Hebei Seismological Bureau

Over the last two decades, multiple classifier system (MCS) or classifier ensemble has shown great potential to improve the accuracy and reliability of remote sensing image classification. Although there are lots of literatures covering the MCS approaches, there is a lack of a comprehensive literature review which presents an overall architecture of the basic principles and trends behind the design of remote sensing classifier ensemble. Therefore, in order to give a reference point for MCS approaches, this paper attempts to explicitly review the remote sensing implementations of MCS and proposes some modified approaches. The effectiveness of existing and improved algorithms are analyzed and evaluated by multi-source remotely sensed images, including high spatial resolution image (QuickBird), hyperspectral image (OMISII) and multi-spectral image (Landsat ETM+). Experimental results demonstrate that MCS can effectively improve the accuracy and stability of remote sensing image classification, and diversity measures play an active role for the combination of multiple classifiers. Furthermore, this survey provides a roadmap to guide future research, algorithm enhancement and facilitate knowledge accumulation of MCS in remote sensing community.

We present the results of mapping selected cross-sections across the margins of the Chinese Tien Shan, an intracontinental mountain belt that formed in response to the India-Eurasia collision. This belt contains significant lateral variation in topography, structure, and stratigraphy at all scales, and our estimated rates of shortening also reveal a distribution of shortening that varies laterally. At the largest scale, it consists of two major high mountain ranges in the west that merge eastward into a complex, single high mountain belt with several distinct ranges, then separates farther eastward into several low mountain ranges in the south and a single narrow high mountain range in the north. Active fold-and-thrust belts along parts of the north and south flanks of the Tien Shan involve only Mesozoic and Cenozoic sedimentary cover, which varies in both stratigraphy and structure from east to west. The southern fold-and-thrust belt decreases in width and complexity from west to east and ends before reaching Korla. The northern belt begins near the longitude where the southern belt ends, and increases in width and complexity from west to east. Within these two fold-and-thrust belts are both E-W and N-S variations in stratigraphy at the scale of the fold-and-thrust belts and across individual structures. All these variations make it very difficult to generalize either structure or stratigraphy within the Tien Shan or within local areas. Four maps and cross-sections, two across each of the northern and southern fold-and-thrust belts, imply different magnitudes of shortening. In the eastern part of the northern belt, a cross-section along the southern part of the Hutubi River yields shortening of 6.2 km, and a section to the north across the Tugulu anticline yields shortening of 5.5 km. The two parts of the cross-section cannot be added because the Tugulu anticline lies 20 km west of the Hutubi River, and diminishes greatly in amplitude toward the Hutubi River. In the western part of the northern belt, cross-sections require 4.6 to 5.0 km of shortening at Tuositai and 2.12 to 2.35 km across the Dushanzi anticline. The Tuositai structure lies south of the Dushanzi anticline, but shortening in these two areas also cannot be summed, because they seem to be separated by a N-trending strike-slip fault. In the western part of the southern fold-and-thrust belt, an incomplete cross-section along the Kalasu River suggests shortening of 12.1 to 14.1 km. If the estimated shortening of 6 to 7 km in the Qiulitage anticline, which we did not map, is added, the total shortening in this cross-section would be ∼18 to 21 km. To the east, a complete cross-section at Boston Tokar yielded shortening of 10.3 to 13.0 km. Calculating long-term shortening rates from these four cross-sections is difficult, because the time of initiation of deformation is poorly known. In the Kalasu River area of the southern belt, there is evidence that limited shortening of 2 to 4 km occurred in the early Miocene, if major thickness changes in deposition of conglomerate unit 3b are interpreted to be growth strata. Geological evidence suggests that most of the shortening began in both belts after the beginning of the deposition of the thick conglomerate unit shown as lower Quaternary on Chinese geological maps. Strata within the middle part of these conglomerates were deposited during the growth of the folds. Presence of Equus near the base of similar conglomerates indicates a Quaternary age, but the fossil localities are far from most of our cross-sections, and the contemporaneity of the rocks remains in question. The beginning of conglomerate deposition may be controlled by climate change, and if so, the beginning of conglomerate deposition may be generally contemporaneous throughout the region at ∼2.5 Ma. Deformation began at some time after the onset of conglomerate deposition, but this time is not well constrained. Thus we have calculated shortening rates for 2.5, 1.6, and 1.0 Ma that should bracket maximum and minimum slip rates. These calculations yield the following ranges in the northern fold-and-thrust belt: southern Hutubi River = 2.5 to 6.2 mm/yr; Tugulu anticline = 2.1 to 5.5 mm/yr; Tuositai anticline = 1.8–2.0 to 4.6–5.0 mm/yr; and Dushanzi anticline = 0.8 to 2.1–2.4 mm/yr; and in the southern fold-and-thrust belt: Kalasu River = 4.6–5.6 (including the Qiulitage anticline = 7.2–8.4) to 12.1–14.1 (including Qiulitage anticline = 18–21) mm/yr; and at Boston Tokar = 4.1–5.2 to 10.3–13.1 mm/yr. If 2 to 4 km of shortening occurred in the Kalasu River section during early Miocene time, the long-term rates for Quaternary time are 3.2–4.8 (including Qiulitage anticline = 5.6–7.6) to 8.1–12.1 (including Qiulitage anticline = 14–19) mm/yr. Calculation of the shortening rate across the entire width of the Tien Shan is difficult because of the rapid lateral variations in structure and because of active deformation within the range, which we have not studied. The cross-sections at Boston Tokar in the south and Tuositai in the north lie along the same longitude. Adding the shortening rates in these areas would yield a minimum range (using 2.5 Ma as the initiation time) of 5.7 to 7.2 mm/yr. If deformation began at 1.6 or 1.0 Ma, the range of shortening rates would be 10–11.2 mm/yr to 14.9–18.1 mm/yr, respectively. Because the first indication of structural growth with the mapped areas occurs above the base of the conglomerates at the top of the stratigraphic succession, a minimum shortening rate greater than 5.7 to 7.2 mm/yr is more likely. Both the marginal fold-and-thrust belts have a thin-skinned geometry with the drcollement at -6 to 10 km and within Mesozoic and Cenozoic sedimentary rocks. Toward the interior of the range the decollement must pass into the Paleozoic basement rocks and steepen beneath the flanks of the range. The structural style is similar to that in the Laramide Rocky Mountains and the California Transverse Ranges. The highest parts of the Tien Shan are adjacent to areas of active shortening. Such a relation might suggest that the major uplift of the Tien Shan is very young, mostly latest Cenozoic or Quaternary in age. The shortening across the Tien Shan is inhomogeneous and spatially distributed.

