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Groundwater withdrawal can cause localized and rapid poroelastic subsidence, spatially broad elastic uplift of low amplitude, and changes in the gravity field. Constraining groundwater loss in Mexico City, we analyze data from the Gravity Recovery and Climate Experiment and its follow-on mission (GRACE/FO) and Synthetic Aperture Radar (SAR) Sentinel-1A/B images between 2014 and 2021. GRACE/FO observations yield a groundwater loss of 0.85-3.87 km(3)/yr for a region of similar to 300 x 600 km surrounding Mexico City. Using the high-resolution interferometric SAR data set, we measure >35 cm/yr subsidence within the city and up to 2 cm/yr of uplift in nearby areas. Attributing the long-term subsidence to poroelastic aquifer compaction and the long-term uplift to elastic unloading, we apply respective models informed by local geology, yielding groundwater loss of 0.86-12.57 km(3)/yr. Our results suggest Mexico City aquifers have been depleting at faster rates since 2015, exacerbating the socioeconomic and health impacts of long-term groundwater overdrafts.

The sliding mode observer is a useful method for estimating the system state and the unknown disturbance. However, the traditional single-layer observer might still suffer from high pulse when the output measurement is mixed with noise. To improve the estimation quality, a new cascade sliding mode observer containing multiple discontinuous functions is proposed in this letter. The proposed observer consists of two layers: the first layer is a traditional sliding mode observer, and the second layer is a cascade observer. The measurement noise issue is considered in the source system model. An alternative method how to design the observer gains of the two layers, together with how to examine the effectiveness of the compensator based closed-loop system, are offered. A numerical example is provided to demonstrate the effectiveness of the proposed method. The observation structure proposed in this letter not only smooths the estimated state but also reduces the control consumption.

Industrial activity away from plate boundaries can induce earthquakes and has evolved into a global issue. Much of the induced seismicity in the United States' midcontinent is attributed to a direct pressure increase from deep wastewater disposal. This mechanism is not applicable where deep basement faults are hydraulically isolated from shallow injection aquifers, leading to a debate about the mechanisms for induced seismicity. Here, we compile industrial, seismic, geodetic, and geological data within the Delaware Basin, western Texas, and calculate stress and pressure changes at seismogenic depth using a coupled poroelastic model. We show that the widespread deep seismicity is mainly driven by shallow wastewater injection through the transmission of poroelastic stresses assuming that unfractured shales are hydraulic barriers over decadal time scales. A zone of seismic quiescence to the north, where injection-induced stress changes would promote seismicity, suggests a regional tectonic control on the occurrence of induced earthquakes. Comparing the poroelastic responses from injection and extraction operations, we find that the basement stress is most sensitive to shallow reservoir hydrogeological parameters, particularly hydraulic diffusivity. These results demonstrate that intraplate seismicity can be caused by shallow human activities that poroelastically perturb stresses at hydraulically isolated seismogenic depths, with impacts on seismicity that are preconditioned by regional tectonics.

Induced seismicity linked to geothermal resource exploitation, hydraulic fracturing, and wastewater disposal is evolving into a global issue because of the increasing energy demand. Moderate to large induced earthquakes, causing widespread hazards, are often related to fluid injection into deep permeable formations that are hydraulically connected to the underlying crystalline basement. Using injection data combined with a physics-based linear poroelastic model and rate-and-state friction law, we compute the changes in crustal stress and seismicity rate in Oklahoma. This model can be used to assess earthquake potential on specific fault segments. The regional magnitude-time distribution of the observed magnitude (M) 3+ earthquakes during 2008-2017 is reproducible and is the same for the 2 optimal, conjugate fault orientations suggested for Oklahoma. At the regional scale, the timing of predicted seismicity rate, as opposed to its pattern and amplitude, is insensitive to hydrogeological and nucleation parameters in Oklahoma. Poroelastic stress changes alone have a small effect on the seismic hazard. However, their addition to pore-pressure changes can increase the seismicity rate by 6-fold and 2-fold for central and western Oklahoma, respectively. The injection-rate reduction in 2016 mitigates the exceedance probability of M5.0 by 22% in western Oklahoma, while that of central Oklahoma remains unchanged. A hypothetical injection shut-in in April 2017 causes the earthquake probability to approach its background level by ∼2025. We conclude that stress perturbation on prestressed faults due to pore-pressure diffusion, enhanced by poroelastic effects, is the primary driver of the induced earthquakes in Oklahoma.

