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Cavity formations by soil dissolution or underground collapses are at the origin of large surface subsidence that constitutes a risk of damage or failure for infrastructures. Soil reinforcement with geosynthetics positioned at shallow depth is an economical and functional solution to reduce the induced surface settlements. Previous research has mainly focused on the load transfer mechanism and the arching effect in cohesionless reinforced backfills when the cavity opens. Experimental and numerical studies dealing with cohesive soils are very rare, although this situation is commonly found in practice. To overcome this lack of knowledge, a numerical study based on Discrete Element Modelling is carried out to better understand the load transfer mechanisms that are mobilized in cohesive embankments prone to underground cavity opening. The results are compared with experimental data obtained on a small-scale laboratory model in terms of vertical and horizontal displacements of both soil and geosynthetics. The numerical results focus on the collapse mechanisms of the cohesive embankment, the load transfer mechanisms, the shape of the vertical load distribution acting on the geosynthetic layer, the strain and traction forces within the geosynthetic sheet. • A numerical DEM model is proposed to analyse the load transfer in geosynthetic reinforced cohesive soil at the failure • The experiments and the numerical results exhibit a backfill failure mechanism as a rigid trapezoidal-shaped block of soil • Displacements and strains of the membrane show a frictional and sliding mechanism of the anchorage areas near the cavity • The membrane shows a flatness in the central part of the cavity due to the presence of the collapsed rigid block onto it. All the mechanisms are different from those observed e case of a geosynthetic reinforced granular soil addressed in the literature [ABSTRACT FROM AUTHOR]

Anterior cervical corpectomy and fusion achieves foraminal radicular and central medullary decompression and spinal stabilization in staged lesions. Many bone graft materials have been developed for the reconstruction of cervical lordosis and the restoration of intervertebral height after corpectomy. The PolyEtherKetoneEtherKetoneKetone (PEKEKK) is a semicrystalline thermoplastic polymer that can be reinforced with carbon fibers to create long and highly fenestrated rectangular cervical cages for corpectomy. This study aimed to evaluate the radiological outcomes of an innovative PEKEEKK cage compared with others grafting options. Forty-five consecutive patients who underwent surgery with PEKEKK cages between 2017 and 2019 at a spine institution, were matched with 15 patients with a titanium mesh cylindrical cage (TMC) and 15 patients with a tricortical structural iliac bone graft. The restoration of vertebral height and cervical lordosis postoperatively, and subsidence of the construct were evaluated. Complications were reported. The minimal follow-up was 5.1±2years. A better, but nonsignificant, postoperative gain in height was observed for PEKEKK (+8.1 ± 20%) and TMC cages (+8.2 ± 16%) than for iliac crest autograft reconstruction (+2.3 ± 15%, P = 0.119). The mean subsidence at the last follow-up was greater for TMC cages (-10.2 ± 13%), but was not significant, with -6.1 ± 10% for PEKEKK cages and -4.1 ± 7% for iliac crest autografts (P = 0.223). The gain in segmental cervical lordosis was significant (P < 0.001) and remained stable in all the groups. Although an improvement in radiologic anatomical parameters can be achieved with all cage groups, the PEKEKK cage can be considered as a safe alternative for reducing subsidence. [ABSTRACT FROM AUTHOR]

In coastal areas, due to their special geological conditions, soft soil foundation has become a common form of foundation in engineering construction. Soft soil foundation has low bearing capacity and large settlement deformation, posing a serious threat to surrounding building facilities and human life and property. Therefore, monitoring it is crucial. However, the inherent characteristics of soft soil foundation make it difficult to monitor, and traditional monitoring methods have shortcomings such as poor timeliness, low manual efficiency, and difficulty in sharing monitoring data. Therefore, in practical engineering, a combination of manual and automated methods is often used for monitoring. With the advancement of technology and the development of new technologies such as artificial intelligence, applying intelligent systems to soft soil foundation monitoring, real-time monitoring and early warning have become a new research direction. This article took a coastal soft soil foundation project as an example to introduce the application of intelligent systems in this project. [ABSTRACT FROM AUTHOR]

Cage subsidence after lumbar fusion can lead to many adverse outcomes. Low bone mineral density (BMD) is a widely recognized risk factor for cage subsidence. Conventional methods can predict and evaluate BMD, but there are many shortcomings. Recently, MRI-based assessment of bone quality in specific parts of the vertebral body has been proposed, including scores for vertebral bone quality (VBQ) and endplate bone quality (EBQ). However, the predictive accuracy of the two scoring systems for cage subsidence after transforaminal lumbar interbody fusion (TLIF) remains unknown. Therefore, we investigated MRI-based VBQ and EBQ scores for assessing bone quality and compared their predictive value for cage subsidence after TLIF. To compare the predictive value between MRI-based VBQ and EBQ scores for cage subsidence after TLIF. A retrospective case-control study. Patients with degenerative lumbar diseases underwent single-level TLIF at our medical center between 2014 and 2020, all of whom had preoperative MRIs available. Cage subsidence, disc height, VBQ score, EBQ score, upper and lower vertebral body bone quality (UL-VBQ) score. Data were retrospectively examined for a consecutive sample of 346 patients who underwent TLIF at our medical center between 2014 and 2020. Patients who subsequently experienced cage subsidence or not were matched to each other based on propensity scoring, and the two matched groups (52 patients each) were compared using conditional logistic regression to investigate the association between the potential radiographic factors and cage subsidence. Scores for VBQ and EBQ were assessed for their ability to predict cage subsidence in the matched patients based on the area under the receiver operative characteristic curve (AUC). Among matched patients, those who suffered cage subsidence had significantly higher VBQ score (3.7 vs 3.1, p<.001) and EBQ score (5.0 vs 4.3, p<.001), and regression linked greater risk of subsidence to higher VBQ score (OR 4.557, 95% CI 1.076–19.291, p=.039) and higher EBQ score (OR 5.396, 95% CI 1.158–25.146, p=.032). A cut-off VBQ score of 3.4 predicted the cage subsidence among matched patients with an AUC of 0.799, sensitivity of 84.6%, and specificity of 69.2%. A cut-off EBQ score of 4.7 predicted subsidence with an AUC of 0.829, sensitivity of 76.9%, and specificity of 82.7%. Higher VBQ and EBQ scores are associated with a greater risk of cage subsidence following TLIF, and EBQ may perform better because of greater specificity. [ABSTRACT FROM AUTHOR]

Nile Delta has been historically targeted for various types of human activities since the Pharaohs' era due to abundance of its natural resources. The increasing land subsidence in the northern delta is a significant concern for the Egyptian government. Moreover, the cumulative subsidence coupled with the scenarios of sea level rise worsens the situation. In the present work, we utilize SNAPPING service on the Geohazards Exploitation Platform (GEP) to measure the spatial and temporal trends, as well as the extent of subsidence in urban areas within the Nile Delta. The study analyzed the period between 2015 and 2020 using 225 Copernicus Sentinel-1 radar imagery using the Persistent Scatterers Interferometry (PSI) technique and reported surface motion with an average of −5 mm/year in the Nile Delta surface. Subsidence is relatively higher in the eastern part with more patterns specific to particular regions. The northern part recorded subsidence ranged from 0 to 7 mm/year. High rates of subsidence up to 17 mm/year localized in locations of Port Said, Damietta, Ad Dakahlia and Al Sharkia governorates and around Manzala Lake. On the other side, medium uplift rates up to 6 mm/year concentrated around Bardaweel Lake, Parts of Ismailia governorate and Baltim city. On-site visual inspections in these areas documented tilting in buildings and clear cracks which confirm the impact of land subsidence on the structural integrity of the buildings. The GEP platform and the SNAPPING service demonstrated the capability of cloud-based solutions to provide precise surface motion information within a short time. [ABSTRACT FROM AUTHOR]

Land subsidence (LS) due to natural processes or human activity can irreparably damage the environment. This study employed the quasi-permanent scatterer method to detect areas with and without subsidence in the period from 2018 to 2020. In addition, 12 factors affecting subsidence were selected to detect LS-prone areas. Information gain ratio (IGR) and frequency ratio methods were used to determine the importance and weighting of various factors and sub-factors affecting subsidence. Novel approaches, including the standard adaptive-network-based fuzzy inference system (ANFIS) algorithm and its integration with the particle swarm optimization (PSO) algorithm, yielded LS maps. The models' predictive performance was assessed using statistical indexes such as the root mean square error (RMSE), area under the receiver operating characteristic curve (AUROC) and confusion matrix criteria (e.g., sensitivity, specificity, precision, accuracy, and recall). Finally, Shapley additive explanations approach was used to explore the importance of features in modeling. The findings showed that the subsidence pattern was V-shaped, averaging 321 mm/year. Ground-leveling and interferometric synthetic aperture radar measurements revealed a 0.93 correlation coefficient with a σ = 1.43 mm/year deformation rate. Based on IGR analysis, aquifer media, the decline of the water table, and aquifer thickness played pivotal roles in LS occurrences. In addition, the ANFIS-PSO model classified approximately 50.26 % of the study area as high and very high susceptibility. The AUROC values of ANFIS-PSO and ANFIS models for the training dataset were 0.912 and 0.807, respectively. For the testing dataset, the ANFIS-PSO model produced a higher AUROC value of 0.863, while the ANFIS model had a value of 0.771. In addition, the RMSE values for the ANFIS-PSO model were lower. Given its remarkable accuracy, the ANFIS-PSO model was deemed suitable for evaluating subsidence susceptibility in the study area. [ABSTRACT FROM AUTHOR]

