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The 1989 Mw 6.9 Loma Prieta earthquake is the first major event to occur along the San Andreas fault (SAF) zone in central California since the 1906 M 7.9 San Francisco earthquake. Given the complexity of this event, uncertainty has persisted as to whether this earthquake ruptured the SAF itself or a secondary fault. Recent work on the SAF in the Coachella Valley in southern California has revealed similar complexity, arising from a nonplanar, nonvertical fault geometry, and has led us to reexamine the Loma Prieta event. We have compiled data sets and data analyses in the vicinity of the Loma Prieta earthquake, including the 3D seismic velocity model and aftershock relocations of Lin and Thurber (2012), potential field data collected by the U.S. Geological Survey following the earthquake, and seismic refraction and reflection data from the 1991 profile of Catchings et al. (2004). The velocity model and aftershock relocations of Lin and Thurber (2012) reveal a geometry for the SAF that appears similar to that in the Coachella Valley (although rotated 180°): at Loma Prieta the fault dips steeply near the surface and curves with depth to join the moderately southwest-dipping main rupture below 6 km depth, itself also nonplanar. The SAF is a clear velocity boundary, with higher velocities on the northeast, attributable to Mesozoic accretionary and other rocks, and lower velocities on the southwest, attributable to Cenozoic sedimentary and volcanic rocks of the La Honda block. Rocks of the La Honda block have been offset right-laterally hundreds of kilometers from similar rocks in the southern San Joaquin Valley and vicinity, providing evidence that the curved northeast fault boundary of this block is the plate boundary. Thus, we interpret that the Loma Prieta earthquake occurred on the SAF and not on a secondary fault.

SUMMARY In the Gulf of California, Mexico, the relative motion across the North America–Pacific boundary is accommodated by a series of marine transform faults and spreading centres. About 40 M> 6 earthquakes have occurred in the region since 1960. On 2009 August 3, an Mw 6.9 earthquake occurred near Canal de Ballenas in the region. The earthquake was a strike-slip event with a shallow hypocentre that is likely close to the seafloor. In contrast to an adjacent M7 earthquake, this earthquake triggered a ground-motion-based earthquake early warning algorithm being tested in southern California (∼600 km away). This observation suggests that the abnormally large ground motions and dynamic strains observed for this earthquake relate to its rupture properties. To investigate this possibility, we image the rupture process and resolve the slip distribution of the event using a P-wave backprojection approach and a teleseismic, finite-fault inversion method. Results from these two independent analyses indicate a relatively simple, unilateral rupture propagation directed along-strike in the northward direction. However, the average rupture speed is estimated around 4 km s−1, suggesting a possible supershear rupture. The supershear speed is also supported by a Rayleigh wave Mach cone analysis, although uncertainties in local velocity structure preclude a definitive conclusion. The Canal de Ballenas earthquake dynamically triggered seismicity at multiple sites in California, with triggering response characteristics varying from location-to-location. For instance, some of the triggered earthquakes in California occurred up to 24 hr later, suggesting that nonlinear triggering mechanisms likely have modulated their occurrence.

SUMMARY We present our estimations and comparisons of the in situ Vp/Vs ratios and seismicity characteristics for the Parkfield segment of the San Andreas fault in northern California and the San Jacinto Fault Zone and its adjacent regions in southern California. Our results show that the high-resolution in situ Vp/Vs ratios are much more complex than the tomographic Vp/Vs models. They show similar variation patterns to those in the tomographic Vp models, indicating that Vp/Vs ratios are controlled by material properties but are also strongly influenced by fluid contents. In Parkfield, we observe velocity contrasts between the creeping and locked sections. In southern California, we see small-scale anomalous Vp/Vs variation patterns, especially where fault segments intersect, terminate and change orientations. In addition, our investigation confirms that the seismicity in Parkfield is more repeatable than in southern California. However, the earthquakes in the southernmost portion of the San Andreas fault, the trifurcation area of the San Jacinto Fault Zone and the Imperial fault are as much likely falling into clusters as those in Parkfield. The correlation of highly similar events with anomalous in situ Vp/Vs ratios supports the important role of fluids in the occurrence of repeating earthquakes. The high-resolution Vp/Vs ratio estimation method and the corresponding results are helpful for revealing roles of fluids in driving earthquake, fault interaction and stress distribution in fault zones.

Background T cells expressing a chimeric antigen receptor (CAR) engineered to target CD19 can treat leukemia effectively but also increase the risk of complications such as cytokine release syndrome (CRS) and CAR T cell related encephalopathy (CRES) driven by interleukin-6 (IL-6). Here, we investigated whether IL-6 knockdown in CART-19 cells can reduce IL-6 secretion from monocytes, which may reduce the risk of adverse events. Methods Supernatants from cocultures of regular CART-19 cells and B lymphoma cells were added to monocytes in vitro, and the IL-6 levels in monocyte supernatants were measured 24 h later. IL-6 expression was knocked down in regular CART-19 cells by adding a short hairpin RNA (shRNA) (termed ssCART-19) expression cassette specific for IL-6 to the conventional CAR vector. Transduction efficiency and cell proliferation were measured by flow cytometry, and cytotoxicity was measured by evaluating the release of lactate dehydrogenase into the medium. Gene expression was assessed by qRT-PCR and RNA sequencing. A xenograft leukemia mouse model was established by injecting NOD/SCID/γc-/- mice with luciferase-expressing B lymphoma cells, and then the animals were treated with regular CART-19 cells or ssCART-19. Tumor growth was assessed by bioluminescence imaging. Results Both recombinant IL-6 and CART-19 derived IL-6 significantly triggered IL-6 release by monocytes. IL-6 knockdown in ssCART-19 cells dramatically reduced IL-6 release from monocytes in vitro stduy. In vivo study further demonstrated that the mice bearing Raji cells treated with ssCART-19 cells showed significant lower IL-6 levels in serum than those treated with regular CART-19 cells, but comparable anti-tumor efficacy between the animal groups. Conclusion CAR T-derived IL-6 is one of the most important initiators to amplify release of IL-6 from monocytes that further drive sCRS development. IL-6 knockdown in ssCART-19 cells by shRNA technology provide a promising strategy to improve the safety of CAR T cell therapy.

