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Elastic reverse time migration is currently an advanced imaging method in the petroleum industry. Generally, we use a finite difference algorithm to discretize forward-propagated wavefield and the back-propagated wavefield , then obtain the final image profile through cross-correlation imaging conditions . To overcome the numerical dispersion of elastic reverse time migration, one all-new strategy proposed in our letter, we design a kind of residual learning network of deep CNN for the seismic date to correct the dispersion of lower order finite difference operator, that is, both for seismic receiver data and wavefields data . In the process of elastic reverse time migration, we modify the numerical dispersion of forward-propagated wavefield, back-propagated wavefield and receiver data respectively, and then calculate the cross-correlation to obtain a more accurate image of underground structure . Residual learning and bath normalization were used to improve the trained seismic network . The test verified that our algorithm is more accurate when compared with the original finite difference method.

The Surgical procedure of cesarean section (CS) causes a large wound that any delay in its healing could increase the rate of stress, inconvenience, and dissatisfaction among the women who underwent CS procedure about six weeks after childbirth. The present study is trying to evaluate the effect of alginate and gelatin hydrogel composited with nanozinc effective extensibility and compressibility as a wound dressing nursing care after CS. The number of participants was 700 individuals enrolled all who underwent C-sections at Medical College in the Second Affiliated Hospital of Xi’an Jiaotong University (from September 2017 until September 2020). Patients were divided into two groups of case and control consist of 350 cases. The case group was treated with alginate gelatin hydrogel-nZnO+antibacterial wound dress and the control group was treated with wound healing ordinary creams+antibacterial. Three and four weeks following CS, the healing process of the wound was evaluated using REEDA wound scale. In the current study, there was not any significant difference between the studied case and control group in respect to individual’s demographical characteristics such as economic status, educational level, BMI, and age. (P > 0.05). Also, we observed that patients treated with alginate gelatin hydrogel-nZnO would experience a significantly lower score for redness, ecchymosis, edema, and approximation of CS wound in comparison to the control group (P < 0.05). Also, slope analysis showed that the healing process was significantly quicker in patients treated with alginate gelatin hydrogel-nZnO in comparison to the control group. Finally, it was observed that more than 80% of patients did not represent any major sign of CS after three weeks, however, in the control case this issue was estimated at 50.6%. No allergic reaction has been observed. Our results showed that using alginate gelatin hydrogel-nZnO wound dress could be a novel treatment in a nursing care setting to decrease the CS wound complication and increase the healing process without any allergic reaction.

Three-dimensional (3D) marine gravity field plays an important role in many practical applications, such as matching navigation, object monitoring and resource exploitation. However, the accuracy of gravity field generated by most existing methods is relatively low. To solve this problem, this study innovatively put forwards a new method for establishing high-accuracy 3D marine gravity field by using a joint inversion algorithm. The presented method incorporates gravity fields observed at different altitudes, especially those observed near the seafloor, because they contain more prominent short-wavelength signals of the sources. The final joint inversion formulas are developed from the standard form of independent inversion of single gravity data sets, so it is conducive to include different weighting matrices. To achieve efficiency of the presented method, the nonlinear objective function is minimized iteratively using a fast randomized singular value decomposition (RSVD) technique. The employing of RSVD also facilitates the determination of an optimal regularization parameter based on the generalized cross-validation criterion. The presented method is tested on both synthetic gravity fields simulated by a theoretical density model and real gravity fields collected in the South China Sea. Numerical results demonstrate that the presented method can provide more accurate 3D gravity fields than the commonly used iterative downward continuation method in wavenumber domain (DCW) and the conventional equivalent source (CES) method.