Lumbar spinal fusion is a common surgical procedure that can be done with a variety of different instrumentation and techniques. Despite numerous research studies investigating subsidence risk factors, the impact of cage placement on subsidence is not fully elucidated. This study aims to determine whether placement of an expandable transforaminal lumbar interbody fusion cage at the center end plate or at the anterior apophyseal ring affects cage subsidence. A transforaminal lumbar interbody fusion cage was placed centrally or peripherally between 2 synthetic vertebral models of L3 and L4. A compression plate attached to a 10 KN load cell was used to uniaxially compress the assembly. The ultimate force required for the assembly to fail and subsidence stiffness were analyzed. Computed tomography scans of each L3 and L4 were obtained, and maximum end plate subsidence was measured in the frontal plane. Anterior apophyseal cage placement resulted in higher stiffness of the vertebrae-cage assembly (K s , 962.89 N/mm) and a higher subsidence stiffness (K b ,987.21 N/mm) compared with central placement (P < 0.05). Ultimate compressive load of the vertebrae-cage assembly did not increase. Moreover, the maximum subsidence depth did not significantly vary between placements. The subsidence stiffness increased with anterior apophyseal cage placement. Periphery end plate cortical bone architecture may play a role in resisting the impact of cage subsidence. To fully understand the effect of cage placement on cage subsidence, future studies should investigate its implications on native and diseased spine. [ABSTRACT FROM AUTHOR]

This is the first study to evaluate the predictive value of the cervical vertebral bone quality (VBQ) score on zero-profile cage (ZPC)subsidence after anterior cervical discectomy and fusion (ACDF) using the Hounsfield units (HU) value of computed tomography as the reference. A total of 89 patients with at least 1 year of follow-up who underwent single-level ACDF with ZPC were retrospectively and consecutively included. VBQ and HU value were determined from preoperative T1-weighted magnetic resonance imaging and computed tomography. Subsidence was defined as ≥2 mm of migration of the cage into the superior or inferior endplate or both using lateral cervical spine radiography. The results were subjected to statistical analysis. Subsidence was observed among 16 of the 89 study patients (Subsidence rate: 18.0%). The mean VBQ score was 2.94 ± 0.820 for patients with subsidence and 2.33 ± 0.814 for patients without subsidence. The multivariable analysis demonstrated that only an increased VBQ score (odds ratio: 1.823, 95% confidence interval : 0.918,3.620, P = 0.001) was associated with an increased rate of cage subsidence. There was a significant and moderate correlation between HU and VBQ (r = −0.507, P < 0.001). Using receiver operating characteristic curves, the area under the curve was 0.785, and the most appropriate threshold of VBQ was 2.68 (sensitivity 72.7%, specificity 82.1%). The VBQ score may be a valuable tool for independently predicting ZPC subsidence after single-level ACDF. [ABSTRACT FROM AUTHOR]

Land subsidence is a natural disaster caused by the extraction of the earth's material strength on the surface that causes the earth's surface to settle and sink. Land subsidence can also result in significant financial losses since it causes structural damage and expensive maintenance costs for roads, trains, barriers, pipelines, ground water, oil, natural gas, mines, and buildings. The Geographic Information System (GIS) and Google Earth Platform (GEP) can be used to map this land subsidence. This provides a comprehensive view of land pattern subsidence and its interactions with other geographical elements. It applies to both progressive subsidence caused by fluid extraction (groundwater, oil, or natural gas) and rapid surface subsidence caused by the collapse of an underground mine. Risk mitigation is the most effective way to deal with the experimental model. This research study focuses on the use of Predictive Data Analysis (PDA), a powerful environment in data analytics that provides a set of tools that make it easier to evaluate optimal models. The proposed model makes use of a dataset that includes specific land subsidence circumstances as input. The prediction result is achieved using a hybrid machine learning technique that combines Stochastic Gradient Descent (SGD) with Long Short-Term Memory (LSTM) and is compared to K-Nearest Neighbor (KNN), Generative Adversarial Network (GAN), and Artificial Neural Network (ANN). The proposed system employs LSTM and SGD as optimizers, resulting in a hybrid model that improves accuracy. Among the four algorithms investigated the LSTM-SGD network has the highest accuracy (97%), followed by KNN (96%), GAN (90%), and ANN (89%). Due to their ability to capture complicated nonlinear correlations in data and manage temporal dependencies, optimized hybrid ML models LSTM-SGD and KNN models appear to be particularly well-suited for land subsidence prediction. [ABSTRACT FROM AUTHOR]

To compare the effect of different Modic changes (MC) grades on the cage subsidence rate after spinal interbody fusion surgery. We comprehensively searched the PubMed, Embase, and Web of Science databases from inception to August 13, 2023, for relevant randomized controlled trials and prospective and retrospective cohort studies. Review Manager 5.3 and STATA13.0 were used to conduct this meta-analysis. The subsidence rate was assessed using relative risk and 95% confidence intervals. Six studies with a total of 716 segments were allocated to four groups according to the type of MC. The subsidence rate in the non-Modic changes (NMC) was significantly lower than that in the MC. The subsidence rate in the NMC was significantly lower than that in the MC in the subgroup of cages with extra instrumentation. No significant difference was identified between the 2 groups in the oblique lumbar interbody fusion subgroup. The subsidence rate in the NMC was significantly lower than that in the MC in the transforaminal lumbar interbody fusion subgroup. The subsidence rate in the NMC was significantly lower than that in the MC1 and MC2. We found no significant difference between NMC and MC3, MC1 and MC2, MC1 and MC3, or MC2 and MC3. MC may be associated with a higher cage subsidence rate. With the increase in MC grades, the incidence of subsidence decreased gradually, but it was always higher than that in the NMC. Oblique lumbar interbody fusion may be a better choice for the treatment of lumbar degenerative disease with MC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual diagnosis of the plausibility of internal and external impact factors. • Optimal segmentation subsidence rates of PS-InSAR for susceptibility mapping. • SHAP provides insights into factor contribution to potential land subsidence. Land subsidence in urban settlements is globally becoming prevalent and severe due to sea level rise and accelerated construction. However, few studies have analyzed the susceptibility of land subsidence in urban settlements and the subsidence rate thresholds that have a great impact on the reliability of the land subsidence susceptibility map (LSSM). This work aims to provide a novel LSSM framework for decision makers to conduct risk control in regional urban settlements. Herein, the COSMO-SkyMed Synthetic Aperture Radar (SAR) data from July 2016 to June 2021 was acquired for remote sensing interpretation in Wuhan, China. Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) technology, combined with geostatistical analysis, was employed to map regional land subsidence rates. A total of 12 impact factors, identified through Pearson correlation coefficient (PCC) and multicollinearity tests, were selected as input features for the machine learning model. The performance of the model was assessed using Receiver Operating Characteristic (ROC) curves, and the segmentation of PS points for land subsidence rate was discussed. Furthermore, the correspondence between the measured ground-level observations and the predicted LSSM was compared. The results demonstrate that the random forest (RF) model outperforms other models in the test set, achieving an Area Under the Curve (AUC) of 0.940. The optimal threshold of −10 mm/year is proposed for segmenting PS points, which exhibits the strongest reliability in the distribution characteristics of the susceptibility index (SI). Combined with a high-performance hybrid model, this work is expected to provide a promising reference for land subsidence susceptibility prediction in similar urban settlements worldwide. [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the subsidence performance of a bioactive glass-ceramic (CaO-SiO 2 -P 2 O 5 -B 2 O 3) spacer in terms of its modulus of elasticity and contact area using mechanical tests and finite element analysis. Three spacer three-dimensional models (Polyether ether ketone [PEEK]-C: PEEK spacer with a small contact area; PEEK-NF: PEEK spacer with a large contact area; and Bioactive glass [BGS]-NF: bioactive glass-ceramic spacer with a large contact area) are constructed and placed between bone blocks for compression analysis. The stress distribution, peak von Mises stress, and reaction force generated in the bone block are predicted by applying a compressive load. Subsidence tests are conducted for three spacer models in accordance with ASTM F2267. Three types of blocks measuring 8, 10, and 15 pounds per cubic foot are used to account for the various bone qualities of patients. A statistical analysis of the results is conducted using a one-way Analysis of variance and post hoc analysis (Tukey's Honestly Significant Difference) by measuring the stiffness and yield load. The stress distribution, peak von Mises stress, and reaction force predicted via the finite element analysis are the highest for PEEK-C, whereas they are similar for PEEK-NF and BGS-NF. Results of mechanical tests show that the stiffness and yield load of PEEK-C are the lowest, whereas those of PEEK-NF and BGS-NF are similar. The main factor affecting subsidence performance is the contact area. Therefore, bioactive glass-ceramic spacers exhibit a larger contact area and better subsidence performance than conventional spacers. [ABSTRACT FROM AUTHOR]