Abstract We collected continuous seismic data recorded between 2007 and 2010 by 208 broadband stations from the Chinese Provincial Digital Seismic Networks, A Seismic Collaborative Experiment of Northern Tibet, and the Northeastern Tibet Seismic experiment. Cross correlations of vertical component records are computed to extract the Rayleigh wave empirical Green's functions. Group and phase velocities are then constructed from the empirical Green's functions in 8 to 50 s period. At periods ≤25 s, more than 10% lower velocities are imaged beneath the Qaidam Basin, and high velocities are observed beneath the nonbasin regions. At periods ≥30 s, up to 10% lower velocities are imaged in the Qiangtang and Songpan‐Ganze Terranes. From these group and phase velocity maps, a three‐dimensional (3‐D) V sv model of the crust is derived. The model shows that the Qiangtang and Songpan‐Ganze Terranes have a very thick crust with a prominent low‐velocity zone (LVZ) in the middle crust. The LVZ thins out in the vicinity of the eastern Kunlun Mountains, providing a new constraint on the mode of deformation across the Tibetan Plateau. The northwestern Qilian Orogen, where receiver functions reveal a Moho deeper than the surrounding areas, also features a relatively weak midcrustal LVZ, which we interpret as an intracrustal response associated with the shortening between the North China Craton and the Tibetan Plateau.