Induced seismicity linked to geothermal resource exploitation, hydraulic fracturing, and wastewater disposal is evolving into a global issue because of the increasing energy demand. Moderate to large induced earthquakes, causing widespread hazards, are often related to fluid injection into deep permeable formations that are hydraulically connected to the underlying crystalline basement. Using injection data combined with a physics-based linear poroelastic model and rate-and-state friction law, we compute the changes in crustal stress and seismicity rate in Oklahoma. This model can be used to assess earthquake potential on specific fault segments. The regional magnitude-time distribution of the observed magnitude (M) 3+ earthquakes during 2008-2017 is reproducible and is the same for the 2 optimal, conjugate fault orientations suggested for Oklahoma. At the regional scale, the timing of predicted seismicity rate, as opposed to its pattern and amplitude, is insensitive to hydrogeological and nucleation parameters in Oklahoma. Poroelastic stress changes alone have a small effect on the seismic hazard. However, their addition to pore-pressure changes can increase the seismicity rate by 6-fold and 2-fold for central and western Oklahoma, respectively. The injection-rate reduction in 2016 mitigates the exceedance probability of M5.0 by 22% in western Oklahoma, while that of central Oklahoma remains unchanged. A hypothetical injection shut-in in April 2017 causes the earthquake probability to approach its background level by ∼2025. We conclude that stress perturbation on prestressed faults due to pore-pressure diffusion, enhanced by poroelastic effects, is the primary driver of the induced earthquakes in Oklahoma.

Climate extremes threaten global food security, and compound events, such as late spring heavy and warmer rainfall over snow and subsequent flooding, exacerbate this vulnerability. Despite frequent occurrences in recent years, a quantitative understanding of the compound weather events' impacts remains elusive. Here, we use Synthetic Aperture Radar data from Sentinel-1 and normalized difference vegetation index data from MODIS satellites to map the spring 2019 U.S. Midwest flood extent and evaluate its impact on crop loss. We find a statistically significant association between flooded counties and those with plant greenup delay, while the correlation between flood area percent and amount of green-up delay remains weak, albeit reliable. An analysis of the stream gage time series and crop loss records shows that during the past ∼70 years, ∼43% of spring large discharges are associated with widespread crop loss. We also find an increase in streams' discharge frequency and magnitude across the Midwest, indicating the possibility of a future increase in crop loss due to spring flooding. This study highlights the importance of Earth-observing satellite data for developing climate adaptation and resilience plans.

The M5 Mentone earthquake that occurred on March 26, 2020, was the largest event recorded over the last 2 decades in West Texas within the Delaware Basin, a U.S. major petroleum-producing area. Also, numerous hydrofracturing and wastewater disposal wells are spread across this region. Within a 30 km distance to mainshock, eight class-II injection wells for industrial wastewater disposal target the deep porous Ellenburger aquifer at an average rate of 1.36 x 10(6) barrel (BBL) per month during 2012-2020. Poroelastic models of fluid diffusion show these nearby injectors collectively imparted up to 80.5 kPa of Coulomb stress at the mainshock location, capable of triggering this M5 event. Assuming the Mentone event occurs when pore-pressure increase is maximum, the time delay between peak injection and the M5 occurrence corresponds with an optimal permeability of 6.76 x 10(-14) m(2) for the Ellenburger aquifer layer, in agreement with independent estimates.