A series of conjugate strike‐slip faults is the most prominent geologic feature in central Tibet and is considered to accommodate east‐west extension and coeval north‐south contraction. The development mechanism of the conjugate strike‐slip fault system is under debate because of unclear crustal physical properties and compositional variations. P and S wave arrivals from 414 local earthquakes recorded by the temporary Seismic Array Integrated Detection for a Window of Indian Continental Head array and the permanent China National Seismic Network were used for the velocity tomography, with additional P and S wave arrivals from 12 shots of the International Deep Profiling of Tibet and the Himalaya III reflection/refraction profile. The local earthquakes were simultaneously relocated with the updated velocity models. We also inverted for a three‐dimensional upper crustal Qp model with the same earthquake data set. The Vp structure near the surface shows that low‐Vp anomalies generally correspond to sedimentary basins and high‐Vp anomalies are related to exhumed metamorphic blocks in the study area. Relatively low Vp/Vs ratios in the upper crust indicate widely distributed quartz‐rich rocks. The low‐Vp zone from 0‐ to 10‐km depth (resolving depth limit) is spatially correlated with the Bangong‐Nujiang suture, possibly reflecting the compositional difference along the ophiolitic mélange belt accompanied by twin volcanic arcs from a double‐sided subduction. This interpretation is supported by relatively heterogeneous Qp values. This low‐velocity zone also implies relatively uniform stress and continuous deformation in the upper crust of central Tibet. The relatively weak materials in at least the upper crust would result in strain concentration and help the development of the conjugate strike‐slip fault system along the Bangong‐Nujiang suture.

The widely utilization of renewable energy with low output voltage makes the high voltage ratio boosting converter more popular. This article introduces a non-isolated low input ripple high step-up extendable hybrid DC-DC converter. The proposed converter is based on a two-phase interleaved BOOST converter and switch-capacitor (SC) boost circuit. One of the BOOST channels charges the capacitors in the SC circuit, and the other BOOST channel is connected in series with the capacitors to supply power to the load. Benefiting from this structure, the converter achieves high voltage gain, reduced semiconductor voltage stress, and low input current ripple. Moreover, the converter can be extended by increasing the number of switch-capacitor boost units or the parallel BOOST channels to perform better in voltage gain, input current ripple, and power density. The principle of operation, theoretical analysis, expansion scheme, and comparison with similar topologies are introduced in detail. Finally, a 100W prototype is implemented to verify the validity of the theoretical analysis.

Microplastic pollution has become a major global problem demanding prompt solution. So far, most research has focused on marine environment, but there is a lack of information about microplastic distribution, and persistence uptake in coastal soil environment. In this study, the Huangshui River Basin in Laizhou Bay and Dagu River Basin in Jiaozhou Bay of Shandong Province of China was taken as the research area. A total of 3,352 microplastic items were collected from 12 samples from the four sites in this study. The results showed that local soil was already affected by microplastics, of which 92.9% were particles, 6.1% were fibers, and only 1% were films. The existence of film PE indicated that the microplastic pollution in soil probably came from the plastic film. The degree of pollution was correlated with the size, and the size of microplastics was negatively correlated with abundance. Only a few labelled fibers were detected in groundwater samples, which may come from the external environment. This study contributes to a deeper understanding of environmental microplastic pollution in the coastal region.

We have developed an approach for the measurement of the effective focal length (EFL) and band-to-band registration (BBR) of selected spectral bands of satellite-borne whiskbroom imaging sensors from on-orbit data. Our approach is based on simulating the coarser spatial resolution whiskbroom sensor data with finer spatial resolution Landsat 7 Enhanced Thematic Mapper Plus or Landsat 8 Operational Land Imager data using the geolocation (Earth location) information from each sensor and computing the correlation between the simulated and original data. For each scan of a selected spectral band of the whiskbroom dataset, various subsets of the data are examined to find the subset with the highest spatial correlation between the original and simulated data using the nominal geolocation information. Then, for this best subset, the focal length value and the spatial shift are varied to find the values that produce the highest spatial correlation between the original and simulated data. This best focal length value is taken to be the measured instrument EFL, and the best spatial shift is taken to be the registration of the whiskbroom data relative to the Landsat data, from which the BBR is inferred. Best results are obtained with cloud-free subsets with contrasting land features. This measurement is repeated over other scans with cloud-free subsets. We demonstrate our approach with on-orbit data from the Aqua and Terra MODIS instruments and SNPP and J1 VIIRS instruments.

Additional file 3: Figure S3. Effect of IL-6 knockdown on ssCART-19 cell differentiation and gene expression. A Differentiation of ssCART-19 cells and regular CART-19 cells, as detected by flow cytometry, Tscm (stem central memory T cells), Tcm (central memory T cells), Tem (effector memory T cells), Teff (effector T cells). B Top differentially expressed genes in ssCART-19 and regular CART-19 cells after coculture with Raji cells, as analyzed by RNA sequencing. C Gene ontology enrichment analysis of the RNA sequencing data showing the top 30 enriched functions.