ABSTRACT Recent work on retrieving the Green’s function with the Marchenko equation shows how these functions for a virtual source in the subsurface can be obtained from reflection data. The response to the virtual source is the Green’s function from the location of the virtual source to the surface. The Green’s function is retrieved using only the reflection response of the medium and an estimate of the first arrival at the surface from the virtual source. Current techniques, however, only include primaries and internal multiples. Therefore, all surface-related multiples must be removed from the reflection response prior to Green’s function retrieval. We have extended the Marchenko equation to retrieve the Green’s function that includes primaries, internal multiples, and free-surface multiples. In other words, we have retrieved the Green’s function in the presence of a free surface. The information needed for the retrieval is the same as the current techniques, with the only difference being that the reflection response now also includes free-surface multiples. The inclusion of these multiples makes it possible to include them in the imaging operator, and it obviates the need for surface-related multiple elimination. This type of imaging with Green’s functions is called Marchenko imaging.

Pan evaporation (Epan) is an important indicator of regional evaporation intensity and degree of drought. However, although more evaporation is expected under rising temperatures, the reverse trend has been observed in many parts of the world, known as the “pan evaporation paradox”. In this paper, the Haihe River Basin (HRB) is divided into six sub-regions using the Canopy and k-means (The process for partitioning an N-dimensional population into k sets on the basis of a sample is called “k-means”) to cluster 44 meteorological stations in the area. The interannual and seasonal trends and the significance of eight meteorological indicators, including average temperature, maximum temperature, minimum temperature, precipitation, relative humidity, sunshine duration, wind speed, and Epan, were analyzed for 1961 to 2010 using the trend-free pre-whitening Mann-Kendall (TFPW-MK) test. Then, the correlation between meteorological elements and Epan was analyzed using the Spearman correlation coefficient. Results show that the average temperature, maximum temperature, and minimum temperature of the HRB increased, while precipitation, relative humidity, sunshine duration, wind speed and Epan exhibited a downward trend. The minimum temperature rose 2 and 1.5 times faster than the maximum temperature and average temperature, respectively. A significant reduction in sunshine duration was found to be the primary factor in the Epan decrease, while declining wind speed was the secondary factor.

Abstract High-quality focal mechanisms within the Taiwan Seismic Network are determined utilizing first motions, SH/P amplitude ratios, and hypocentral locations obtained in a joint tomographic inversion. The small-to-moderate (2.7 ≦ ML ≦ 5.7) events, ranging in depths from 3 to 43 km, occurred in the area where mountain building is taking place. The data used were recorded between March 1991 and July 1994. Of the 97 earthquakes studied, the focal mechanisms of 23 of these determined on the basis of a 3D velocity model are remarkably different from the routine 1D results. In order to correct for the effect of attenuation on P- and S-wave amplitudes, QP and QS are determined using the spectral ratio method. QP ranges from 289 to 330 and QS from 201 to 301. The SH/P amplitude ratios are found to be very effective as constraints for choosing the best solutions among those consistent with the polarities. The resulting focal mechanisms show a high degree of variability across the island, but in terms of tectonic stress regimes, they show consistent patterns. They provide a glimpse of the mechanical processes under the Taiwan orogen.

Extracellular vesicles (EVs) generated from mesenchymal stem cells (MSCs) play an essential role in modulating cell-cell communication and tissue regeneration. The clinical translation of EVs is constrained by the poor yield of EVs. Extrusion has recently become an effective technique for producing a large scale of nanovesicles (NVs). In this study, we systematically compared MSC NVs (from extrusion) and EVs (from natural secretion). Proteomics and RNA sequencing data revealed that NVs resemble MSCs more closely than EVs. Additionally, microRNAs in NVs are related to cardiac repair, fibrosis repression, and angiogenesis. Lastly, intravenous delivery of MSC NVs improved heart repair and cardiac function in a mouse model of myocardial infarction. Electronic Supplementary Material: Supplementary material (Figs. S1-S4) is available in the online version of this article at 10.1007/s12274-023-5374-3.