The Aswan High Dam, located in southern Egypt, is considered one of the most strategic engineering structures in Egypt. After its full operation of the dam in 1971, a series of micro-earthquakes occurred around the High Dam. The largest seismic event recorded in the region was in November 14, 1981, earthquake with a magnitude of 5.6 M L , located 60 km to the southwest of the dam. Due to the great importance of this area, a combination of remote sensing (InSAR) and terrestrial data (precise leveling) was used to shed light on the current state of crustal deformation in this area. The data collected from three leveling lines (six campaigns) covering the period 2013–2022 in addition to 107 SAR scenes (2017–2021) from the Sentinel-1 mission were used to estimate the up-to-date ground deformation of the study area. The results from both Small Baseline Subset (SBAS) and leveling measurements show that the fault normal velocity of the Spillway fault is approximately 3 ± 0.15 mm/yr. The obtained results coincide with the seismicity pattern recorded in the study area, as the seismic events close to the dam are characterized by normal fault mechanisms. Outcomes show the importance of combining terrestrial (leveling) and space geodetic techniques (InSAR) to map the active faults and estimate the deformation rates along these faults. [ABSTRACT FROM AUTHOR]

Küçük Menderes River Basin (KMRB) is located in the western part of Turkey in the city of İzmir. The basin hosts about half a million people and 90% of the population makes their living from farming and animal husbandry. Most of the water needs for agricultural irrigation, animal husbandry, and drinking are met from groundwater resources in the basin. Since the water pumped from the aquifers cannot be naturally recharged by surface waters and precipitation, the groundwater level is rapidly receding and a decrease of up to 150 meters has been observed in the historical groundwater level time series since the 1990s. For this reason, land subsidence occurred in the basin and as a result of this, crustal surface cracks have formed and infrastructure and superstructure facilities have been endangered. To prevent loss of life and property that may occur in the future, it has become necessary to estimate the magnitude and the expansion zone of the land subsidence by carrying out geodetic monitoring studies in the region. In this study, the analyzes performed by Interferometric Synthetic Aperture Radar-Small Baseline Subset (InSAR-SBAS) and Global Navigation Satellite System (GNSS) methods to monitor land subsidence in the KMRB are presented. For this purpose, monthly 74 SAR images from 2017 to the end of 2022 were evaluated according to the SBAS procedure in the GMTSAR academic analysis software. In order to, both validate the InSAR-SBAS results and convert the deformation rate in the Line of Sight (LOS) to the ellipsoid normal direction, 3 periods of GNSS campaign were performed between 2021 and 2023 in 5 different GNSS stations and evaluated with the GAMIT/GLOBK software. According to the analyses, the land subsidence rate of up to −165 mm/year has been estimated in the KMRB, especially in the district centers of Bayındır and Ödemiş. In addition, unlike many studies, different rates and propagation of subsidence were determined in different parts of the basin depending on the aquifer type and precipitation. Monthly time series of the deformations were created and the behavior of the deformations and its relationship with the groundwater withdrawal and the lithological structure in the region was scrutinized. Thus, the spatio-temporal behaviour of the land subsidence and the associated geological factors were revealed. [ABSTRACT FROM AUTHOR]

The use of static cages for lumbar interbody fusion (LIF) can cause complications such as end plate violation, graft subsidence, and nerve injury. Therefore, expandable cages that allow for in-situ expansion have been developed to overcome these problems. However, it remains uncertain whether expandable cages have better surgical outcomes than static cages do. We aimed to determine the effectiveness of expandable cages by analyzing studies that compared the surgical outcomes between the use of expandable cages and static cages. A systematic review and meta-analysis. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used to conduct this meta-analysis and systematic review. The primary outcomes of this study were anterior disc height, posterior disc height, segmental lordosis (SL), lumbar lordosis (LL), subsidence rate, numeric rating scale (NRS) scores for back and leg pain, and Oswestry Disability Index (ODI). Thirteen studies with 1,700 patients were included in the meta-analysis. Compared with static cages for LIFs, expandable cages significantly increased the anterior disc height (standardized mean difference 0.478, 95% confidence interval [CI] 0.088–0.867, p=.0162) and segmental lordosis (sMD 0.307, 95% CI 0.159–0.454, p<.0001). There were no significant differences in the posterior disc height, lumbar lordosis, subsidence rate, back pain, leg pain, or ODI between the two groups. Expandable cages show no clear clinical benefit over static cages. [ABSTRACT FROM AUTHOR]

Cage subsidence following transforaminal lumbar interbody fusion (TLIF) has closely correlated with poor vertebral bone quality. Studies have shown better predictive value for cage subsidence by measuring bone density at specific site. However, few studies have been performed to examine the relationship between site-specific MRI bone assessment and cage subsidence in patients who have undergone lumbar interbody fusion. The association between MRI-based assessment of endplate bone quality and cage subsidence after TLIF remains unclear. To study the predictive value of MRI-based endplate bone quality (EBQ) score for cage subsidence following TLIF, using QCT bone densitometry as a reference standard. A retrospective study. A total of 280 adult patients undergoing single-segment TLIF for degenerative lumbar spine disease from 2010 to 2020 at our institution who had preoperative T1-weighted MRIs. Cage subsidence, disc height, endplate bone quality (EBQ) score, bone mineral density, fusion rate. The retrospective study reviewed patients who underwent TLIF at one institution between March 2010 and October 2020. Cage subsidence was measured with postoperative lumbar X-rays based on the cage protrusion through into the superior or inferior end plate or both by more than 2 mm. The EBQ score was measured from preoperative T1-weighted MRI in accordance with the previously reported method. Cage subsidence was observed in 42 of the 280 patients. Bone densitometry with quantitative computed tomography was visibly reduced in the subsidence group. The mean EBQ scores of the lumbar endplate bone was 4.3±0.9 in nonsubsidence and 5.0±0.6 in subsidence. On multivariate logistic regression, the difference between the two groups was remarkable. Risk of cage subsidence increases significantly with higher EBQ scores (odds ratio [OR]=2.063, 95% confidence interval [CI] 1.365–3.120, p=.001) and was an independent factor in predicting subsidence after TLIF. On receiver operating characteristic curve, the AUC for the EBQ score was 0.820 (95% confidence interval [CI]: 0.755–0.844) and the most suitable threshold for the EBQ score was 4.730 (sensitivity: 76.2%, specificity: 83.2%). Higher EBQ scores measured on preoperative MRI correlated significantly with cage subsidence following TLIF. Performing EBQ assessment prior to TLIF may be a valid method of predicting the risk of postoperative subsidence. [ABSTRACT FROM AUTHOR]

Transforaminal lumbar interbody fusion with biportal endoscopic guidance (BE-TLIF) has been previously reported with promising clinical results. However, complications such as delayed union or subsidence occurred as with open surgery. We assumed using larger cages would result in less occurrence of such complications. We aimed to analyze the clinical outcome and technical feasibility of BE-TLIF using larger cages, initially designed for oblique lumbar interbody fusion. We enrolled cases that underwent single-level BE-TLIF between January 2021 and January 2022. Polyetheretherketone cages that were larger than the conventional size were used. Diagnoses were degenerative spondylolisthesis or isthmic spondylolisthesis. Visual analog scale scores of the back and leg and Oswestry Disability Index were collected perioperatively. Modified Macnab criteria were used to evaluate the patients at the final follow-up. Radiologic outcome of interbody fusion rate and perioperative complications were analyzed. A total of 35 cases were included in this study. The mean age was 67.5 ± 8.4 and consisted of 13 male patients, and the mean follow-up duration was 18.3 ± 3.7 months. The majority (32/35, 91.3%) of the index level was located within the lower lumbar region, L4-S1. Oswestry Disability Index scores improved from 65.4 ± 5.4 preoperatively to 15.4 ± 6.1 at the final follow-up (P < 0.001). Visual analog scale scores of the leg decreased from 7.9 ± 1.5 to 1.7 ± 1.5 at the final follow-up (P < 0.001). Per the modified Macnab criteria on the final follow-up, 94% of the patients reported good/excellent. Most (94.2%) of the patients showed fusion grade I and II at the 1-year follow-up. No patient showed subsidence or other postoperative complication. BE-TLIF using a larger cage was safely performed without risk of subsidence during the 1-year follow-up. A cage with a larger footprint may be advantageous in BE-TLIF in the aspect of interbody fusion and subsidence. [ABSTRACT FROM AUTHOR]