Additional file 1: Figure S1. CD19 expression in Raji and K562-CD19-LUC cells and CD14 expression in monocytes. A CD19 expression on Raji cells used for the mouse xenograft model and in vitro cytotoxicity assay. B CD14 expression in monocytes, as detected by flow cytometry.

The visible infrared imaging radiometer suite (VIIRS) instrument was launched on October 28, 2011 onboard the Suomi National Polar-Orbiting Partnership (SNPP) satellite. The VIIRS instrument is a whiskbroom system with 22 spectral and thermal bands split between 16 moderate resolution bands (M-bands), five imagery resolution bands (I-bands), and a day–night band. In this study, we estimate the along-scan line spread function (LSF) of the I-bands and M-bands based on measurements performed on images of the Lake Pontchartrain Causeway Bridge. In doing so, we develop a model for the LSF that closely matches the prelaunch laboratory measurements. We utilize VIIRS images co-geolocated with a Landsat TM image to precisely locate the bridge linear feature in the VIIRS images as a linear best fit to a straight line. We then utilize nonlinear optimization to compute the best fit equation of the VIIRS image measurements in the vicinity of the bridge to the developed model equation. From the found parameterization of the model equation, we derive the full-width at half-maximum as an approximation of the sensor field of view for all bands, and compare these on-orbit measured values with prelaunch laboratory results.

The visible infrared imaging radiometer suite (VIIRS) instrument onboard the Suomi National Polar-orbiting Partnership (SNPP) satellite was launched on October 28, 2011. The VIIRS instrument is a whiskbroom system with 22 spectral and thermal bands split between 16 moderate resolution bands (M-bands), 5 imagery resolution bands (I-bands), and a day–night band. In this study, we measure the along-scan and along-track band-to-band registration between the I-bands and M-bands from on-orbit data. This measurement is performed by computing the normalized mutual information (NMI) between shifted image band pairs and finding the amount of shift required (if any) to produce the peak in NMI value. Subpixel accuracy is obtained by utilizing a bicubic interpolation. The product of the NMI peak slope and the NMI peak value is shown to be a better criterion for evaluating the quality of the NMI result than just the NMI peak value. Registration shifts are found to be similar to prelaunch measurements and stable (within measurement error) over the instrument's first four years in an orbit.

Geothermal areas are long recognized to be susceptible to remote earthquake triggering, probably due to the high seismicity rates and presence of geothermal fluids. However, anthropogenic injection and extraction activity may alter the stress state and fluid flow within the geothermal fields. Here we examine the remote triggering phenomena in the Coso geothermal field and its surrounding areas to assess possible anthropogenic effects. We find that triggered earthquakes are absent within the geothermal field but occur in the surrounding areas. Similar observation is also found in the Salton Sea geothermal field. We hypothesize that continuous geothermal operation has eliminated any significant differential pore pressure between fractures inside the geothermal field through flushing geothermal precipitations and sediments out of clogged fractures. To test this hypothesis, we analyze the pore-pressure-driven earthquake swarms, and they are found to occur outside or on the periphery of the geothermal production field. Therefore, our results suggest that the geothermal operation has changed the subsurface fracture network, and differential pore pressure is the primary controlling factor of remote triggering in geothermal fields.

With the increasing need to construct long-term climate-quality data records to understand, monitor, and predict climate variability and change, it is vital to continue systematic satellite measurements along with the development of new technology for more quantitative and accurate observations. The Suomi National Polar-orbiting Partnership mission provides continuity in monitoring the Earth's surface and its atmosphere in a similar fashion as the heritage MODIS instruments onboard the National Aeronautics and Space Administration's Terra and Aqua satellites. In this paper, we aim at quantifying the consistency of Aqua MODIS and Suomi-NPP Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Reflectance (LSR) and NDVI products as related to their inherent spatial sampling characteristics. To avoid interferences from sources of measurement and/or processing errors other than spatial sampling, including calibration, atmospheric correction, and the effects of the bidirectional reflectance distribution function, the MODIS and VIIRS LSR products were simulated using the Landsat-8's Operational Land Imager (OLI) LSR products. The simulations were performed using the instruments' point spread functions on a daily basis for various OLI scenes over a 16-day orbit cycle. It was found that the daily mean differences due to discrepancies in spatial sampling remain below 0.0015 (1%) in absolute surface reflectance at subgranule scale (i.e., OLI scene size). We also found that the MODIS–VIIRS product intercomparisons appear to be minimally impacted when differences in the corresponding view zenith angles (VZAs) are within the range of $-\!\!15^{\circ}$ to $-35^{\circ}$ $(\textrm{VZA}_{V}-\textrm{VZA}_{M})$ , where VIIRS and MODIS footprints resemble in size. In general, depending on the spatial heterogeneity of the OLI scene contents, per-grid-cell differences can reach up to 20%. Further spatial analysis of the simulated NDVI and LSR products revealed that, depending on the user accuracy requirements for product intercomparisons, spatial aggregations may be used. It was found that if per-grid-cell differences on the order of 10% (in LSR or NDVI) are tolerated, the product intercomparisons are expected to be immune from differences in spatial sampling.