Purpose. To delineate the clinical and genetic characteristics of Chinese patients with RPGRIP1-associated Leber congenital amaurosis 6 (LCA6). Methods. After screening 352 unrelated families with clinically diagnosed RP, five LCA6 patients with RPGRIP1 variations from unrelated Chinese families were identified. Full ophthalmology examinations, including decimal best-corrected visual acuity (BCVA), fundus photography, fundus autofluorescence imaging, spectral-domain optical coherence tomography (SD-OCT), full-field electroretinography (ffERG), multifocal electroretinography (mfERG), perimetry, and flash visual evoked potential (FVEP), were performed. Target next-generation sequencing (NGS) and Sanger sequencing were performed for the five patients to identify and to validate candidate disease-causing variants. Results. Five patients were molecularly diagnosed as the LCA6 associated with RPGRIP1 variation, with typical clinical characteristics including congenital night blindness, nystagmus, and visual defect, at an early age. Interestingly, LCA6 exhibited extensive clinical heterogeneity and the changes in the morphology and function were not completely consistent in the five LCA6 patients. Case 1 showed extensive inferior-nasal retinal atrophy with a corresponding area of hypofluorescence in fundus autofluorescence, and the fundus photograph was nearly normal in cases 2 and 3. The ERG results displayed a moderately reduced rod-system response in cases 1 and 2 and a significant reduced rod-system response in case 3. Both case 4 and case 5 showed mottled pigmentation in fundi and an unrecordable rod and cone-system response in ERG. Moreover, we identified eight compound variants and one homozygous variant in the five patients with RPGRIP1. Conclusions. This is the largest report focused on the clinical electrophysiological features of patients with associated LCA6 caused by the variation in the RPGRIP1 gene in the Chinese population with an enriched phenotypic and genotypic background of LCA6 to improve future gene therapies.

Seismic reflection is a proven and effective method commonly used during exploration of deep mineral deposits in Fujian, China. In seismic data processing, rugged depth migration based on wave-equation migration can play a key role in handling surface fluctuations and complex underground structures. Because wave-equation migration in the shot domain cannot output offset-domain common-image gathers in a straightforward way, the use of traditional tools for updating the velocity model and improving image quality can be quite challenging. To overcome this problem, we have used the attribute migration method. This works by sorting the migrated stack results for every single-shot gather into the offset gathers. The value of the offset that corresponds to each image point is obtained from the ratio of the original migration results to the offset-modulated shot-data migration results. A Gaussian function is proposed to map every image point to a certain range of offsets. This helps improve the signal-to-noise ratio, which is especially important in handling low-quality seismic data obtained during mineral exploration. Residual velocity analysis is applied to these gathers to update the velocity model and improve the image quality. The offset-domain common-image gathers are also used directly for real mineral exploration seismic data with rugged depth migration. After several iterations of migration and updating the velocity, our procedure achieves an image quality better than the one obtained with the initial velocity model. The results can help with the interpretation of thrust faults and deep deposit exploration.

Purpose: Leber congenital amaurosis (LCA) is one of the earliest inherited retinal dystrophies (IRD) that leads to blindness. To date, there have been 25 LCA-associated genes reported in China as well as other countries. The current study aimed to present the dominant molecular genetics and clinical features of LCA in the Han population of western China.Methods: Our study comprised 37 patients with strictly defined Leber congenital amaurosis in a cohort of IRD (2009-2019). The mutations were detected by targeted next-generation sequencing (NGS), Sanger sequencing, and segregation analysis. The patients underwent comprehensive clinical examinations, analysis of phenotypes and genotypes.Results: Out of the 37 patients, 34 harbored known LCA genes; the detection rate of mutations was 91.9%. Forty-seven different alleles incorporated 21 novel mutations; 8 were known LCA-associated genes. The three most frequently mutated genes included CRB1 (27.0%), RDH12 (24.3%), and RPGRIP1 (18.9%). The CRB1-associated LCA showed a pigmented fundus; the RDH12-associated LCA featured macular atrophy. Our results revealed that CRB1 and RPGRIP1 genes occupied a greater proportion in the western Chinese population. The proportion of these two genes was similar in other regions of China as well. The difference existed in a larger proportion of RDH12-associated LCA in the western Chinese population.Conclusions: The new findings in our study group polished the spectrum of the novel mutations and phenotypes of LCA with regional and ethnic variations. This comprehensive database can provide essential information for gene therapies.