To accurately understand soil environmental quality and improve the problem of the traditional method, which is that it has a single evaluation factor and cannot reflect the overall condition of the soil, a complex geological soil heavy metal evaluation modeling method based on the Nemerow index method is proposed. Index evaluation methods, ArcGIS technology, and a human health risk assessment were carried out to obtain the spatial distribution of heavy metals in the soil and the current status of pollution accumulation. The comprehensive pollution index (CPI) method, geo-accumulation index (GAI) method, and potential ecological hazard (PEH) index were adopted to analyze the pollution degree of soil heavy metals. On this basis, the Nemerow index method was used to establish a complex geological soil heavy metal evaluation model, and the standard Nemerow index was calculated to complete the evaluation of heavy metal pollution in complex geological soils. The research results showed that this method could make the evaluation factors obtain reasonable scores and obtain more reasonable soil evaluation results.

The multiscale noise in the 3D point cloud data of rock surfaces which collected by 3D scanners has a significant influence on the exploration of rock surface morphology. To this end, this paper proposes a multiscale noise removal overall filtering algorithm. The specific processing procedure of the algorithm is as follows. First, a weighted principal component analysis is performed on point cloud data, i.e., the neighboring point distance is used as a weight in the principal component analysis, the covariance feature matrix of the weighted point is estimated, and the eigenvector corresponding to the lowest eigenvalue is used as the normal vector of the point cloud data. Second, in the weighted principal component analysis, estimating three eigenvalues corresponding to the Eigen matrix of the point cloud data, the ratio of the eigenvalue corresponding to the normal vector to the sum of three eigenvalues is used as the surface change factor. For the sample point, if the surface change factor of one sample point is less than the average value of the surface change factor of all sample points in the neighborhood, the sample point belongs to a flat area; otherwise, it belongs to a mutation area. Finally, in order to achieve multiscale noise removal, statistical filtering algorithm is used to remove large scale noise in flat area, additionally bilateral filtering algorithm is adopted to remove small scale noise in mutation area. In the experiments, the improved principal component analysis is combined with the overall filtering algorithm to accurately estimate the eigenvalues of the point cloud data points. After that, the eigenvalues of the sample points are used to distinguish between flat area and mutation area, so as to consider large scale noise and small scale noise. From the experimental results, it can be seen that overall filtering algorithm can consider both large scale and small scale noise and can remove noise from the point cloud data of rock samples. Visual judgment, normal distribution and fractal distribution tests are employed on filtered rock sample point cloud data to verify the reliability of the filtering results.

Modified β-cyclodextrin and <italic>N</italic>-phenethyl-methacrylamide were utilized to react with acrylamide and acrylic acid to synthesize hydrophobically associating polyacrylamide (HMPAM) <italic>via</italic> photoinitiated free-radical micellar copolymerization.

The Indochina block is important to our understanding of the extrusion model as a consequence of the Indo-Eurasia collision. The lithospheric structure of this block, however, remains obscured due to a lack of sufficient instrumentation for high resolution seismic imaging. We present a shear velocity model derived from Rayleigh wave phase velocity tomography using data from recently deployed seismic networks in this region. Our inversion results for lithospheric structure show strong correlations with tectonic history in this block. A prominent slow-velocity anomaly (5 per cent) is observed in northern Indochina along the Ailao Shan-Red River (ASRR) shear zone including Chuxiong basin, Lanping-Simao fold belt and Thailand rift basin, which has seen extensive deformation events since Eocene. The Khorat Plateau basin is characterized by thick continental keel type lithosphere, consistent with palaeomagnetic and geological observations indicating this basin has experienced much less deformation than the surrounding regions. Additionally, our inversion imaged a sharp, lithospheric-scale velocity contrast across the southeastern segment of ASRR, indicative of a thin and thus relatively weak lithosphere southwest of Red River Fault. The thin lithosphere, low asthenospheric seismic velocities we observe and the average crustal thicknesses in the region suggest that the topography high is dynamically supported by upwelling asthenosphere rather than thickening of the crust/lithosphere. Based on the occurrence of Palaeogene volcanism and its timing, we prefer an explanation of thinning of the lithosphere and allowing a throughgoing fault rather than emplacement of a thin terrane to explain the thin lithosphere. Therefore, the anomalously thin lithosphere between Khorat Plateau and the ASRR in conjunction with other geological observations is generally consistent with the extrusion model for Indochina, which requires localization of lithospheric deformation around tectonic blocks.