Two Moderate Resolution Imaging Spectroradiometer (MODIS) sensors have been in operations for more than 19 and 17 years (thus 36 combined years) as part of NASA's Earth Observing System (EOS) on the Terra platform that was launched in December 1999 and on the Aqua platform that was launched in May 2002, respectively. Accurate geolocation is a critical element needed for accurate retrieval of global biogeophysical parameters. In this paper, we describe the latest trends in the continuously improved MODIS geolocation accuracy in Collection-5 (C5), C6 and C6.1 re-processing and forward-processing data streams. We improved geolocation accuracy in the re-processed data and corrected for geolocation biases found in forward-processed data, including those caused by operations such as the stop-go-stop status of the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) instrument on the Aqua platform. We discuss scan-toscan underlaps near nadir over the equator regions that was discovered in checking the non-underlapping requirement in the Visible Infrared Imaging Radiometer Suite (VIIRS) based on trending parameters from the actual Suomi National Polar-orbiting Partnership (S-NPP) satellite orbit. The underlaps are closely tied to instrument effective focal length that is measured from on-orbit data using a technique we recently developed. We also discuss potential improvements for the upcoming C7 re-processing.

We present high-quality focal mechanisms based on a refined earthquake location catalog for the Island of Hawai'i, focusing on Mauna Loa and Kīlauea volcanoes. The relocation catalog is based on first-arrival times and waveform data of both compressional and shear waves for about 180,000 events on and near the Island of Hawai'i between 1986 and 2009 recorded by the seismic stations at the Hawaiian Volcano Observatory. We relocate all the earthquakes by applying ray tracing through an existing three-dimensional velocity model, similar event cluster analysis, and a differential-time relocation method. The resulting location catalog represents an expansion of previous relocation studies, covering a longer time period and consisting of more events with well-constrained absolute locations. The focal mechanisms are obtained based on the compressional-wave first-motion polarities and compressional-to-shear wave amplitude ratios by applying the HASH program to the waveform cross correlation relocated earthquakes. Overall, the good-quality (defined by the HASH parameters) focal solutions are dominated by normal faulting in our study area, especially in the active Ka'ōiki and Hīlea seismic zones. Kīlauea caldera is characterized by a mixture of approximately equal numbers of normal, strike-slip, and reverse faults, whereas its south flank has slightly fewer strike-slip events. Our relocation and focal mechanism results will be useful for mapping the seismic stress and strain fields and for understanding the seismic-volcanic-tectonic relationships within the magmatic systems.

We develop a new three-dimensional local earthquake tomography algorithm with the inclusion of full topography (LETFT). We present both synthetic and real data tests based on the P- and S-wave arrival time data for Kīlauea volcano in Hawai'i. A total of 33,768 events with 515,711 P-picks and 272,217 S-picks recorded by 35 stations at the Hawaiian Volcano Observatory are used in these tests. The comparison between the new and traditional methods based on the synthetic test shows that our new algorithm significantly improves the accuracy of the velocity model, especially at shallow depths. In the real data application, the P- and S-wave velocity models of Kīlauea show several intriguing features. We observe discontinuous high Vp (> 7.0 km/s) and Vs (> 3.9 km/s) zones at 5–14 km depth below Kīlauea caldera, its East Rift Zone (ERZ) and the Southwest Rift Zone, which may represent consolidated intrusive gabbro-ultramafic cumulates. At Kīlauea caldera, Vp and Vs decrease from ~ 3.9 km/s and ~ 2.6 km/s from the surface to ~ 3.7 km/s and ~ 2.3 km/s at 2 km depth. We resolve a high Vp zone (> 7.0 km/s) at 5–14 km depth and high Vs zone (> 3.9 km/s) at 5–11 km depth. This high Vp and Vs zone extends to the north of the ERZ at 5–10 km depth and to the upper ERZ at 8–12 km depth. In the Hilina Fault System, there is a high Vp layer (~ 7.0 km/s) at 4–6 km depth and a low Vp body of ~ 5.7 km/s at 6–11 km depth. The high Vp layer could be associated with the intrusive ultramafic gabbro sills. The velocity contrast on the north and south sides of the Koa'e Fault System indicates that the intrusive activities mainly occur to the north of the fault. Our new LETFT method performs well in both the synthetic and real data tests and we expect that it will reveal more robust velocity structures in areas with larger topographic variations.

Groundwater near the Qilu petrochemical plant in Zibo City is polluted by oil for over thirty years, which seriously threaten the local ecological environment. The results of GC-MS analysis of water samples show that benzene was the most abundant and toxic organic pollutant. The adsorption-desorption behaviour of benzene in soil was studied through batch experiments. The results indicated that the adsorption amount of benzene in the local soil showed a trend of increasing first and then decreasing with the increasing of the initial concentration of benzene. There existed an optimal initial concentration of benzene in the adsorption experiments. The desorption concentration of benzene was proportional to the initial concentration of benzene. Particle size of the soil was inversely related to adsorption and desorption concentration of benzene. The soil with the average particle size of 0.08 mm had the largest adsorption capacity for benzene, which could reach 376.39 mg/kg. The results could provide a theoretical basis for the local groundwater remediation.