The occurrence of early osteointegration and reduced modulus of elasticity have been proved with 3-dimensinally (3D) printed porous titanium (3DP-titanium) cages used for posterior lumbar interbody fusion (PLIF). The present study was conducted to demonstrate the fusion rate, subsidence, and clinical outcomes for the 3DP-titanium cage in PLIF and to compare its results with those of the polyetheretherketone (PEEK) cage. A total of 150 patients who underwent 1–2-level PLIF and were followed up for >2 years were retrospectively reviewed. The fusion rates, subsidence, segmental lordosis, visual analog scale (VAS) score for back pain, VAS score for leg pain, and Oswestry disability index were assessed. A higher 1-year (3DP-titanium, 86.9%; PEEK, 67.7%; P = 0.002) and 2-year (3DP-titanium, 92.9%; PEEK, 82.3%; P = 0.037) fusion rate could be achieved with 3DP-titanium cages for PLIF than with PEEK cages. The amount of subsidence (3DP-titanium, 1.4 ± 1.6 mm; PEEK, 1.9 ± 1.8 mm; P = 0.092) and incidence of significant subsidence (3DP-titanium, 17.9%; PEEK, 23.4%; P = 0.389) was not significantly different between the 2 materials. Furthermore, the VAS score for back pain and leg pain and Oswestry disability index were not significantly different between the 2 groups. On logistic regression analysis, cage material (P = 0.027) showed a significant association with fusion, and the number of levels fused (P = 0.012) was associated with subsidence. The 3DP-titanium cage resulted in a higher fusion rate than the PEEK cage when used for PLIF. The subsidence rate did not differ significantly between the 2 cage materials. Therefore, the 3DP-titanium cage can be safely used for PLIF, considering its stable construct. [ABSTRACT FROM AUTHOR]

Human societies face significant difficulties in the governance of environmental land-use problems. The challenges involved must be thoroughly understood to develop effective and legitimate governance of these often inherently wicked problems. However, in environmental governance literature, governance challenges have been described rather generally, and the characteristic features of different types of problems have not been specified. Drawing on this literature, this paper presents an analytical framework for governance challenges typical of a "wicked problem" and a "creeping crisis". We empirically illustrate the combined framework by applying it to the environmental land-use problem of land subsidence in the Dutch peatlands. Land subsidence exemplifies a wicked problem because it is neither definable nor solvable. Due to the lack of effective governance, the problem has allowed threats with crisis potential to develop. However, land subsidence represents a "creeping" crisis because, despite the increasing risk of damage, there is little sense of urgency. The case study illustrates that governance challenges posed by such problems often originate from a lack of comprehensive sense-making of these problems' complexity and that responses, therefore, tend to be counterproductive. Hence, the paper empirically substantiates the need for governance approaches that help achieve the systemic change that is arguably needed to address environmental land-use problems adequately. • Environmental land-use problems are typical wicked problems and creeping crises. • Our analytical framework includes governance challenges typical to these problems. • Challenges often originate from a lack of comprehensive sense-making of complexity. • Counterproductive governance responses are simplification, silo-mentality, paralysis. • Responsibilization, mainstreaming and experimentation are more suitable approaches. [ABSTRACT FROM AUTHOR]

The purpose this study was to precisely characterize patterns of allograft subsidence following anterior cervical discectomy and fusion (ACDF) utilizing computed tomography scans, determine risk factors for cervical allograft subsidence, and investigate the impact of subsidence on pseudarthrosis rates. We performed a retrospective review of patients undergoing 1-to 3-level ACDF utilizing allograft interbodies with anterior plating between 2011 and 2019. Subsidence measurements were performed by 2 independent reviewers on computed tomography scans obtained 6 months postoperatively. Subsidence was then classified as mild if subsidence into the inferior and superior endplates were both ≤2 mm, moderate if the worst subsidence into the inferior- or superior endplate was between 2 and 4 mm, or severe if the worst subsidence into the inferior- or superior endplate was ≥4 mm. Multivariate analysis was performed to identify risk factors for the development of subsidence. We identified 98 patients (152 levels) for inclusion. A total of 73 levels demonstrated mild subsidence (≤2 mm), 61 demonstrated moderate subsidence (2–4 mm), and 18 demonstrated severe subsidence (≥4 mm). On multivariate analysis, risk factors for severe subsidence included excessive vertebral endplate resection and lower screw tip to vertebral body height ratio. Severe subsidence was associated with an increased rate of pseudarthrosis (94.1% vs. 13.6%) without an associated increase in reoperation rate. Following ACDF with allograft interbodies, 50% of interbodies will subside >2 mm and 10% of interbodies will subside >4 mm. Risk factors for severe subsidence should be mitigated to decrease the risk of pseudarthrosis. [ABSTRACT FROM AUTHOR]

The effect of psoas and paraspinal muscle parameters on cage subsidence after minimally invasive techniques, such as standalone lateral lumbar interbody fusion (SA-LLIF), is unknown. This study aimed to determine whether the functional cross-sectional area (FCSA) of psoas and lumbar spine extensor muscles (multifidus and erector spinae), and psoas FCSA normalized to the vertebral body area (FCSA/VBA) differ among levels with severe cage subsidence after SA-LLIF when compared to levels without severe cage subsidence. Retrospective single center cohort study. Patients who underwent SA-LLIF between 2008 and 2020 for degenerative conditions using exclusively polyetheretherketone (PEEK) cages, had a lumbar magnetic resonance imaging (MRI) scan within 12 months, a lumbar computed tomography (CT) scan within 6 months prior to surgery, and a postoperative clinical and radiographic follow-up at a minimum of 6 months were included. Severe cage subsidence. MRI measurements included psoas and combined multifidus and erector spinae (paraspinal) FCSA and FCSA/VBA at the L3-L5 pedicles. Following manual segmentation of muscles on axial T2-weighted images using ITK-SNAP (version 3.8.0), the FCSA was calculated using a custom written program on Matlab (version R2019a, The MathWorks, Inc.) that used an automated pixel intensity threshold method to differentiate between fat and muscle. Mean volumetric bone mineral density (vBMD) at L1/2 was measured by quantitative CT. The primary endpoint was severe cage subsidence per level according to the classification by Marchi et al. Multivariable logistic regression analysis was performed using generalized linear mixed models. All analyses were stratified by biological sex. 95 patients (45.3% female) with a total of 188 operated levels were included in the analysis. The patient population was 92.6% Caucasian with a median age at surgery of 65 years. Overall subsidence (Grades 0-III) was 49.5% (53/107 levels) in men versus 58.0% (47/81 levels) in women (p=.302), and severe subsidence (Grades II-III) was 22.4% (24/107 levels) in men versus 25.9% (21/81 levels) in women (p=.608). In men, median psoas FCSA and psoas FCSA/VBA at L3 and L4 were significantly greater in the severe subsidence group when compared to the non-severe subsidence group. No such difference was observed in women. Paraspinal muscle parameters did not differ significantly between non-severe and severe subsidence groups for both sexes. In the multivariable logistic regression analysis with adjustments for vBMD and cage length, psoas FCSA at L3 (OR 1.002; p=.020) and psoas FCSA/VBA at L3 (OR 8.655; p=.029) and L4 (OR 4.273; p=.043) were found to be independent risk factors for severe cage subsidence in men. Our study demonstrated that greater psoas FCSA at L3 and psoas FCSA/VBA at L3 and L4 were independent risk factors for severe cage subsidence in men after SA-LLIF with PEEK cages. The higher compressive forces the psoas exerts on lumbar segments as a potential stabilizer might explain these findings. Additional pedicle screw fixation might be warranted in these patients to avoid severe cage subsidence. [ABSTRACT FROM AUTHOR]