Abstract We examine the feasibility of high-resolution microseismic imaging of unconventional reservoirs. Given frequencies in typical downhole microseismic data that are almost an order of magnitude higher than in seismic reflection data, a comparable increase in image resolution might be expected, bringing potential resolution of downhole microseismic images to a few meters. We demonstrate that such a resolution is indeed achievable and present two case studies illustrating the reservoir features that can be imaged. Our first example, constructed with P-waves recorded in the Woodford Field, reveals internal fabric of the Woodford reservoir and formations surrounding it, allowing us to discriminate the stimulated and unstimulated zones of the Lower Woodford Shale. Encouraged by those results, in our second example, this time from the Bakken Field, we use the slow shear waves, which are more sensitive to fluids than P-waves, to find out whether hydraulic fractures themselves could be imaged. Our seismic volume contains peculiar geobodies, growing precisely from perforation holes spaced at a 40 ft interval in a treatment well landed in the Middle Bakken. These geobodies penetrate through the Lower Bakken Shale reservoir and terminate at the top of the Three Forks dolomites. While our interpretation of the extracted geobodies as hydraulic fractures remains an interpretation, the remarkably high resolution of seismic images obtained in both case studies is unquestionable.

Abstract It is known that clustered small earthquakes often occur in the fault plane vicinities of large earthquakes. Based on the simulated annealing and Gauss‐Newtonian nonlinear inversion algorithms, we develop a robust algorithm to estimate fault plane parameters of strong earthquakes such as strike, dip, and location using data of densely populated small events. Rake angle of the fault plane is further inferred from regional tectonic stress parameters. This method can also be employed for determination of fault plane parameters of an active fault using data of densely populated small earthquakes. We apply the algorithm to investigate the fault planes of the 1976 Tangshan, Luanxian, and Ninghe earthquakes and the Lulong fault, using precisely relocated earthquakes which occurred near the earthquake rupture zone between 1 April 2002 and 31 May 2006, and obtain the parameters of strike, dip, location, and rake angle of these fault planes. Our estimated fault planes are close to the results of previous studies, attesting the validity of our method. In addition, we discover an aligned seismic belt east of the Luanxian seismic zone trending NE‐SW, which can be ascertained as a fracture zone. The faulting parameters of the fracture zone such as the strike, dip and rake are determined accurately. It is still an open question whether the Luanxian and Ninghe faults have ruptured during the Tangshan earthquake sequence, answers to the question await for further multi‐disciplinary studies and bear great significance for the understanding of dynamic processes of the Tangshan earthquake sequence.