Marine microplastic pollution is one of the hot spots in current marine environment research. The coastal zone has unique micro-plastic pollution characteristics at the junction of land and sea, and the micro-plastic pollution in the coastal zone soil is still unclear. In this study, Huangshui river basin was selected as the research area in Laizhou Bay, China. Soil samples were collected from the depth of 0-3, 3-6 and 6-9 cm at each location. Microplastics were separated by flotation. Microplastic characteristics were investigated and analyzed by Nile red staining and Fourier infrared spectrometer. The results showed that there was slight microplastic pollution in the coastal plain. 92.9% of the detected microplastics were granular, 6.1% were fibers, and only 1.0% were films. Microplastics with a particle size of 20-100 μm accounted for 57.9% of the total, particles with the size of 100-1000 μm accounted for 38.6%, and particles with the size of 1000-5000 μm accounted for 3.5%. The presence of film-like PE was detected, indicating that microplastic contamination in the soil was likely to come from the utilization and mulching of agricultural mulch. The amount of microplastics in soil was related to the size of microplastics. Abundance of microplastics in soil increased with decreasing of the size of soil. In addition, the microplastic content in soil decreased, and particles with a smaller size occupied a larger proportion, with the increasing of the depth of soil.

The Zhuxi ore deposit, located in Jiangxi province, South China, is the largest tungsten reserve in the world. To better understand the geological structure and distribution of orebodies, we conducted a high resolution three-dimensional P-wave velocity tomography of the uppermost 0.5 km beneath the Zhuxi ore deposit and adjacent area. Our velocity model was derived from 761,653 P-wave first arrivals from 998 control-source shots, recorded by a dense array. As the first 3D P-wave velocity structure of the Zhuxi ore deposit, our model agrees with local topographic and tectonic structures and shows depth-dependent velocity similar to laboratory measurements. The Carboniferous formations hosting the proven orebodies are imaged as high velocities. The high-velocity anomalies extend to a larger area beyond the proven orebodies, and the locations of high&ndash, low velocity boundaries are in accordance with the boundaries between the Neoproterozoic formation and the Carboniferous&ndash, Triassic formation. Seismic tomography reveals that high-velocity anomalies are closely related to the mineralized areas. Our results are helpful for further evaluating the total reserves and suggest that seismic tomography can be a useful tool for mineral exploration.

The first NOAA/NASA Join Polar Satellite System (JPSS-1) satellite was successfully launched on November 18, 2017,becoming NOAA-20. Instruments on-board the NOAA-20 satellite include the Visible Infrared Imaging RadiometerSuite (VIIRS). This instrument is the second build of VIIRS, with the first flight instrument on-board NASA/NOAASuomi National Polar-orbiting Partnership (SNPP) satellite operating since October 2011. The purpose of these VIIRSinstruments is to continue the long-term measurements of biogeophysical variables for multiple applications includingweather forecasting, rapid response and climate research. The geometric performance of VIIRS is essential to retrievingaccurate biogeophysical variables. This paper describes the early on-orbit geometric performance of the JPSS-1/NOAA-20 VIIRS. It first discusses the on-orbit orbit and attitude performance, a key input needed for accurate geolocation. Itthen discusses the on-orbit geometric characterization and calibration of VIIRS and an initial assessment of thegeometric accuracy. It follows with a discussion of an improvement in the instrument geometric model that correctssmall geometrical artifacts that appear in the along-scan direction. Finally, this paper discusses on-orbit measurements ofthe focal length and the impact of this on the scan-to-scan underlap/overlap.

We present high-resolution compressional wave to shear wave velocity ratios (Vp/Vs) beneath Kīlauea’s summit caldera by applying an in situ estimation method using waveform cross-correlation data for three similar earthquake clusters. We observe high Vp/Vs ratios (1.832 and 1.852) for two event clusters surrounded by the low background Vp/Vs value of 1.412 at ∼2.1 km depth below the surface. These high and low Vp/Vs ratios can be explained by melt- and CO2-filled cracks, respectively, based on a theoretical crack model. The event cluster with the highest Vp/Vs ratio consists of long-period events that followed the 1997 East Rift Zone eruption, indicating their association with fluid and magma movement. The depths of the two clusters with high Vp/Vs ratios are consistent with the magma reservoir location inferred from geodetic observations. Their locations east and north of Halema‘uma‘u crater suggest a horizontal extent of a few kilometers for the reservoir.

We combine classic and state-of-the-art techniques to characterize the seismic and volcanic features in the Coso area in southern California. Seismic tomography inversions are carried out to map the variations of Vp, Vs, and Vp/Vs beneath Coso. The velocities in the top layers of our model are correlated with the surface geological features. The Indian Wells Valley, with high silica content sediment strata, shows low-velocity anomalies up to 3 km depth, whereas the major mountain ranges, such as the south Sierra Nevada and the Argus Range, show higher velocities. The resulting three-dimensional velocity model is used to improve absolute locations for all local events between January 1981 and August 2011 in our study area. We then apply similar-event cluster analysis, waveform cross correlation, and differential time relocation methods to improve relative event location accuracy. A dramatic sharpening of seismicity patterns is obtained after using these methods. We also estimate high-resolution near-source Vp/Vs ratio within each event cluster using the differential times from waveform cross correlation. The in situ Vp/Vs method confirms the trend of the velocity variations from the tomographic results. An anomalous low-velocity body with low Vp, Vs, and Vp/Vs ratios, corresponding to the ductile behavior underlying the Coso geothermal field from 6 to 12 km depth, can be explained by the existence of frozen felsic magmatic materials with the inclusion of water. The material is not likely to include pervasive partial melt due to a lack of high Vp/Vs ratios.