The slab beneath the Alboran Sea is a consequence of the collision between two continents (Europe and Africa), which was initiated along the northeastern Spanish coast, experienced slab rollback and migrated to the area adjacent to the two continents. The tectonic background in this area includes episodes of collisions with adjacent continents as well as extension of those basins in the western Mediterranean. Here, we present three-dimensional (3D) Kirchhoff-approximate generalized Radon transform (GRT) images to further constrain the lithospheric structures previously identified by other researchers. The GRT images were calculated from the same P-to-S (Pds or Ps) teleseismic receiver functions (RFs) as the previous common conversion point (CCP) stacking, but the GRT data provide figures with greater resolution than the Pds RFs CCP results. This study indicates that the Alboran Slab may have completely detached from the crustal base under the western Betics Mountains and that a larger range of lithospheric ‘peeling off’ developed beneath the western part of the Betics Mountains than some previous results have claimed. The observed thin lithosphere under the Middle Atlas (MA) and eastern High Atlas (HA) may have a geodynamic relationship with lithospheric delamination under the eastern part of the Rif Mountains, which has also led to the thin lithosphere under the eastern Rif. According to the thick lithosphere under the western HA, the shallow LAB under the MA and eastern HA may have no heat-flow connection with the Canary mantle plume, as stated in several previous studies.

Objective The current methods used to assess visual function in blind retinitis pigmentosa (RP) patients are mostly subjective. We aimed to identify effective, objective methods. Methods We enrolled patients diagnosed with blindness associated with RP; we finally selected 26 patients (51 eyes) with a visual field radius less than 10 degrees and divided them into the following 4 groups by best-corrected visual acuity (BCVA): group 1, no light perception (NLP, 4 eyes); group 2, light perception (LP, 12 eyes); group 3, hand movement or finger counting (faint form perception, FFP, 22 eyes); and group 4, BCVA from 0.1 to 0.8 (form perception, FP, 13 eyes). All patients underwent optometry, optical coherence tomography (OCT), color fundus photography, fundus autofluorescence (FAF), full field electroretinography (ffERG), pattern electroretinography (PERG), multifocal electroretinography (mf-ERG), pattern visual evoked potential (PVEP), flash visual evoked potential (FVEP), and pupillary light response (PLR) assessments. Five patients in groups 1, 2, and 3 (1, 2, and 2 subjects, respectively) underwent functional magnetic resonance imaging (fMRI) scans and were compared with five healthy subjects. Results The outer plexiform layer was thinner in group 1, and the outer nuclear layer was thinner in groups 1 and 2. The ffERG, PERG, and mf-ERG findings were unrecordable in all four groups. The P2 amplitude of the FVEP was significantly lower in groups 1 and 2, while the P100 amplitude of the PVEP was higher in groups 2, 3 and 4 than in group 1. After white- and blue-light stimuli, the PLR thresholds in the patients without form perception were significantly higher. The threshold of the PLR stimulated by blue and white light was negatively correlated with the amplitudes of P2 and P100. Moreover, the fMRI findings showed that some RP patients have significant visual cortex activation in response to certain types of stimulation. However, statistical analysis was not performed because of the small number of cases. Conclusions OCT, VEP, PLR and fMRI assessments can evaluate residual visual pathway function in blind RP patients. Significance Our study may have clinical significance for the potential prediction of RP patient prognoses and the effects after clinical trials.

Edge detection is one of the most commonly used methods for the interpretation of potential field data, because it can highlight the horizontal inhomogeneous of underground geological bodies (faults, tectonic boundaries, etc.). A variety of edge detection methods have been reported in the literature, most of which are based on the combined transformation results of horizontal and vertical derivatives of the observations. Consequently, these edge detection methods are sensitive to noise. Therefore, noise reduction is desirable ahead of applying edge detection methods. However, the application of conventional filters smears discontinuities in the data to a certain extent, which would inevitably induce unfavourable influence on subsequent edge detection. To solve this problem, a novel edge-preserving smooth method for potential field data is proposed, which is based on the concept of guided filter developed for image processing. The new method substitutes each data point by a combination of a series of coefficients of linear functions. It was tested on synthetic model and real data, and the results showed that it can effectively smooth potential field data while preserving major structural and stratigraphic discontinuities. The obtained data from the new filter contain more obvious features of existing faults, which brings advantageous to further geological interpretations.