The effect of clay layer compression on the enrichment of groundwater fluoride remains unknown. Quaternary groundwater with high fluoride levels at the Cangzhou Plain, which has a long history of land subsidence caused by clay layer compression, poses a potential health risk. The spatial distribution and enrichment mechanisms of groundwater fluoride are identified by sample collection, hydrochemical analysis, and geochemical inverse modeling. The results revealed that fluoride concentrations in 82 % of the 122 groundwater samples above the limit in drinking water as 1.0 mg/L in China. Fluoride in shallow groundwater (depth < 20 m, ∼average = 2.08 mg/L) was mainly originated from fluorite dissolution and influenced by groundwater HC O 3 − , pH, and cation exchange levels. Below ∼200 m, the main source of groundwater fluoride (∼average = 3.12 mg/L) was the compression−release of clay pore water with high F− concentration, which was generated by complex water-rock interaction. Based on hydrochemical inverse simulation and end-member mixing models, the pore water released from clayey sediments supplied 53 %−56 % of deep groundwater (>200 m) and contributed 2.07 −2.87 mg/L to F− concentration. The findings of this study provide a theoretical basis for future research on prevention of high fluoride groundwater induced by clayey sediment compression. [Display omitted] • High fluoride groundwater distributed mainly in the subsidence area of the CZP. • The fluoride in shallow groundwater mainly originates from the fluorite dissolution. • Release of clay pore water promotes the enrichment of fluoride in deep groundwater. • The abundant fluoride in clay pore water was formed by water-rock interaction. • Clay layer compression has a significant contribution to groundwater F− content. [ABSTRACT FROM AUTHOR]

Most of the land subsidence numerical models introduced in the literature are based on limiting assumptions, such as one-dimensional land movement, uncoupled formulations, and linear elasticity; and some even does not satisfy mass conservation requirements. As a result, many of the models may fail to realistically and efficiently represent the behavior of the porous media undergoing hydraulic loading. In this study, a locally conservative numerical technique is proposed for the analysis of land subsidence in saturated porous media in both the plane strain and axisymmetric conditions. To this end, the flow equation, discretized using a dual discrete finite volume method, is coupled iteratively with the elastoplastic deformation model, solved using the finite element method. The developed model is then verified, and its benefits compared to the standard finite element method, are discussed. The application of the proposed method is further demonstrated through a quasi-real conceptualization of a multi-aquifer system, considering the effect of different seasonal pumping schedules. The results show that soil deformations in the horizontal direction may be as large as those in the vertical direction and cannot be neglected. It is also shown that the pumping schedule can have considerable effects on the land subsidence regime. [ABSTRACT FROM AUTHOR]

• Analogue experiments confirm the effect of isostacy on crater floor fracture formation by upward flexing of crater floors. • Long-term relaxation of crust below craters and their periphery is caused by lower crustal flow toward crater centres. • The geometry of floor fractures caused by relaxation depends on crater diameters and crustal strength. Crater floor fractures are prominent post-cratering structural vestiges that are known from large impact craters on rocky celestial bodies. Two mechanisms have been proposed to explain the formation of crater floor fractures: emplacement of horizontal igneous sheets below crater floors and isostatic re-equilibration of crust underlying target rocks, i.e., crustal relaxation. Here, we use two-layer analogue experiments to model the deformation of lower and upper crust following crater formation, scaled to the physical conditions on Earth, to explore the structural and kinematic consequences of crustal relaxation. Specifically, the structural evolution of model upper crust was systematically analysed for various initial depths and diameters of crater floors, gleaned from previous numerical models for average continental crust. The analogue modelling results provide quantitative estimates of the duration, geometry and distribution of deformation zones in the upper crust and, for the first time, a quantitative relationship between the diameter, depth and fracture geometry of crater floors. The experiments also show that crater floor uplift is accomplished by long-wavelength subsidence of the crater periphery, which may operate on time scales of hundreds of thousands of years in nature. We conclude that patterns of natural crater floor fractures, including impact melt rock dikes known from the Sudbury and Vredefort impact structures, can be caused by long-term uplift of the crater floor, compensated by lateral crustal flow toward the crater centre. [Display omitted] [ABSTRACT FROM AUTHOR]

• Subsidence parameters have statistically significant correlation with spreading rate. • SW Indian and Central Pacific oceans are the end-members in global subsidence trends. • Slow spreading produces narrow oceans with old seafloor age and passive margins. • Fast spreading produces wide oceans with young seafloor age and active margins. • The distribution of hotpots in oceans may be controlled by spreading rate. Ocean age-dependent cooling subsidence with seafloor deepening is traditionally described by models of thermo-chemical buoyancy of oceanic plates with globally constant parameters, that specify a linear correlation between square-root of seafloor age, sqrt(age), and bathymetry. Here I present a worldwide analysis of the ocean floor split into 94 segments, delineated by wide-offset transform faults and mid-ocean ridges, to demonstrate a strong heterogeneity of sediment-corrected isostatic cooling subsidence both between and within normal oceans. Anomalous oceans are identified from bathymetry deviation from age-dependent predictions during data processing. Subsidence parameters for individual ocean segments significantly deviate from global constants in conventional models and show a large variability of subsidence rate (270–535 m/Ma1/2) and zero-age depth (−1.30 to −3.03 km) with plate thickness estimated between 50 and 160 km for cooling models with constant mantle properties. Statistically strong correlations (R2=0.80–0.94) between major characteristics of cooling subsidence and spreading rate indicate that ocean evolution is essentially controlled by spreading rate, despite this factor is not included in conventional models of ocean subsidence. Normal oceans with slower spreading rate have, statistically, higher subsidence rate which implies faster gravitational collapse caused by faster plate cooling with moderate-to-low mantle temperatures at mid-ocean ridges. Fast-spreading oceans have the opposite characteristics. The ultraslow SW Indian and the fast-spreading Central Pacific Oceans are the end-members in ocean cooling subsidence trends, with the Atlantic/NW Indian Oceans tending towards the ultraslow end, and the Pacific/SE Indian Oceans being closer to the fast-spreading end. The Arctic Ocean and the Atlantics north of the Charlie-Gibbs Fracture Zone with an atypical subsidence behavior often deviate from the global trends. Strong correlation between spreading rate, ocean half-width and the type of ocean margins implies that ridge-push dominates tectonic forces in slower-spreading, narrower oceans with passive margins, while slab-pull at active margins is a dominant tectonic force in faster-spreading oceans with half-width exceeding 4250 km. The age of bathymetry departure from cooling subsidence, controlled by distribution of hotspots on ocean floor, correlates (R2=0.76) with spreading rate, and thus is not fully random. Slower-spreading oceans follow normal cooling subsidence to older ages (7.5–9.5 Ma1/2) than faster-spreading oceans (5–7 Ma1/2). Recognition that spreading rate controls ocean evolution with formation of active or passive ocean margins dominated by slab-pull or ridge-push contributes to advances in understanding driving forces in geodynamics. [Display omitted] [ABSTRACT FROM AUTHOR]

Coal has been crucial in driving economic development and production construction. However, the mining-induced subsidence may cause irreversible damage to the surrounding environment of vegetation growth. Meanwhile, with the worsening of global warming, the frequency and intensity of extreme water-related weather events, such as droughts and excessive rainfall, are on the rise, which leads to heightened impacts on ecosystems and agricultural production. Consequently, extreme water-related weather, the distribution of land subsidence, and its effect on vegetation have attracted significant attention. Based on the Sentinel-1 radar data and Sentinel-2 multispectral data from 2017 to 2022, the SBAS-InSAR technology, the object-oriented classification, and the Normalized Difference Vegetation Index (NDVI) were employed respectively in the study to obtain the spatial-temporal evolution of land subsidence, subsidence-induced water, and crop growth in Tiefa mining area, a representative coal mining area in Northeast China. Moreover, the relationship between land subsidence, subsidence-induced water, and vegetation change was analyzed combined with summer precipitation data. The results showed that: (1) The average cumulative subsidence of the mining area was 256.8 mm, and the subsidence area was 42.525 km2 for the six years. Among them, the heaviest subsidence reached a maximum of 380.5 mm in 2022, and the largest subsidence area was 20.109 km2 in 2017. (2) When the rainfall was excessive, the area of subsidence-induced water would increase sharply, with a proportion jumping to 9.71% from 5.37%, which indicated the subsidence would further amplify the destructive effect of excessive rainfall and waterlogging on land resources. (3) In addition to the existing water pits, ground cracks and shallow subsidence pits appeared under the influence of underground coal mining. The direct impact of ground cracks on crops was not apparent, while the effect of subsidence pits on crops under different rainfall conditions was dual character. In dry years, crops in the subsidence pits could grow better due to higher soil moisture. In wet years, crops in the subsidence pits would suffer the more severe waterlogging. The research results are of great significance for further understanding the influence of coal mining on surface vegetation in mining areas in Northeast China. • Underground coal mining would cause severe surface subsidence to cultivated land. • Surface subsidence would further amplify the destructive effect of excessive rainfall and waterlogging on land resources. • The impact of shallow subsidence pits on crops under different rainfall conditions was dual character. • The affected crops in drought years decreases with the increase of subsidence amount. [ABSTRACT FROM AUTHOR]