We present a new three-dimensional seismic velocity model of the crustal and upper mantle structure for Mauna Loa and Kilauea volcanoes in Hawaii. Our model is derived from the first-arrival times of the compressional and shear waves from about 53,000 events on and near the Island of Hawaii between 1992 and 2009 recorded by the Hawaiian Volcano Observatory stations. The Vp model generally agrees with previous studies, showing high-velocity anomalies near the calderas and rift zones and low-velocity anomalies in the fault systems. The most significant difference from previous models is in V p/Vs structure. The high-Vp and high-V p/Vs anomalies below Mauna Loa caldera are interpreted as mafic magmatic cumulates. The observed low-Vp and high-V p/Vs bodies in the Kaoiki seismic zone between 5 and 15 km depth are attributed to the underlying volcaniclastic sediments. The high-Vp and moderate- to low-Vp/Vs anomalies beneath Kilauea caldera can be explained by a combination of different mafic compositions, likely to be olivine-rich gabbro and dunite. The systematically low-Vp and low-Vp/Vs bodies in the southeast flank of Kilauea may be caused by the presence of volatiles. Another difference between this study and previous ones is the improved Vp model resolution in deeper layers, owing to the inclusion of events with large epicentral distances. The new velocity model is used to relocate the seismicity of Mauna Loa and Kilauea for improved absolute locations and ultimately to develop a high-precision earthquake catalog using waveform cross-correlation data. ©2014. American Geophysical Union. All Rights Reserved.

An anomalous body with low Vp (compressional wave velocity), low Vs (shear wave velocity), and high Vp/Vs anomalies is observed at 8–11 km depth beneath the upper east rift zone of Kilauea volcano in Hawaii by simultaneous inversion of seismic velocity structure and earthquake locations. We interpret this body to be a crustal magma reservoir beneath the volcanic pile, similar to those widely recognized beneath mid-ocean ridge volcanoes. Combined seismic velocity and petrophysical models suggest the presence of 10% melt in a cumulate magma mush. This reservoir could have supplied the magma that intruded into the deep section of the east rift zone and caused its rapid expansion following the 1975 M7.2 Kalapana earthquake.

I present a reinvestigation of the seismic activity during an 11-mo-long seismic swarm between 1989 and 1990 beneath Mammoth Mountain in eastern California (United States). This swarm, believed to be the result of a shallow intrusion of magma beneath Mammoth Mountain, was followed by the emission of magmatic CO 2 gas, resulting in tree die-off in 1990 and posing a signifi cant human health risk around Mammoth Mountain. In this study, I apply a state-of-the-art approach to estimate the ratio of compressional- to shear-wave velocity (Vp/Vs) within similar event clusters using differential times from waveform crosscorrelation. A high-resolution three-dimensional seismic velocity model and a precise earthquake location catalog are obtained to complement the analysis of the in situ Vp/Vs ratios. The majority of the relocated seismicity below sea level is distributed in an anomalous body with low Vp and high Vp/Vs, consistent with the seismic expression of the magma body that triggered the seismic swarm. Abrupt changes in Vp/Vs ratios, with lower values for the shallow depths, are observed near sea level, indicating the source of the 1989 CO 2 fl ux is a shallow CO 2 reservoir instead of the hypothesized basaltic magma at mid-crustal depths of 10-25 km. From sea level to the surface, low Vp/Vs ratios in a near-vertical zone suggest involvement of fl uid in the upward-migration of the seismicity.

JOURNAL OF GEOPHYSICAL RESEARCH: SOLID EARTH, VOL. 118, 2275–2288, doi:10.1002/jgrb.50189, 2013 Systematic relocation of seismicity on Hawaii Island from 1992 to 2009 using waveform cross correlation and cluster analysis Robin S. Matoza, 1 Peter M. Shearer, 1 Guoqing Lin, 2 Cecily J. Wolfe, 3,4 and Paul G. Okubo 5 Received 28 November 2012; revised 8 April 2013; accepted 10 April 2013; published 20 May 2013. [ 1 ] The analysis and interpretation of seismicity from mantle depths to the surface play a key role in understanding how Hawaiian volcanoes work. We present results from a comprehensive and systematic re-analysis of waveforms from 130,902 seismic events recorded by the U.S. Geological Survey Hawaiian Volcano Observatory permanent seismic network from January 1992 to March 2009. We compute high-precision relative relocations for 101,390 events (77% of all events considered) using waveform cross correlation and cluster analysis, resulting in a multiyear systematically processed catalog of seismicity for all of Hawaii Island. The 17 years of relocated seismicity exhibit a dramatic sharpening of earthquake clustering along faults, streaks, and magmatic features, permitting a more detailed understanding of fault geometries and volcanic and tectonic processes. Our relocation results are generally consistent with previous studies that have focused on more specific regions of Hawaii. The relocated catalog includes crustal seismicity at Kilauea and its rift zones, seismicity delineating crustal detachment faults separating volcanic pile and old oceanic crust on the flanks of Kilauea and Mauna Loa, events along inferred magma conduits, and events along inferred mantle fault zones. The relocated catalog is available for download in the supporting information. Citation: Matoza, R. S., P. M. Shearer, G. Lin, C. J. Wolfe, and P. G. Okubo (2013), Systematic relocation of seismicity on Hawaii Island from 1992 to 2009 using waveform cross correlation and cluster analysis, J. Geophys. Res. Solid Earth, 118, 2275–2288, doi:10.1002/jgrb.50189. 1. Introduction [ 2 ] Seismic investigations began on Hawaii Island (Figure 1a) over 100 years ago [Jaggar, 1920], and a teleme- tered electronic seismic network was first installed in the late 1950s and has been steadily growing and improving ever since [Eaton and Murata, 1960; Klein and Koyanagi, 1980; Klein et al., 1987; Kauahikaua and Poland, 2012]. Additional supporting information may be found in the online version of this article. Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California, USA. Division of Marine Geology and Geophysics, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida, USA. Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, Hawaii, USA. Now at Earthquake Hazards Program, U.S. Geological Survey, Reston, Virginia, USA. Hawaiian Volcano Observatory, U.S. Geological Survey, Hawaii Volcanoes National Park, Hawaii, USA. Corresponding author: R. S. Matoza, Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0225, USA. (rmatoza@ucsd.edu) ©2013. American Geophysical Union. All Rights Reserved. 2169-9313/13/10.1002/jgrb.50189 The current network operated by the U.S. Geological Survey (USGS) Hawaiian Volcano Observatory (HVO) (Figure 1a) records approximately 5000–10,000 seismic events per year [Nakata, 2007; Nakata and Okubo, 2010]. Seismicity has played a central role in developing models of how Hawaiian volcanoes work [e.g., Eaton and Murata, 1960; Eaton, 1962; Klein et al., 1987; Ryan, 1988; Tilling and Dvorak, 1993; Wright and Klein, 2006; Got et al., 2008]. [ 3 ] Significant improvements in the relative loca- tion accuracy among nearby seismic events can be achieved without solving directly for the biasing effects of three-dimensional (3-D) velocity heterogeneity [e.g., Douglas, 1967; Frohlich, 1979; Frechet, 1985; Got et al., 1994; Shearer, 1997; Richards-Dinger and Shearer, 2000; Waldhauser and Ellsworth, 2000; Lin and Shearer, 2005]. Relative relocation can achieve high location precision using differential times obtained via waveform cross correla- tion [e.g., Frechet, 1985; Got et al., 1994; Fremont and Malone, 1987; Nadeau et al., 1995; Waldhauser et al., 1999; Shearer et al., 2005; Lin et al., 2007], in many cases collaps- ing diffuse seismicity to compact streaks aligned with fault slip [Rubin et al., 1999] or to planar surfaces reflecting fault planes [Got et al., 1994]. Relative relocation techniques have been used extensively to study seismicity on Hawaii Island; however, most studies have focused on subregions of the island or specific event sequences or types [e.g., Got et al., 1994; Gillard et al., 1996; Got and Okubo, 2003; Battaglia