Purpose: To characterize and monitor the clinical and electrophysiological features of a Chinese patient with KCNV2 retinopathy.Methods: A 17-year-old Chinese male with the diagnosis of cone dystro...

Purpose：To evaluate the effectiveness after implementing the PROSTATE care model which aims to prepare and support patients for radical prostatectomy. Methods: The PROSTATE care model was raised and developed based on literature review and available clinical practice guidelines. A total of 673 patients with prostate cancer were enrolled, including 295 patients who received conventional nursing pathway after radical prostatectomy between January 2015 and December 2017, and 378 patients after initiation of PROSTATE care model between January 2018 and December 2020. Length of hospital stay, postoperative outcomes, continence of patients, patient satisfaction and other related patient outcomes were compared between the two groups.Results: After implementation, the average length of stay decreased from 9.19±1.03 to 7.64±0.98 days (pConclusion: The PROSTATE care model is focused on the patient-orientated care with efforts from multi-disciplinary team. This model ensures the perioperative safety, promotes faster recovery and improves quality of life without increasing complication rates.

The Southwestern area of Fujian Province in China contains a major metallogenic belt. There have been three major tectonic movements since the Late Paleozoic, and the thrusts here are the main mineral deposits. These occurred between the Early Carboniferous and Late Permian eras. Due to dramatic undulations in the surface and associated complex underground structures, a single geophysical method cannot provide reliable imaging results. This is largely due to difficulties in data acquisition and processing. Seismic exploration provides one example. Using this method, raw shot gathers have a low signal-to-noise ratio because of the undulations in the topography. Furthermore, strong lateral velocity variation makes the migration process exceedingly difficult. This means that interpretations of the resulting reflection seismic profile give rise to uncertainty. For this reason, two-dimensional reflection seismology and controlled source audio-frequency magnetotellurics (CSAMT) electromagnetic sounding techniques were performed. After initially completing conventional processing on the seismic reflection data, subsequent pre-stack depth migration (PSDM) over the rugged topography yielded a much better image. It was able to identify thrust faults and magma intrusions. Then, using CSAMT, inversion was conducted with the same topography as the seismic reflection. By combining the migrated seismic profile, inverted resistivity profile, and borehole data, a vertical geological model was constructed. This proved the existence of an overlapped thrust, and it also indicated the possible presence of deeper mineralization.

Retinitis pigmentosa (RP) is a hereditary retinal degeneration disease with no effective therapeutic approaches. Inflammatory and immune disorders are thought to play an important role in the pathogenesis of RP. Human umbilical cord mesenchymal stem cells (UCMSCs), with multiple biological functions such as anti-inflammation and immunoregulation, have been applied in different systemic diseases. We conducted a phase I/II clinical trial aiming to evaluate the safety and efficacy of intravenous administration of UCMSCs in advanced RP patients. All 32 subjects were intravenously infused with one dose of 10