This paper presents evidence of distressed property spillover in coastal flood-prone areas. By utilizing a hedonic pricing model, this study may contribute to the global discussion on how property markets react to deterioration in coastal areas, specifically from the perspective of the Global South. Spillover effects in housing prices were observed through a spatial autoregressive model by investigating lags in price adjustment over time and space. The authors employed two large datasets comprising property information, including property tax history (n = 1933,037; 1993–2020) and real estate transactions (n = 1029; 2013–2020). These datasets are also recorded in the cadaster map of the Indonesian government. The property tax history provides crucial evidence regarding delinquent taxes, signifying distressed properties abandoned by their inhabitants. Property sales transaction data offers evidence of lowered prices and their spillover effects. As a result, this paper contends that neighborhood decay induced by coastal flooding represents a non-economic shock that permeates to the property market, leading to price movement. The most important finding is that land subsidence has a more significant influence than distressed properties on lowering prices and their spillover effects. These findings have the potential to initiate new discussions about environmental deterioration from a property market perspective. • Spillover in coastal flood-prone areas. • Hedonic Pricing Model. • Submarket for distressed properties. • Spatial autoregressive Model. • Developing countries. [ABSTRACT FROM AUTHOR]

The surface conductor is the first structural casing in deepwater natural gas hydrate (NGH) development, bearing the top load while suspending the casings of various layers. NGH decomposition leads to formation settlement, changing the mechanical properties of the formation and reducing the bearing capacity of the surface conductor, threatening the safety and stability of the wellhead. Understanding the bearing characteristics of the surface conductor in the hydrate formation can guide the safe drilling operation in the field. By introducing the negative skin friction theory of pile foundations and based on conventional bearing capacity models, a method for calculating the bearing capacity of surface conductors in NGH formations was developed. Using an NGH drilling simulation apparatus, the accuracy of the bearing capacity theoretical model was verified, empirical coefficients under different conditions were obtained, and the influence of soil parameters, hydrate saturation, and decomposition temperature on the bearing capacity of surface conductors was quantified. The results indicated that compared to clay, sandy soils have higher porosity and significantly weakened strength after the decomposition of NGH; when the hydrate saturation in the formation is 20%, the reduction in bearing capacity of the surface conductor in sand exceeds 30%, and in clay soils, it decreases by 25% after complete decomposition of NGH; as the hydrate saturation increases, the reduction in the bearing capacity of surface conductors after decomposition becomes more significant. Verified through Experimentation, the error of the hydrate-bearing strata-bearing capacity model is around 10%. For short-term test production operations of NGH in water, the design depth for surface conductors is around 100 m. These research results can provide a scientific theoretical basis for the design of conductor depth below the mud， and reduce operational risks. • A model calculates surface conductor bearing capacity in hydrate formations based on pile and subsidence theories. • The model for conductor bearing in hydrate formations was validated experimentally and analyzed for various factors. • Based on the engineering load, the design method of surface conductor in hydrate formation is established. [ABSTRACT FROM AUTHOR]

The Miocene is a crucial epoch in the evolution of the Gulf of Suez basin. Its deposits experienced rapid and distinct spatial and temporal variations in facies and thickness due to deposition in a complex system of fault-bounded sub-basins that were continuously active throughout most of the Miocene. This review addresses the evolution of Miocene facies in the Gulf of Suez, which remains a major challenge, by integrating a detailed stratigraphic and sedimentological study. Two markedly different facies characterize Miocene deposits: marginal and deeper marine facies. Regionally traced unconformities intersect these facies, reflecting the nature of the tectonically active rift basin in which they accumulated. They define seven depositional sequences in the lower and middle Miocene facies exposed along the rift margins. Unconformities and related sea-level falls formed in response to major rift events, although some are associated with eustatic sea-level falls. The latter played an important role during the rift abandonment, when tectonic subsidence was slow. The evolution of Miocene facies reveals three distinct phases of rifting, each showing unique subsidence rate, sedimentation rate, structural relief, depositional systems, and facies architectures. These phases define four depositional stages, including the shallow marine stage, the open marine stage, the transitional stage, and the restriction stage. The first stage displays slow tectonic subsidence and initial marine invasion during the Aquitanian–early Burdigalian (Nukhul Formation). The second stage shows a rapid increase in rates of crustal extension, tectonic subsidence, and sedimentation during the early–late Burdigalian (Rudeis Formation), and a marked uplift of the rift shoulders in the late Burdigalian. The third stage indicates reduced rates of extension, subsidence, and sedimentation during the Langhian (Kareem Formation). The final stage shows a very slow subsidence with periodic water inflows from the Mediterranean during the Serravallian (Belayim Formation), and ends with an uplift in the northernmost Gulf of Suez basin that permanently isolates it from the north during the Tortonian–Messinian (South Gharib and Zeit formations). Facies attributed to the Gharamul and Gemsa formations, and the Sarbut El-Gamal Formation developed simultaneously along the western and eastern rift margins, respectively, during the second, third, and the lower part of the fourth evolutionary stages. [Display omitted] • This review accurately correlates marginal and deeper marine facies of the basin. • It provides additional chronostratigraphic data for marginal facies. • Eight unconformities attributable to rift events define seven exposed sequences. • Locally induced sea-level changes control sequences; some show eustatic signals. • Four distinct evolutionary stages characterize the Miocene facies. [ABSTRACT FROM AUTHOR]

Construction of large underground infrastructure facilities routinely leads to leakage of groundwater and reduction of pore water pressures, causing time-dependent deformation of overburden soft soil. Coupled hydro-geomechanical numerical models can provide estimates of subsidence, caused by the complex time-dependent processes of creep and consolidation, thereby increasing our understanding of when and where deformations will arise and at what magnitude. However, such hydro-mechanical models are computationally expensive and generally not feasible at larger scales, where decisions are made on design and mitigation. Therefore, a computationally efficient Machine Learning-based metamodel is implemented, which emulates 2D finite element scenario-based simulations of ground deformations with the advanced Creep-SCLAY-1S-model. The metamodel employs decision tree-based ensemble learners random forest (RF) and extreme gradient boosting (XGB), with spatially explicit hydrostratigraphic data as features. In a case study in Central Gothenburg, Sweden, the metamodel shows high predictive skill (Pearson's r of 0.9–0.98) on 25 % of unseen data and good agreement with the numerical model on unseen cross-sections. Through interpretable Machine Learning, Shapley analysis provides insights into the workings of the metamodel, which alignes with process understanding. The approach provides a novel tool for efficient, scenario-based decision support on large scales based on an advanced soil model emulated by a physically plausible metamodel. • A ML-based metamodel emulates a hydro-geomechanical model accurately. • Subsidence due to pore-pressure reductions in soft soil is estimated at large scale. • Predictions possible at high resolution with high computational efficiency. • Interpretable ML confirms that the metamodel matches physics. • Metamodels are a reliable basis for large scale infrastructure decision support. [ABSTRACT FROM AUTHOR]

The problem of land subsidence due to groundwater pumping in highly compressible, randomly heterogenous aquitards with stress-dependent parameters is analyzed through one-dimensional Monte Carlo numerical simulations of nonlinear groundwater flow and consolidation. The natural logarithm of hydraulic conductivity (Y) and compression index (C c) are considered spatially cross-correlated random variables. A stochastic simulation method based on a bivariate normal copula was applied to generate positive, negative, and uncorrelated realizations of the two random variables. The results show that when Y and C c are correlated random parameters, the ensemble average total settlement is consistently larger (between 13% and 40% for the synthetic cases tested) than the total settlement obtained when the parameters are deterministic (perfectly known). In addition, the results of negative and no correlation between Y and C c are similar in terms of the ensemble average and variance of total settlement, while positive correlation leads to larger values of total settlement and its variance. The stochastic approach employed here allows incorporating the uncertainty in the parameters in the simulation of the subsidence process, which is relevant for geotechnical engineering, design of structures and groundwater management. • We investigate the process of land subsidence in highly compressible aquitards overlying an aquifer. • The natural logarithm of hydraulic conductivity (Y) and compression index (C c) of the aquitard are spatially cross-correlated random variables. • Their joint effect on land subsidence is investigated. [ABSTRACT FROM AUTHOR]