Following the successful operations of the first Visible Infrared Imaging Radiometer Suite (VIIRS) instrument on-board the Suomi National Polar‐orbiting Partnership (SNPP) spacecraft since launch in October 2011, a second VIIRS instrument to be on-board the first Joint Polar Satellite System (JPSS-1) satellite has been fabricated, tested and integrated onto the spacecraft, readying for launch in 2017. The ground testing, including geometric functional performance testing and characterization, at the sensor level was completed in December 2014. Testing at the spacecraft level is on-going. The instrument geometric performance includes sensor (detector) spatial response, band-to-band coregistration (BBR), scan plane and pointing stability. The parameters have been calibrated and characterized through ground testing under ambient and thermal vacuum conditions, and numerical modeling and analysis. VIIRS sensor spatial response is measured by line spread functions (LSFs) in the scan and track directions for every detector. We parameterize the LSFs by: 1) dynamic field of view (DFOV) in the scan direction and instantaneous FOV (IFOV) in the track direction; and 2) modulation transfer function (MTF) for the 17 moderate resolution bands (M-bands) and for the five imagery bands (I-bands). We define VIIRS BBR for M-bands and I-bands as the overlapped fractional area of angular pixel sizes from the corresponding detectors in a band pair, including nested I-bands within the M-bands. The ground tests result in static BBR matrices. VIIRS pointing measurements include scan plane tilt and instrument-to-spacecraft mounting coefficients. This paper summarizes the pre-launch test results along with anomaly investigations. The pre-launch performance parameters will be tracked or corrected for as needed in on-orbit operations.

The γ-secretase complex, composed of presenilin, anterior-pharynx-defective 1, nicastrin, and presenilin enhancer 2, catalyzes the intramembranous processing of a wide variety of type I membrane proteins, including amyloid precursor protein (APP) and Notch. Earlier studies have revealed that nicastrin, a type I membrane-anchored glycoprotein, plays a role in γ-secretase assembly and trafficking and has been proposed to bind substrates. To gain more insights regarding nicastrin structure and function, we generated a conformation-specific synthetic antibody and used it as a molecular probe to map functional domains within nicastrin ectodomain. The antibody bound to a conformational epitope within a nicastrin segment encompassing residues 245–630 and inhibited the processing of APP and Notch substrates in in vitro γ-secretase activity assays, suggesting that a functional domain pertinent to γ-secretase activity resides within this region. Epitope mapping and database searches revealed the presence of a structured segment, located downstream of the previously identified DAP domain ( D YIGS a nd p eptidase; residues 261–502), that is homologous to a tetratricopeptide repeat (TPR) domain commonly involved in peptide recognition. Mutagenesis analyses within the predicted TPR-like domain showed that disruption of the signature helical structure resulted in the loss of γ-secretase activity but not the assembly of the γ-secretase and that Leu571 within the TPR-like domain plays an important role in mediating substrate binding. Taken together, these studies offer provocative insights pertaining to the structural basis for nicastrin function as a “substrate receptor” within the γ-secretase complex.

