ultrasound Molecular Imaging, Institute of Ultrasound Imaging of Chongqing Medical University, Chongqing, 400016, China 3 Chongqing Key Laboratory of Biomedical Engineering, College of Biomedical Engineering of Chongqing Medical University, Chongqing, 400016, China Correspondence to: Yuan Cheng, email: chengyuan023@aliyun.com Keywords: blood brain barrier, focused ultrasound, acoustic droplet vaporization, perfluoropentane, PLGA Received: January 17, 2017 Accepted: April 05, 2017 Published: April 17, 2017 ABSTRACT Previous studies have shown that focused ultrasound (FUS) combined with systematic administration of microbubbles (MBs) can open the blood brain barrier (BBB) locally, transiently and reversibly. However, because of the micro size diameters, MBs are restricted in the intravascular space and cannot extravasate into diseased sites through the opened BBB. In this study, we fabricated one kind of nanoscale droplets which consisted of encapsulated liquid perfluoropentane cores and poly (ethyleneglycol) - poly (lactide-co-glycolic acid) shells. The nanodroplets had the capacity to realize liquid to gas phase shift under FUS. Significant extravasation of Evan’s blue appeared when acoustic pressure reached 1.0 MPa. Intracerebral hemorrhages and erythrocyte extravasations were observed when the pressure was increased to 1.5 MPa. Prolonged sonication duration could enhance the level of BBB opening and broaden the time window simultaneously. Furthermore, compared with MBs, the distribution of EB extravasation was firmly confined within narrow region in the center of focal zone, suggesting the site of FUS induced BBB opening could be controlled with high precision by this procedure. Our results show the feasibility of serving PEGylated PLGA-based phase shift nanodroplet as an effective alternative mediating agent for FUS induced BBB opening.

The Vogtland and NW Bohemia region is known for its earthquake swarms; the most intensive swarm since 1985/86 occurred in October 2008. To find further indications for the interaction of ascending mantle-derived fluids and the occurrence of earthquake swarms, detailed fortnightly studies of gas compositions (CO2, N2, Ar, He, H2, and CH4) and isotope ratios (δ13C, δ15N, and 3He/4He) were carried out between October 2008 and April 2011 at four locations close to the Nový Kostel focal zone and at the Wettinquelle spring (Bad Brambach). From the start of the 2008 earthquake swarm seismically induced isotope-geochemical anomalies were recorded at locations along the Pocatky-Plesna fault zone (PPZ) and were, for the first time, also found at degassing locations on the Marianske Laznĕ fault zone (MLF). Variations were observed in both the temporal and spatial distributions of the anomalies as well in anomaly strengths, probably due to the positions of these fault zones relative to the focal zone, and to differences in fluid migration pathways. Prior to both the 2000 and 2008 swarms, 3He/4He ratios > 6 Ra were recorded at the Bublak mofette. These anomalous pre-seismic 3He/4He ratios suggest that both the 2000 and 2008 swarms may have been associated with the supply of fresh magma from a less degassed reservoir in the lithospheric mantle. The temporal δ13CCO2 pattern from detailed studies at Bublak between 2005 and 2011 indicates progressive magma degassing, as well as seismically induced variations in the δ13C, providing additional support to the interpretation derived from the 3He/4He ratios.

Focal zone, basic shock, jerking of strongest aftershocks and progress of seismic energy release during the aftershock process of the earthquake Maule 27.02.2010 (M W =8,8) in Chile have been analyzed. Macroseismic manifestations, tectonic position of the focus and reconstruction of acting plane position in the focus have been considered. Geophysical treatment of anomalous gravimagnetic disturbances and seismic precursors induced in variations of magnetic field and geoacoustic fields of the Earth during preparation of the basic shock and of three strongest iterative shocks on March 11 —16 2010 has been done for the first time. It has been shown that application of present-day cosmic observations, which allow to analyze gravity disturbances (so far only coseismic), reflected on the Earth’s surface makes possible to consider the precursors of seismic shocks of the arthquake Maule and other seismic events in a new way. Long-, middle- and short-term approaches to prognostication of strong seismic events both on land and sea have been stated

The fuel and energy complex is the basis for the development of all sectors of the Russian economy. Its most important element is trunk pipeline system for the transport of gas, oil and their products. The main gas pipelines with cathodic protection, are exposed to the impact of ground electrolytes and tensile stresses. As a result, corrosion cracks may appear on the pipe surface. One of the most dangerous types of destruction of gas pipelines is stress-crack corrosion (SCC) of the outside cathode-protected metal surface of the pipes. There are no efficient methods for SCC control at present (the only method for SCC control is application of anti-corrosive insulation). One of the methods for detection of stress-crack corrosion is the stress test, however, its application is justified only for single cracks. There is a system of cracks in practice. Analysis of the focal zone of the collapsed gas pipeline with multiple cracks was carried out in this research. Studies were conducted on a sample of X70 steel made in Japan, selected from the focal zone of destruction of the West Siberia gas pipeline. The sample has 4 cracks typical for SCC crack. A metallographic analysis of the X70 steel and the calculation of the stress-strain condition of the metal were carried out. On the basis of the obtained results, it is proved that tested cracks have a corrosion-mechanical origin typical for stress-crack corrosion.