Bietti’s crystalline dystrophy (BCD) is an incurable retinal disorder caused by the polypeptide 2 of cytochrome P450 family 4 subfamily V (CYP4V2) mutations. Patients with BCD present degeneration of retinal pigmented epithelial (RPE) cells and consequent blindness. The lack of appropriate disease models and patients’ RPE cells limits our understanding of the pathological mechanism of RPE degeneration. In this study, using CYP4V2 mutant pluripotent stem cells as disease models, we demonstrated that RPE cells with CYP4V2 mutations presented a disrupted fatty acid homeostasis, which were characterized with excessive accumulation of poly-unsaturated fatty acid (PUFA), including arachidonic acid (AA) and eicosapentaenoic acid (EPA). The PUFA overload increased mitochondrial reactive oxygen species, impaired mitochondrial respiratory functions, and triggered mitochondrial stress-activated p53-independent apoptosis in CYP4V2 mutant RPE cells. Restoration of the mutant CYP4V2 using adeno-associated virus 2 (AAV2) can effectively reduce PUFA deposition, alleviate mitochondria oxidative stresses, and rescue RPE cell death in BCD RPE cells. Taken together, our results highlight a role of PUFA-induced mitochondrial damage as a central node to potentiate RPE degeneration in BCD patients. AAV2-mediated gene therapy may represent a feasible strategy for the treatment of BCD., Graphical Abstract, This study is designed to understand mechanisms of retinal degeneration in patients with Bietti’s crystalline dystrophy (BCD) by using pluripotent stem cells and genomic editing approaches. It revealed that excessive poly-unsaturated fatty acid (PUFA) is the key to damaging retinal mitochondrial functions. Application of gene therapy can effectively alleviate BCD.

Mucopolysaccharidosis type IIIC (MPSIIIC; MIM#252930) is a rare autosomal recessive lysosomal storage disease caused by variations in the heparan-α-glucosaminide N-acetyltransferase (HGSNAT; MIM#61...

The axial constraint is an important constraint for the inversion of gravity data with which the dip information of the target geological bodies can be incorporated effectively. However, poor selection of the dip angles would inevitably lead to unreasonable inversion results. To reduce the errors caused by inappropriate angle estimation, this study proposes a new variable angle axial constraint for the inversion of gravity data. Moreover, to extend the utility of this new constraint, a method for employing multi-axial constraint is also introduced. The presented novel multi-axial constraint with a variable angle can be used to solve the inverse problems for complex geological bodies. We present a detailed iterative algorithm to solve the inverse problems with the presented constraints, in which the randomized singular value decomposition (RSVD) is used to solve the total objective function, and the generalized cross-validation (GCV) is utilized to estimate the regularization parameter. Numerous tests on synthetic gravity data with noise demonstrate that the inversion errors induced by inappropriate angle estimation can be greatly reduced by using the new constraints. Moreover, the presented methodology is successfully applied to a field data from the Morro do Engenho complex in the center of Brazil. This application also demonstrates the effectiveness of the proposed constraint.

Objectives To evaluate the long‐term biosafety and efficacy of transplantation of human embryonic stem cells‐derived retinal pigment epithelial (hESC‐RPE) cells in early‐stage of Stargardt macular degeneration (STGD1). Materials and methods Seven patients participated in this prospective clinical study, where they underwent a single subretinal transplantation of 1 × 105 hESC‐RPE cells in one eye, whereas the fellow eye served as control. These patients were reassessed for a 60‐month follow‐up through systemic and ophthalmic examinations. Results None of the patients experienced adverse reactions systemically or locally, except for two who had transiently high intraocular pressure post‐operation. Functional assessments demonstrated that all of the seven operated eyes had transiently increased or stable visual function 1‐4 months after transplantation. At the last follow‐up visit, two of the seven eyes showed visual function loss than the baseline; however, one of them showed a stable visual acuity when compared with the change of fellow eye. Obvious small high reflective foci in the RPE layer were displayed after the transplantation, and maintained until the last visit. Interestingly, three categories of patients who were classified based on autofluorescence, exhibited distinctive patterns of morphological and functional change. Conclusions Subretinal transplantation of hESC‐RPE in early‐stage STGD1 is safe and tolerated in the long term. Further investigation is needed for choosing proper subjects according to the multi‐model image and function assessments., Transplantation of human embryonic stem cells‐derived retinal pigment epithelial (hESC‐RPE) cells in the patients with early stage of STGD1 is safe and tolerated in the long term. Objective visual functions test after transplantation were mostly remained as the preoperative levels or improved transiently in some cases. Morphology test showed pigmentation in the fundus and high reflective foci in the RPE layer by OCT. Moreover, a new fundus autofluorescence classification was applied to group the subjects for stem cell transplantation and monitored the clinical outcomes.