We obtain a seismic velocity model of the California crust and uppermost mantle using a regional-scale double-difference tomography algorithm. We begin by using absolute arrival-time picks to solve for a coarse three-dimensional (3D) P velocity ( V P ) model with a uniform 30 km horizontal node spacing, which we then use as the starting model for a finer-scale inversion using double-difference tomography applied to absolute and differential pick times. For computational reasons, we split the state into 5 subregions with a grid spacing of 10 to 20 km and assemble our final statewide V P model by stitching together these local models. We also solve for a statewide S -wave model using S picks from both the Southern California Seismic Network and USArray, assuming a starting model based on the V P results and a V P / V S ratio of 1.732. Our new model has improved areal coverage compared with previous models, extending 570 km in the SW–NE direction and 1320 km in the NW–SE direction. It also extends to greater depth due to the inclusion of substantial data at large epicentral distances. Our V P model generally agrees with previous separate regional models for northern and southern California, but we also observe some new features, such as high-velocity anomalies at shallow depths in the Klamath Mountains and Mount Shasta area, somewhat slow velocities in the northern Coast Ranges, and slow anomalies beneath the Sierra Nevada at midcrustal and greater depths. This model can be applied to a variety of regional-scale studies in California, such as developing a unified statewide earthquake location catalog and performing regional waveform modeling.

We use relative arrival times and locations for similar earthquake pairs that are found using a cross-correlation method to analyze the time dependence of P and S station terms in southern California from 1984 to 2002. We examine 494 similar event clusters recorded by Southern California Seismic Network (SCSN) stations and compute absolute arrival-time variations from the differential arrival-time resi- duals obtained following event relocation. We compute station terms from the robust means of the absolute arrival-time residuals from all events recorded by each station at 3-month intervals. We observe nine stations with abrupt offsets in timing of 20- 70 msec, which are likely caused by equipment changes during our study period. Taking these changes into account could improve the relative location accuracy for some of the event clusters. For other stations, we generally do not see systematic temporal variations greater than about 10 msec. Analysis of residuals along individual ray paths does not reveal any clear localized regions of apparent velocity changes at depth. These results limit large-scale, long-lasting temporal variations in P and S ve- locities across southern California during this time period to less than about � 0:2%. However, there is an increased fraction of individual travel-time residuals exceeding 20 msec immediately following major earthquakes from source regions near the main- shock rupture.

There is growing evidence that the two small leucine-rich proteoglycans biglycan and decorin regulate the assembly of connective tissues and alter cell behavior during development and pathological processes. In this study, we have used an experimental animal model of unilateral ureteral ligation and mice deficient in either biglycan or decorin. We discovered that pressure-induced injury to the wild-type kidneys led to overexpression of decorin, biglycan, fibrillin-1, and fibrillin-2. In contrast, in biglycan-deficient kidneys the overexpression of fibrillin-1 was markedly attenuated and this was associated with cystic dilatation of Bowman’s capsule and proximal tubules. Notably, we found that in ligated kidneys from decorin-null mice, fibrillin-1 expression was initially enhanced to the same extent as in wild-type animals. However, long-term obstruction resulted in down-regulation of fibrillin-1 and concurrent cystic dilatation of Bowman’s capsule in 33% of kidneys at 5 months after obstruction. In all of the genotypes, no differences in fibrillin-2 expression were observed. These in vivo data correlated with a significant induction of fibrillin-1 expression in renal fibroblasts and mesangial cells by recombinant biglycan and decorin. Our results indicate a novel role for decorin and biglycan during pressure-induced renal injury by stimulating fibrillin-1 expression.

Mutations in fibrillin-1 lead to Marfan syndrome and some related genetic disorders. Many of the more than 600 mutations currently known in fibrillin-1 eliminate or introduce cysteine residues in epidermal growth factor-like modules. Here we report structural and functional consequences of three selected cysteine mutations (R627C, C750G, and C926R) in fibrillin-1. The mutations have been analyzed by means of recombinant polypeptides produced in mammalian expression systems. The mRNA levels for the mutation constructs were similar to wild-type levels. All three mutated polypeptides were secreted by embryonic kidney cells (293) into the culture medium. Purification was readily feasible for mutants R627C and C750G, but not for C926R, which restricted the availability of this mutant polypeptide to selected analyses. The overall folds of the mutant polypeptides were indistinguishable from the wild-type as judged by the ultrastructural shape, CD analysis, and reactivity with a specific antibody sensitive for intact disulfide bonds. Subtle structural changes caused by R627C and C750G, however, were monitored by proteolysis and heat denaturation experiments. These changes occurred in the vicinity of the mutations either as short range effects (R627C) or both short and long range effects (C750G). Enhanced proteolytic susceptibility was observed for R627C and C750G to a variety of proteases. These results expand and further strengthen the concept that proteolytic degradation of mutated fibrillin-1 might be an important potential mechanism in the pathogenesis of Marfan syndrome and other disorders caused by mutations in fibrillin-1.

In this paper, nano-irons were successfully synthesized by Suaeda salsa extraction (SSE) and properties of the nano-iron particles were studied. Results of scanning electron microscopy (SEM) showed that the average of particle size of nano-iron particles were about 23~53 nm. In addition, the selected area electron diffraction (SAED) and X-ray diffraction (XRD) indicated that most of the synthesized nanoparticles were amorphous, but only a few were crystalline. Moreover, energy dispersive spectrometer (EDS) and fourier transform infrared spectroscopy (FTIR) reflected that the nano-iron particles were coated with organic substances containing O-H, C=C, C-N and other functional groups, which were as reducing agents and stabilizers during the synthesis of nano-iron particles. At 25°C, when the dosage of nano-irons was 1.0 g/L and the initial concentration of Cr(VI) was 5 mg/L, the removal rate of Cr(VI) could reach 100% in 5 minutes.