The M5 Mentone earthquake that occurred on March 26, 2020, was the largest event recorded over the last 2 decades in West Texas within the Delaware Basin, a U.S. major petroleum-producing area. Also, numerous hydrofracturing and wastewater disposal wells are spread across this region. Within a 30 km distance to mainshock, eight class-II injection wells for industrial wastewater disposal target the deep porous Ellenburger aquifer at an average rate of 1.36 x 10(6) barrel (BBL) per month during 2012-2020. Poroelastic models of fluid diffusion show these nearby injectors collectively imparted up to 80.5 kPa of Coulomb stress at the mainshock location, capable of triggering this M5 event. Assuming the Mentone event occurs when pore-pressure increase is maximum, the time delay between peak injection and the M5 occurrence corresponds with an optimal permeability of 6.76 x 10(-14) m(2) for the Ellenburger aquifer layer, in agreement with independent estimates.

Climate extremes threaten global food security, and compound events, such as late spring heavy and warmer rainfall over snow and subsequent flooding, exacerbate this vulnerability. Despite frequent occurrences in recent years, a quantitative understanding of the compound weather events' impacts remains elusive. Here, we use Synthetic Aperture Radar data from Sentinel-1 and normalized difference vegetation index data from MODIS satellites to map the spring 2019 U.S. Midwest flood extent and evaluate its impact on crop loss. We find a statistically significant association between flooded counties and those with plant greenup delay, while the correlation between flood area percent and amount of green-up delay remains weak, albeit reliable. An analysis of the stream gage time series and crop loss records shows that during the past ∼70 years, ∼43% of spring large discharges are associated with widespread crop loss. We also find an increase in streams' discharge frequency and magnitude across the Midwest, indicating the possibility of a future increase in crop loss due to spring flooding. This study highlights the importance of Earth-observing satellite data for developing climate adaptation and resilience plans.

This paper discusses the noisy phase retrieval problem: recovering a complex image signal with independent noise from quadratic measurements. Inspired by the dark fringes shown in the measured images of the array detector, a novel phase retrieval approach is proposed and demonstrated both theoretically and experimentally to recognize the dark fringes and bypass the invalid fringes. A more accurate relative phase ratio between arbitrary two pixels is achieved by calculating the multiplicative ratios (or the sum of phase difference) on the path between them. Then the object phase image can be reconstructed precisely. Our approach is a good choice for retrieving high-quality phase images from noisy signals and has many potential applications in the fields such as X-ray crystallography, diffractive imaging, and so on., Comment: 14 pages, 5 figures

Objective: To evaluate the efficacy and safety of rifapentine(RPT) and rifampicin(RFP) in treatment of pulmonary tuberculosis with Meta-analysis, and provide a reliable and scientific evidence of evidence-based medicine for clinical application of RPT in tuberculosis treatment. Methods: The articles related to the efficacy and safety of RPT and RFP in the treatment of pulmonary tuberculosis, and randomized clinical controlled trials (RCT) or clinical controlled trials (CCT) published in the openly journals either in Chinese or English from 1999 to July 2010 were searched by computer. The databases were as follows: Ovid-medline, CBMdisc, Pubmed, CNKI, Wanfang database and Weipu database. Some pulmonary tuberculosis journals which didn't publish on line had also been searched by hand. Results: There were 18 RCTs and 6 CCTs were finally selected. In the aspect of efficacy, the 2-month sputum negative conversion rate of the primary treated tuberculosis cases, the obvious effective rate and curable rate of cavity at the end of treatment period of relapse tuberculosis and recurrence rate of tuberculosis in the following 2 or 3 years after treatment period of the relapse tuberculosis cases were all significantly different between RPT and RFP groups, respectively (P<0.05). RPT was more effective than RFP . There were no significant differences between two groups on other indexes, such as 2-month sputum negative conversion rate of the relapse tuberculosis cases, and sputum negative conversion rates both of the primary and relapse tuberculosis cases at the end of treatment period of tuberculosis, and obvious effective rate and curable rate of cavity at the end of the treatment period of the primary treated tuberculosis cases(P>0.05). As for the evaluation of safety, the combined analysis results showed that skin rash and drug fever showed no significant differences(P>0.05) , other indexes all showed significant differences between two groups (P<0.05), such as total drug side