The East African Rift System (EARS) is an active continental rift zone that hosts a diverse range of processes that result in recent and ongoing crustal deformation. To analyze these processes, we used Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR) to complement the sparse GNSS velocity field with high resolution measurements of line-of-sight (LOS) deformation between 2015 and 2022. A broad survey approach was employed to detect new signals within the central section of the EARS, and to establish a baseline for future studies focused on tectonic, volcanic, and/or hydrologic deformation and change spanning geodetic time scales. With this regional approach, we were able to resolve signals varying over time-spans of a few weeks to several years that have magnitudes greater than ∼1 cm/yr. Our resulting deformation field shows a diverse range of signals related to the processes listed above as well as other unknown sources. This includes up to 8.5 cm/yr of groundwater-related subsidence in Nairobi, up to 70 cm of LOS displacement during the eruption of Nyiragongo in 2021, and steady uplift in the Manyara basin with a rate of 2.8 cm/yr. We update previously published InSAR measurements of Mount Suswa volcano, and the geothermal fields in Olkaria. We also show LOS change ranging between 2 and 5 mm/yr over a distances of approximately 200 km spanning the Kenya Rift with the greatest differential rates occurring south of Lake Turkana. More generally, our results highlight the ambiguity of relying solely on the sparse network of GNSS for studies such as those characterizing tectonic motion and rift opening. Such studies are likely missing many important signals and/or includes sites that are contaminated with signals unrelated to the target process. • InSAR complements the GNSS velocity field in the EARS, revealing high-resolution LOS deformation between 2015 and 2022. • Identified a diverse range of volcanic, tectonic, and anthropogenic deformation signals. • Illuminated the limitations of sparse GNSS networks for comprehensive deformation analysis. [ABSTRACT FROM AUTHOR]

This paper studies the tractive rolling nanocontact occurring between an exponentially graded coating-substrate structure and a circular rigid indenter. Employing the framework of Steigmann–Ogden surface elasticity, it models the surface effects inherent in the nanocontact of graded coatings. The contact area is assumed to comprise a central stick zone bounded by two distinct slip zones. Central to the investigation is the utilization of the nonclassical Flamant solution, which serves as the foundational framework for deriving integral equations governing the continuity of both vertical and tangential displacement gradients. Utilizing Gauss–Chebyshev quadratures, the paper discretizes and collocates these integral equations, along with the force equilibrium conditions and shear traction smooth condition at the leading side stick/slip transition point. An iterative algorithm is then developed to tackle the resultant algebraic system, particularly concerning the discretized contact pressure and friction traction. The paper rigorously validates its proposed solution method and numerical algorithm against existing literature results, showcasing their accuracy and reliability. Moreover, it conducts extensive parametric studies to unravel the effects of various parameters, such as surface material properties, coefficient of friction, inhomogeneity index, and thickness of the exponentially graded coating. These analyses uncover the significant role of surface effects in shaping contact pressure, frictional traction, stresses, subsidence distributions, and stick–slip zones. Notably, the inclusion of surface effects is found to reduce maximum stress and subsidence while inducing a shift of the stick region towards the rolling direction. The parametric exploration of graded coating properties also offers insights into tailoring nanocontact responses for gradient nanostructures. • Analyzed tractive rolling nanocontact between a graded coating and a rigid punch. • Developed iterative algorithm for solving coupled integral and algebraic equations. • Surface effects lead to reduced stress, subsidence, and stick region shifts. • Friction coefficient strongly affects pressure, friction, subsidence and stresses. • Graded coating properties are crucial for tailoring nanocontact responses. [ABSTRACT FROM AUTHOR]

• Improper synchronous grouting at the shield tail in highly permeable strata can lead to mortar covering the shield shell, triggering the soil-carrying effect. • The first discovery of the soil-carrying effect in shield tunneling. • Soil-carrying increases long-term subsidence and complicates grouting volume control. • Solutions involving vibrating steel sheet piles and a new type of single-liquid slurry have been effectively applied on-site to manage mortar covering. With the rapid urbanization and infrastructure development, there is a growing demand for the construction of super-large-diameter tunnels in China. As a result, understanding the impact of tunneling on soil behavior is becoming increasingly important. This paper provides a detailed case study on the construction of a super-large-diameter shallow-buried shield tunnel in Zhuhai, China, with a special focus on the soil-carrying effect. This phenomenon, identified for the first time in shield tunneling, is triggered by the covering of solidified grouting on the shield shell during tunneling and results in a distinct pattern of soil deformation. The study explores the mechanism and disturbance characteristics of the soil-carrying effect in shield tunneling. It also examines the causes of the mortar covering that triggers this effect. Through soil monitoring data, the disturbance characteristics of the soil-carrying effect in this project are demonstrated from three aspects: longitudinal ground displacement, settlement trough, and deep horizontal displacement. The study found that when the excavation width becomes insufficient to support the departure of the shield shell and mortar covering, the overlying soil gets pushed forward with the shield tunneling progression. This leads to two distinct failure faces in the overlying soil along the longitudinal axis and poses significant challenges in controlling the volume of synchronous grouting. The monitored data from the project revealed a "wave" disturbance on the ground during shield tunneling, accompanied by passive uplift and horizontal spreading and collapse of the surrounding soil during the shield passage. To address the soil-carrying effect, the primary treatment proposed involved the installation of multiple rows of vibrating steel sheet piles. These piles help loosen and block the solidified mortar, facilitating its removal from the shield shell. Furthermore, a new type of single-liquid slurry that extends the initial setting time was introduced to prevent the reappearance of mortar covering. The effectiveness of the proposed measures was verified through subsequent monitored ground displacement. The case presented can provide warning and reference for subsequent super-large-diameter shallow-buried shield tunneling projects. [ABSTRACT FROM AUTHOR]

• The response surface experimental method is used to accurately obtain the ratio of similar materials. • The failure mechanism of the automatically formed roadway in thick-hard roof is explored. • A cooperative control technique of increasing the gangue volume in the goaf and improving the strength of coal rib is proposed. Automatically formed roadways (AFR) are highly susceptible to extreme deformation and damage under thick-hard roof geological conditions. Taking the thick-hard roof of the Yushuquan coal mine as a case study, this paper mainly studies the extreme deformation, failure mechanism, and control technology of the AFR. First of all, through on-site monitoring, the maximum vertical convergence rate of the AFR in thick-hard roof reaches 44.8 mm/d. The failure of the AFR mainly focuses on the roof sinking, coal rib rupture, and deformation of gangue prevention structure. Then, a model test was employed to analyze the deformation characteristics of the AFR, including the roadway roof, roadway floor, solid coal rib, and gangue rib. Furthermore, the failure mechanism of the AFR in thick-hard roof is explored. The model test shows that the rotation and subsidence of the roadway roof strata are the main factors causing the AFR damage. In turn, the subsidence of the roadway roof strata is controlled by the movement and distribution characteristics of the hard rock blocks within the cutting range. Eventually, cooperative control technology was proposed, including increasing the gangue volume in the goaf and increasing the coal rib strength to control the extreme deformation of the AFR in thick-hard roof conditions. Field engineering application demonstrates that the deformation of AFR surrounding rock is effectively controlled under thick-hard roof. The research findings can serve as a valuable reference for the prevention and control of the stability of AFR under complex geological conditions. [ABSTRACT FROM AUTHOR]

Cage subsidence after instrumented lumbar spinal fusion surgery remains a significant cause of treatment failure, specifically for posterior or transforaminal lumbar interbody fusion. Recent advancements in computational techniques and additive manufacturing, have enabled the development of patient-specific implants and implant optimization to specific functional targets. This study aimed to introduce a novel full-scale topology optimization formulation that takes the structural response of the adjacent bone structures into account in the optimization process. The formulation includes maximum and minimum principal strain constraints that lower strain concentrations in the adjacent vertebrae. This optimization approach resulted in anatomically and mechanically conforming spinal fusion cages. Subsidence risk was quantified in a commercial finite element solver for off-the-shelf, anatomically conforming and the optimized cages, in two representative patients. We demonstrated that the anatomically and mechanically conforming cages reduced subsidence risk by 91% compared to an off-the-shelf implant with the same footprint for a patient with normal bone quality and 54% for a patient with osteopenia. Prototypes of the optimized cage were additively manufactured and mechanically tested to evaluate the manufacturability and integrity of the design and to validate the finite element model. [Display omitted] • A novel full-scale topology optimization formulation tailored for patient-specific spinal fusion cages. • The optimized patient-specific spinal fusion cages result in anatomically and mechanically conforming devices. • Anatomically and mechanically conforming devises reduce subsidence risk compared to other cages. • The reduction in subsidence risk is 91% compared to an off-the-shelf implant for a patient with normal bone quality. [ABSTRACT FROM AUTHOR]