The AlkB homologs ( ALKBH ) gene family regulates N 6 -methyladenosine (m 6 A) RNA methylation and is involved in plant growth and the abiotic stress response. Poplar is an important model plant for studying perennial woody plants. Poplars typically have a long juvenile period of 7–10 years, requiring long periods of time for studies of flowering or mature wood properties. Consequently, functional studies of the ALKBH genes in Populus species have been limited. Based on AtALKBHs sequence similarity with Arabidopsis thaliana , 23 PagALKBHs were identified in the genome of the poplar 84K hybrid genotype ( P. alba × P. tremula var. glandulosa ), and gene structures and conserved domains were confirmed between homologs. The PagALKBH proteins were classified into six groups based on conserved sequence compared with human, Arabidopsis, maize, rice, wheat, tomato, barley, and grape. All homologs of PagALKBHs were tissue-specific; most were highly expressed in leaves. ALKBH9B and ALKBH10B are m 6 A demethylases and overexpression of their homologs PagALKBH9B and PagALKBH10B reduced m 6 A RNA methylation in transgenic lines. The number of adventitious roots and the biomass accumulation of transgenic lines decreased compared with WT. Therefore, PagALKBH9B and PagALKBH10B mediate m 6 A RNA demethylation and play a regulatory role in poplar growth and development. Overexpression of PagALKBH9B and PagALKBH10B can reduce the accumulation of H 2 O 2 and oxidative damage by increasing the activities of SOD, POD, and CAT, and enhancing protection for Chl a/b, thereby increasing the salt tolerance of transgenic lines. However, overexpression lines were more sensitive to drought stress due to reduced proline content. This research revealed comprehensive information about the PagALKBH gene family and their roles in growth and development and responsing to salt stress of poplar.

Climate warming, a serious environmental problem worldwide, is considered a major threat to aquatic ecosystems. A primary feature of climate warming is elevated temperatures which in shallow aquatic ecosystems might affect competition for light and nutrient between benthic algae on the sediment surface and planktonic algae in the water. The outcomes of such competition would not only affect the distribution of primary production, but also determine the fundamental character of shallow aquatic habitats as clear water or turbid water systems. We conducted a mesocosm study to evaluate the effects of elevated temperature on competition between planktonic algae and benthic algae for light and nutrients. We found that elevated temperature increased the concentrations of total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) in overlying water and enhanced the growth of planktonic algae (measured as chlorophyll a , Chl a ), but decreased light intensity and benthic algal biomass (Chl a ). Our results indicate that elevated temperature can increase the growth of planktonic algae and enhance their competitive advantage over the benthic algae in shallow lakes, thereby contributing to eutrophication and a decline in water quality. These findings shed further light on the effects of global warming on aquatic ecosystems.

The acquisition of 2-50 Hz low-frequency vibration signals is of great significance for the monitoring researches on engineering seismology, bridges & dams, oil & gas exploration, etc. A multi-cantilever beam low-frequency FBG acceleration sensor is proposed against the low sensitivity that predominates in the low-frequency vibration measurement by FBG acceleration sensors. Structural parameters of the sensor is subjected to simulation analysis and optimization design using the ANSYS software; the real sensor is developed based on the simulation results in the following manner: Three rectangular of the cantilever beams are evenly arranged around the mass block at 120°to improve the sensitivity and alleviate the transverse crosstalk of sensor; in the end, a performance test is performed on the sensor. According to the research findings, the sensor, whose natural frequency is approximately 64 Hz, is applicable for monitoring the low-frequency vibration signals within the range 16-54 Hz. The sensor sensitivity is approximately [Formula: see text], the linearity being greater than 99%, the transverse interference immunity being lower than 2.58%, and the dynamic range being up to 86 dB. The findings offer a reference for developing sensor of the same type and further improving the sensitivity of fiber optic acceleration sensor.