The question of the formation of pulses with different duration and capacity in the focal zone of paraboloid mirror concentrating systems (PMC) is considered. The analysis of different types of regulators (shutters) is performed. Curtain and rotary shutters are developed and proposed, which provide the obtaining of light pulses with different shapes and power with a duration of one second and more.

Conduct a laboratory evaluation of a novel low-pressure, broad focal zone electrohydraulic lithotripter (TRT LG-380).Mapping of the acoustic field of the LG-380, along with a Dornier HM3, a Storz Modulith SLX, and a XiXin CS2012 (XX-ES) lithotripter was performed using a fiberoptic hydrophone. A pig model was used to assess renal response to 3000 shockwaves (SW) administered by a multistep power ramping protocol at 60 SW/min, and when animals were treated at the maximum power setting at 120 SW/min. Injury to the kidney was assessed by quantitation of lesion size and routine measures of renal function.SW amplitudes for the LG-380 ranged from (P(+)/P(-)) 7/-1.8 MPa at PL-1 to 21/-4 MPa at PL-11 while focal width measured ~20 mm, wider than the HM3 (8 mm), SLX (2.6 mm), or XX-ES (18 mm). For the LG-380, there was gradual narrowing of the focal width to ~10 mm after 5000 SWs, but this had negligible effect on breakage of model stones, because stones positioned at the periphery of the focal volume (10 mm off-axis) broke nearly as well as stones at the target point. Kidney injury measured less than 0.1% FRV (functional renal volume) for pigs treated using a gradual power ramping protocol at 60 SW/min and when SWs were delivered at maximum power at 120 SW/min.The LG-380 exhibits the acoustic characteristics of a low-pressure, wide focal zone lithotripter and has the broadest focal width of any lithotripter yet reported. Although there was a gradual narrowing of focal width as the electrode aged, the efficiency of stone breakage was not affected. Because injury to the kidney was minimal when treatment followed either the recommended slow SW-rate multistep ramping protocol or when all SWs were delivered at fast SW-rate using maximum power, this appears to be a relatively safe lithotripter.

The information on seismic loading and vibration effect is significant when assessing stability of underground spaces located in the vicinity of seismic active areas. Underground structures are well known to be earthquake resistant. Nevertheless, the existence of discontinuities makes them vulnerable to collapses, particularly in case of shallow underground openings. This study presents results of long-term seismic monitoring performed in the shallow medieval mine. This mine is located at a distance of about 25 km southeast of Nový Kostel focal zone (West Bohemia, Czech Republic), where seismic activity in the form of seismic swarms occurs. The most intensive earthquakes were documented here in the past with local magnitude M L =5.0. During two intensive seismic swarms from the Nový Kostel focal zone in 2008 (M L ≤3.8) and 2011 (M L ≤3.7), almost 2000 earthquakes were recorded at the seismic station in the mine. Vibration effect underground was analysed together with results of geomechanical monitoring. Based on the measured data, vibration effect in the mine was extrapolated for an expected more intensive earthquake with the local magnitude M L =5.0.

In this study, we establish the empirical relationships between the spatial dimensions of the aftershock zones and moment magnitudes ( M w) for the Taiwan region. The length ( l ) and width ( w ) of the aftershock zone of an earthquake is measured by the major and minor axes, respectively, of the ellipse of a two‐dimensional Gaussian distribution of one‐day aftershocks. Our data is composed of 649 mainshocks (depth≤70 km, M w 4.0–7.6) between 1990 and 2011. The relationships between aftershock zone dimensions and M w were obtained by least‐squares method with the corresponding uncertainties estimated by bootstrap. Our study confirms that aftershock zone dimensions are independent of faulting types and the seismic moment is proportional to l 3. The ratio ( w / l ) increases slightly with M w and is independent of faulting types. Together with previous study, our results suggest that earthquakes of both small ( M w=4.0) and large ( M w≥7.0) magnitudes have similar focal zone geometrical parameters. By using the M w– S relation, where the aftershock zone area S is estimated from l and w , we also provide an independent examination of the variations in the median stress drop. We find that the median stress drops of strike‐slip earthquakes are higher than those of thrust events. Moreover, the median stress drops are independent of the moment magnitudes for normal and strike‐slip events but decrease for large thrust events. These results are consistent with the latest global observations. Regardless of faulting types, the median stress drop decreases for larger (6≤ M w≤7.6) and relatively deep (depth∼60–70 km) earthquakes. Online Material: Effect of up‐dip rupture propagation on estimated maximum slip duration, details on teleseismic and geodetic stations, and figures of far‐field displacements, temporal change in slip, and snapshots of the semblance‐value distribution.