The inversion of potential field data has widely utilized the generalized cross-validation (GCV) and the unbiased predictive risk estimator (UPRE) methods to determine the regularization parameter. However, these two methods are time-consuming and it is difficult for them to determine the optimal linear search range including the optimal regularization. To solve these problems, this article improves the GCV and UPRE methods using the RGSVD (randomized generalized singular value decomposition) algorithm. The improved methods first use the randomized algorithm to compute an approximate generalized singular value decomposition (GSVD) with less computational time. Then, the optimal linear search range is determined based on the generalized singular values. Finally, the GCV and the UPRE functions are efficiently computed on the basis of the results from the RGSVD algorithm. In this way, the GCV and UPRE methods using the RGSVD algorithm are able to determine the optimal regularization parameter fast and effectively. One comparative test shows the effectiveness and efficiency of the GCV and the UPRE methods using the RGSVD algorithm.

Seismic reflection data used in mineral exploration are usually of poor quality because of rough topography and small-scale heterogeneities. However, there is an increasing demand for accurate imaging processes that can obtain such data. Here, we have developed a practical rugged depth migration method based on the finite-difference one-way wave equation. It can be used to improve imaging quality when faced with rough topography and complex geologic features. First, synthetic data are used to illustrate the errors and problems that cause unsatisfactory imaging results. This is usually because no consideration is given to rough topography during conventional processing procedures. To address this, a depth migration method that begins with the rugged topography is introduced. It can be used to produce better images. Real data from mineral exploration activities in Fujian, China, are then used to demonstrate the practical use of this method. We also compare two computational processes: The first corrects the data back to the original surface and then builds a velocity model before conducting rugged depth migration; the second process involves performing rugged depth migration on processed data featuring a smoothed surface following short-wavelength static correction and residual correction. The imaging results indicate that the section obtained from the processed data has better quality. They also indicate that the imaging quality of the original surface is affected by the built velocity model, which cannot include near-surface and small-scale structures.

In the literature, there are numerous derivative-based transforms for gravity and magnetic data sets, with which relevant features can be highlighted. However, almost all of them face the problem of instability in derivative calculation. Therefore, before applying derivative-based transforms, noise reduction is often applied to improve the quality of the data. Nevertheless, the application of conventional filters typically blurs horizontal gradients in the data, which can adversely affect subsequent transforms, for example, the sharp boundaries of the causative bodies may be obscured. To handle the above issue, this study is the first to employ the bilateral filter, used in digital image processing, for improving the derivative-based transforms for gravity and magnetic data sets. The filter replaces each data point by a weighted average of its neighbors. The established weights take into account both the geometric and amplitude closeness between the data points used. Synthetic tests indicate that the proposed method can effectively filter potential field data without distorting the structural features greatly. Thus, the performance of subsequent derivative-based transforms can be improved. The new method was applied to the magnetic data collected over the Dapai polymetallic deposit in Fujian Province, South China. This real example shows that the results obtained from the proposed method contain more pronounced features of existing faults and thus contributes to further geological interpretation.

Reverse time migration (RTM) is an indispensable but computationally intensive seismic exploration technique. Graphics processing units (GPUs) by NVIDIA® offer the option for parallel computations and speed improvements in such high-density processes. With increasing seismic imaging space, the problems associated with multi-GPU techniques need to be addressed. We propose an efficient scheme for multi-GPU programming based on the features of the compute-unified device Architecture (CUDA) using GPU hardware, including concurrent kernel execution, CUDA streams, and peer-to-peer (P2P) communication between the different GPUs. In addition, by adjusting the computing time for imaging during RTM, the data communication times between GPUs become negligible. This means that the overall computation efficiency improves linearly, as the number of GPUs increases. We introduce the multi-GPU scheme by using the acoustic wave propagation and then describe the implementation of RTM in tilted transversely isotropic (TTI) media. Next, we compare the multi-GPU and the unified memory schemes. The results suggest that the proposed multi-GPU scheme is superior and, with increasing number of GPUs, the computational efficiency improves linearly.