BACKGROUND: Transmission over the Internet of low-resolution images acquired by automated screening of cervical cytology specimens has the potential to provide remote interpretation and, hence, centralization of a cytology workforce. METHODS: Liquid-based cervical cytology slides were scanned using the FocalPoint(R) System. Ten black-and-white images that had the greatest probability of containing abnormality were acquired from each of 32 reference slides (16 negative samples, 3 samples of atypical squamous cells of uncertain significance, 5 samples of low-grade squamous intraepithelial lesions [LSIL], 5 samples of high-grade squamous intraepithelial lesions [HSIL], 1 adenocarcinoma in situ sample, and 2 carcinoma samples) and were transmitted as e-mail attachments in JPEG format to remote reading stations. The slides were interpreted independently by two pathologists and were assigned to either of two groups: 1) suspicious for >or=HSIL or 2) <or=LSIL. The interpretations were compared with the reference diagnoses. The specimens were then randomized, and the image sets were redistributed to the pathologists for another round of interpretation and scoring. RESULTS: The initial and subsequent trials yielded similar results. Pooling the interpretations of the two pathologists, the concordance rate between reference and assigned diagnostic groups for each of the two trials was 84%, the false-positive rate was 8.3%, and the false-negative rate was 37.5%. Review of the discrepant slides revealed subtle cellular changes that may be utilized to reduce errors and, with training, to optimize sensitivity and specificity. CONCLUSIONS: This procedure showed promise for allowing remote interpretation of device-selected images. The procedure may represent an effective way to centralize cervical cytology services and to allow the provision of services to previously unscreened populations that lack an effective cytology infrastructure.

Abstract. The coupled atmospheric–hydrologic modeling system is an effective way to improve the accuracy of rainfall–runoff modeling and extend the lead time in real-time flood forecasting. The aim of this study is to explore the appropriate coupling scale of the coupled atmospheric–hydrologic modeling system, which is established by the Weather Research and Forecasting (WRF) model and the gridded Hebei model with three different sizes (1 km×1 km, 3 km×3 km and 9 km×9 km). The Hebei model is a conceptual rainfall–runoff model designed to describe a mixed runoff generation mechanism, including both storage excess and infiltration excess, in the semi-humid and semi-dry area of northern China. The soil moisture storage capacity and infiltration capacity of different grids in the gridded Hebei model are obtained and dispersed using the topographic index. The lumped Hebei model is also used to establish the lumped atmospheric–hydrologic coupled system as a reference system. Four 24 h storm events occurring at two small- and medium-scale sub-watersheds in northern China are selected as case studies. Contrastive analyses of the flood process simulations from the gridded and lumped systems are carried out. The results show that the flood simulation results may not always be improved with higher-dimension precision and more complicated system, and the grid size selection has a strong relationship with the rainfall evenness. For the storm events with uniform spatial distribution, the coupling scale has less impact on flood simulation results, and the lumped system also performs well. For the storm events with uneven spatiotemporal distribution, the corrected rainfall can improve the simulation results significantly, and higher resolution leads to better flood process simulation. The results can help to establish the appropriate coupled atmospheric–hydrologic modeling system to improve the flood forecasting accuracy.

Abstract N6-methyladenosine (m 6 A) is abundant in the mammalian brain and is considered to have a wide range of effects on learning and memory. Here, we found that the upregulated methyltransferase-like protein 16 (METTL16) in the hippocampal tissues of Morris water maze (MWM)-trained mice contributed to improved memory formation and hippocampal synaptic plasticity. Mechanismly, METTL16 promoted the expression of methionine adenosyltransferase 2A (MAT2A) by the m 6 A methylation of the MAT2A mRNA-3′UTR-end to increase its stability, and this involved in improving hippocampal global m 6 A levels, plasticity of dendritic spine, learning and memory. This study provides a new perspective to explore the regulatory mechanisms of m 6 A for learning and memory.

ABSTRACT A recently proposed paraxial ray-based technique for relative location of microseismicity is extended to accommodate several master events with respect to which other events, termed the slaves, are located. The multi-master extension addresses two issues inherent for the existing single-master algorithm: a gradual decrease of its accuracy with the distance from the master and less than satisfactory performance in the presence of strong velocity heterogeneity. Those deficiencies are handled by applying an improved paraxial traveltime formula, exact in homogeneous elliptically anisotropic media, and by distributing masters in the subsurface to sample its heterogeneity. The contributions of different master events to the hypocenter of a given slave are automatically weighted to enhance the influence of adjacent masters, ensuring the precise slave location, and to suppress distant ones, tending to increase the slave-location errors. Tests of the multi-master relative event-location method on synthetic and field microseismic data demonstrate its precision and flexibility as well as applicability to both surface and downhole microseismic geometries.