•SLV aquifer deforms seasonally with ∼50-mm vertical and ∼30-mm horizontal amplitude.•Seasonal water storage cycles of the target aquifer are 0.03-0.06-km3.•Phase shifts across active faults exist in ...both water level and deformation.•Seasonal stress changes from volume strain are ∼100 times larger than from water load.•Insignificant annual periodicity of SLV seismicity.
Aquifers and fault zones may interact through groundwater flow and stress redistribution, yet their spatiotemporal relationship remains enigmatic. Here we quantify changes in water storage and associated stress along the Wasatch Fault Zone in Salt Lake Valley, recently shaken by a M5.7 earthquake on March 18th, 2020. Ground deformation mapped by Sentinel-1 SAR imagery (2014-2019) reveals an elongated area with ∼50-mm seasonal uplift corresponding to 0.03-0.06-km3 water storage cycles. Phase shifts across active faults in both water level and deformation suggest control by the low-permeability structures. The seasonal stress changes on the adjoining faults from poroelastic volume strain are two orders of magnitude larger than those from hydrological surface loading, but both are small compared to the annual increase of tectonic loading at seismogenic depths. Historic seismic events, limited in number, do not exhibit statistically significant annual periodicity and hydrological modulation of microseismicity or triggering of the recent M5.7 event is not evident.
Due to the advantages of high measurement accuracy and good robustness, structured light vision (SLV) methods have been extensively applied for 3-D reconstruction in air and water scene. However, ...most current SLV systems cannot adapt to different media without recalibration, and have the disadvantages of complicated calibration process including SLV model parameter calibration in air and water. In order to overcome these problems, a SLV 3-D reconstruction system for different media considering refraction is proposed. First, an accurate SLV measurement model is established for 3-D reconstruction in different media, which considers structured light plane refraction model and camera refraction model simultaneously. Specifically, the relationship of the SLV model parameters in air and water are proposed. Second, a simple and efficient calibration method of SLV model parameters is presented. After SLV model calibration in air and refraction interface parameters calibration, the SLV model parameters in different media can be obtained accurately without recalibration. Finally, a compact SLV system is developed, and calibration experiments and 3-D reconstruction experiments in air and different turbid water are conducted. Experiment results show that the proposed system could obtain satisfactory 3-D reconstruction performance in air and different turbidity water.
Dynamically measuring rail profile using the structured-light vision suffers from random vibrations on the line laser projector, which would cause distorted rail profiles. This paper presents a ...simple and effective distortion rectifying method to address this issue. The distorted rail profile is rectified by easily projecting it onto an auxiliary plane which is parallel to the cross section of rail. In order to establish the auxiliary plane, three profiles formed by radiating multiline structured light on rail are used to fit the rail longitudinal axis. More importantly, only one of the light planes is required to be calibrated beforehand. The others are calibrated online with the proposed self-calibration method, which is based on collinearity and parallelity constraints on the scene points of different rail profiles and requires only one image of the scene. Apart from evaluating the implementation with comprehensive experiments, we compare our method against other published works. The results exhibit its effectiveness and superiority in terms of the dynamic measurement of the rail profile.
We sought to evaluate contractile function in single-ventricle patients before and after imposition of Fontan physiology.
Single right ventricle (SRV; n = 38) and single left ventricle (SLV; n = 11) ...patients underwent cardiac magnetic resonance imaging pre and post Fontan operation. Global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain were measured along with ejection fraction (EF) and atrioventricular valve regurgitation (AVVR).
Age at cardiac magnetic resonance imaging before the Fontan operation was 3.1 ± 1.3 years and after the Fontan procedure was 5.8 ± 2.7 years. There were no significant EF differences between SRV and SLV patients before and after the Fontan procedure, and EF did not deteriorate significantly after the Fontan operation. GRS was significantly lower for SRV patients than for SLV patients before (24.3% vs 32.1%; P = .048) and after (21.8% vs 29.7%; P = .045) the Fontan procedure. GRS and GCS of the SRV patients deteriorated significantly after the Fontan operation (GRS, P = .01; GCS, P = .009). Strains showed positive correlations before and after the Fontan operation with positive correlations among each strain. Within all patients, strains correlated positively with EF. Strains and EF negatively correlated with AVVR (GRS P = .03, r = −0.22; GCS P = .03, r = −0.23; EF P < .001, r = −0.37).
Strains were lower for SRV than for SLV patients before and after the Fontan operation and deteriorated after the Fontan operation. Our study suggests that strain measures might detect ventricular deterioration earlier than EF. Because strains before and after the Fontan operation were positively correlated, and negatively correlated with AVVR, the early institution of myocardial protective therapy including AVVR management, especially for SRV patients, might have benefit.
The present study described a combining thermotherapy with meristem culture for improved eradication of onion yellow dwarf virus (OYDV) and shallot latent virus (SLV) from co‐infected in ...vitro‐cultured shallot shoots. In vitro‐cultured shoots infected with OYDV and SLV were thermo‐treated at a constant temperature of 36°C for 0, 2 and 4 weeks, and then meristems (0.5 mm) containing 1–2 leaf primordia were excised and cultured for shoot regrowth. Meristem culture without thermotherapy produced much higher levels of survival (100%) and shoot regrowth (55%) than those (62% survival and 32% shoot regrowth) produced by the procedure combining 4 weeks of thermotherapy with meristem culture. However, much higher virus‐free frequencies (70% for OYSV, 80% for SLV and 50% for both viruses) were obtained in the latter than those (10% for OYSV, 15% for SLV and 10% for both viruses) obtained in the former. Histological and subcellular studies showed that thermotherapy imposed stress or damage to the cells of meristems, thus resulting in reduced meristem survival and shoot regrowth. Studies on virus location revealed considerable alternations of virus distribution patterns in the thermo‐treated meristems. The results of histological and subcellular studies and analysis of virus distribution pattern added valuable experimental data in the combining thermotherapy with meristem culture for virus eradication. These data provided explanations as to why combining thermotherapy with meristem culture improved the eradication of OYDV and SLV from the virus‐infected in vitro shallot shoots.
Potato onion (Allium cepa L. var. aggregatum Don) is an important cash crop in northeastern China. It has the characteristics of cold tolerance and high yield and is very popular among consumers in ...this region. However, shallot latent virus (SLV) and onion yellow dwarf virus (OYDV) reduce the height and yield of potato onion plants. The detection of viruses on potato onion plants and virus elimination of plants are the primary ways to prevent viral infection and spread. We used duplex reverse‐transcription polymerase chain reaction (RT‐PCR) and in situ hybridization to detect SLV and OYDV viruses, and determined that the tissue with the least virus content was the apical meristem. Cultivation of detoxifying plants was by multi‐generation shoot tips. The results showed that duplex RT‐PCR could detect SLV and OYDV in potato onion. By use of multi‐generation shoot tip virus elimination, we have demonstrated that multiple generations of shoot tip virus elimination can produce non‐toxic plants during the third generation of virus elimination, and the elimination rate of virus was 96.2%. This work provides a more convenient method for potato onion virus detection and improves the detection efficiency. This method will in turn aid in the development of virus elimination and rapid propagation methods for potato onion.
Increased production of potato onions using shoot tip virus elimination.
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