Objective: To evaluate the efficacy and safety of rifapentine(RPT) and rifampicin(RFP) in treatment of pulmonary tuberculosis with Meta-analysis, and provide a reliable and scientific evidence of evidence-based medicine for clinical application of RPT in tuberculosis treatment. Methods: The articles related to the efficacy and safety of RPT and RFP in the treatment of pulmonary tuberculosis, and randomized clinical controlled trials (RCT) or clinical controlled trials (CCT) published in the openly journals either in Chinese or English from 1999 to July 2010 were searched by computer. The databases were as follows: Ovid-medline, CBMdisc, Pubmed, CNKI, Wanfang database and Weipu database. Some pulmonary tuberculosis journals which didn't publish on line had also been searched by hand. Results: There were 18 RCTs and 6 CCTs were finally selected. In the aspect of efficacy, the 2-month sputum negative conversion rate of the primary treated tuberculosis cases, the obvious effective rate and curable rate of cavity at the end of treatment period of relapse tuberculosis and recurrence rate of tuberculosis in the following 2 or 3 years after treatment period of the relapse tuberculosis cases were all significantly different between RPT and RFP groups, respectively (P<0.05). RPT was more effective than RFP . There were no significant differences between two groups on other indexes, such as 2-month sputum negative conversion rate of the relapse tuberculosis cases, and sputum negative conversion rates both of the primary and relapse tuberculosis cases at the end of treatment period of tuberculosis, and obvious effective rate and curable rate of cavity at the end of the treatment period of the primary treated tuberculosis cases(P>0.05). As for the evaluation of safety, the combined analysis results showed that skin rash and drug fever showed no significant differences(P>0.05) , other indexes all showed significant differences between two groups (P<0.05), such as total drug side

Objective: To evaluate the efficacy and safety of rifapentine(RPT) and rifampicin(RFP) in treatment of pulmonary tuberculosis with Meta-analysis, and provide a reliable and scientific evidence of evidence-based medicine for clinical application of RPT in tuberculosis treatment. Methods: The articles related to the efficacy and safety of RPT and RFP in the treatment of pulmonary tuberculosis, and randomized clinical controlled trials (RCT) or clinical controlled trials (CCT) published in the openly journals either in Chinese or English from 1999 to July 2010 were searched by computer. The databases were as follows: Ovid-medline, CBMdisc, Pubmed, CNKI, Wanfang database and Weipu database. Some pulmonary tuberculosis journals which didn't publish on line had also been searched by hand. Results: There were 18 RCTs and 6 CCTs were finally selected. In the aspect of efficacy, the 2-month sputum negative conversion rate of the primary treated tuberculosis cases, the obvious effective rate and curable rate of cavity at the end of treatment period of relapse tuberculosis and recurrence rate of tuberculosis in the following 2 or 3 years after treatment period of the relapse tuberculosis cases were all significantly different between RPT and RFP groups, respectively (P<0.05). RPT was more effective than RFP . There were no significant differences between two groups on other indexes, such as 2-month sputum negative conversion rate of the relapse tuberculosis cases, and sputum negative conversion rates both of the primary and relapse tuberculosis cases at the end of treatment period of tuberculosis, and obvious effective rate and curable rate of cavity at the end of the treatment period of the primary treated tuberculosis cases(P>0.05). As for the evaluation of safety, the combined analysis results showed that skin rash and drug fever showed no significant differences(P>0.05) , other indexes all showed significant differences between two groups (P<0.05), such as total drug side