Although the tropical intraseaonal variability (TISV), as the most important predictability sources for subseasonal-to-seasonal (S2S) prediction, is dominated by Madden-Julian oscillation (MJO), its significant fraction does not always share the canonical MJO features, especially when the convective activity arrives at Maritime Continent. In this study, using principal oscillation pattern (POP) analysis on the combined fields of daily equatorial convection and zonal wind, two distinct leading TISV modes with relatively slower e -folding decay rates are identified. One is an oscillatory mode with the period of 51 days and e -folding time of 19 days, capturing the eastward propagating (EP) feature of the canonical MJO. The other is a non-oscillatory damping mode with e -folding time of 13.6 days, capturing a standing dipole (SD) with convection anomalies centered over the Maritime Continent and tropical central Pacific, respectively. Compared to the EP mode, the leading moisture anomalies at low level to the east of convection center are diminish for the SD mode, and instead, the strong negative anomalies of moisture and subsidence motion emerge in the tropical central Pacific area, which may be responsible for the distinct propagation features. Without filtering methods used, timeseries of the two POPs could be applied to the real-time monitoring of EP and SD events in the phase-space diagram. The two modes can serve as the simple and objective approach for a better characterization for diverse natures of TISV beyond the canonical MJO description, which may further shed light on dynamics of the TISV and its predictability. • Principal oscillation pattern (POP) analysis is used to identify the canoncial eastward propagating (EP) mode and standing dipole (SD) mode of tropical intraseasonal variability. • The strong negative moisture anomalies and subsidence that locating to the east of active convection are responsible for the distinct non-propagation features of SD mode. • Without filtering used, timeseries of the two POPs could be used for the objectively real-time monitoring of EP and SD events. [ABSTRACT FROM AUTHOR]

Although mining significantly alters land use at the local and regional levels, the relationship between mining and township land use transition requires further clarification. This study presents a critical case study from a mining township in Lianghuang, China, which quantifies the changes in dominant morphology based on a spatial association model, conceptualizes recessive morphology as land functions, land property rights, and land use capitalization, assesses the transition process of land use in mining township. The results showed that the land use transition of mining townships, mainly characterized by changes in land use morphology in mining areas, has begun and will continue for a considerable period. From 2007 to 2022, the degree of spatial association of land use decreased, with a global spatial association measure of 0.6. Regarding dominant morphology, the direct and indirect footprints of coal mining are the leading causes of the change in township land morphology. The area of mining-induced subsidence land increased most significantly (557.94 hm2), and the one-way conversion of farmland to mining-induced subsidence land was the primary mode of this change, accounting for 87.4%. Regarding recessive morphology, the functions of mining-induced subsidence land mainly include economic, ecological, water storage lakes, and photovoltaic water surfaces. Land management rights are interchangeable between farmers, coal mining enterprises, rural collectives, and contractors. The capitalization of comprehensive utilization of coal mining subsidence land creates multiple exclusions in the capital, technology, and transfer identities, further separating the natural connection between farmers and the land. Overall, the land use transition in the mining townships is evident. In the future, local governments across pay sufficient attention and take responsive measures regarding regional food security, farmers' livelihoods, and land management in mining areas. [Display omitted] • Proposing a different overlapping method for analyzing land use/cover change (the model of spatial association). • Clarifying the potential relationship between mining and land use transition (LUT) in townships with high groundwater levels. • Four paths for LUT in the mining township were obtained. • LUT promotes clean production of coal mines and sustainable use of land in mining townships. [ABSTRACT FROM AUTHOR]

• 50 years of data on land subsidence. • Land subsidence smaller for higher ditchwater level. • Subsidence observed to a depth of over 140 cm, and still ongoing after 50 years. • About 30–40 % of subsidence occurs below the lowest phreatic groundwater table. • Consolidation and creep have a large contribution to subsidence, even after 50 years. Peat oxidation in peat meadow areas is causing greenhouse gas emissions as well as land subsidence. Due to yearly fluctuations in soil surface level, long-term monitoring is needed to determine long-term net subsidence rates. In the experimental peat-meadow farm at Zegveld (NL) subsidence platens were installed in 1970 in a field with low ditchwater level, and in 1973 in a field with high ditchwater level. Platens were installed at 7 different depths, allowing to investigate where in the peat profile subsidence occurs. Elevation of platens as well as soil surface has been measured with surveyor's levelling each year at the end of winter, so that a long timeseries up to 2023 is available. Analysis showed that surface level in the field with high ditchwater level subsided by 24 cm in 50 years (4.8 mm/yr), while in the field with low ditchwater level this was 31 cm in 53 years (5.8 mm/yr). Results also indicated that in the field with low ditchwater level, most subsidence due to permanent shrinkage and peat oxidation occurred between 40 and 100 cm depth, while for the other field this was between 0 and 20 and between 40 and 60 cm depth. Finally, in 2023 subsidence was still observed under continuously saturated conditions at 140 cm depth. Presumably, in the aerated part of the profile peat oxidation and the associated earthification process is the main cause of subsidence, while the observed subsidence in the saturated soil at 140 cm depth must be due to other processes, such as consolidation and creep. [ABSTRACT FROM AUTHOR]

The forearc region remains key in understanding the dynamics of convergent plate tectonics. This study focuses on the mechanisms governing tectonic processes within the overriding plate forearc which spans from the trench to the volcanic arc at two key and relatively well studied regions: the Japan Trench and the Middle America Trench offshore SE Costa Rica. We address the questions that have arisen concerning material input into the plate boundary, whether by subduction, accretionary prism formation, or tectonic erosion. In the Japan Trench case study, while tectonic accretion occurs near the trench axis, significant forearc subsidence suggests net material removal, possibly through tectonic erosion that has transferred material to the subducting slab. Debate surrounds the mechanism driving forearc subsidence, with recent studies proposing extensional tectonism as a possible mechanism to exclude subduction erosion. However, seismic evidence challenges this hypothesis, as normal faults indicative of forearc extension are not prominent. Moreover, a quantitative mass-balance analysis fails for the forearc if extensional tectonics rather than tectonic erosion is assumed to have predominantly shaped the margin. The spatio-temporal progression of subsidence across the forearc is further explored; this indicates that peak subduction erosion has occurred beneath the lower slope. The Middle America Trench in SE Costa Rica has also been extensively studied with several drilling expeditions, with particular focus on the area where the aseismic Cocos Ridge is subducting beneath the Caribbean plate. Here the subduction of topographic relief has been traditionally viewed as a process that enhances subduction erosion. Recent studies have challenged this perspective, suggesting instead that subducting topography might lead to net accretion to the margin through various mechanisms. Ocean drilling expeditions provide valuable data on sedimentary successions and forearc tectonic evolution. These drilling data have been not always used to the best of their capacity, which has led to significant discrepancies between drilling-based inferences and seismic interpretations, in particular regarding the presence and nature of unconformities within the forearc sediments. Borehole observations strongly favor the inference that inboard the Cocos Ridge a large amount of subsidence has occurred, linked to recent subduction erosion beneath this forearc. [ABSTRACT FROM AUTHOR]

The evolution of normal fault arrays during rift extension reflects paleo-plate boundary conditions and lithospheric rheology, while controlling seismic hazard and the distribution of basin-hosted resources. Yet, constraining their spatiotemporal development is challenging, particularly where geophysical and subsurface data are absent. Here, we test footwall exhumation modelling using thermochronology as a means of elucidating 4D normal fault array evolution, using the Miocene Central Basin of the Malawi Rift as a natural laboratory. Along-strike trends in exhumational cooling recorded by vertical transects of apatite fission-track and (U–Th)/He data from the basin-bounding Usisya fault scarp reveal a diachronous footwall uplift history that closely reflects 4D trends in hangingwall subsidence recorded by previously published seismic and well data. Initially, pronounced footwall exhumation is restricted to the centres of a series of four isolated normal faults, mirroring the distribution of early syn-rift depocentres. The later onset of footwall exhumation in the intervening areas marks subsequent fault segment propagation and linkage as they formed the through-going Usisya fault system. Elsewhere, cumulative exhumation recorded in the Usisya footwall remains low, coinciding with more significant intra-basinal faulting. This study shows that footwall exhumation modelling constrained by thermochronologic data can reveal the spatiotemporal evolution and strain partitioning within normal fault arrays. • Thermochronology transects along the Usisya fault scarp record footwall exhumation. • Usisya fault evolution is reflected in basin stratigraphy revealed by seismic data. • Malawi rift related cooling along Usisya commenced in the middle Miocene. • Footwall exhumation modelling reveals complex 4D fault exhumation and linkage. [ABSTRACT FROM AUTHOR]

• Analyzes groundwater dynamics and land subsidence in agricultural regions. • Utilizes FFT and STL techniques to identify significant seasonal patterns. • Integrates data from multiple wells for accurate groundwater modeling. • Estimates aquifer parameters using MCMC inversion procedures. • Emphasizes sustainable water management to mitigate subsidence effects. The San Luis Valley (SLV), Colorado, is challenged with implementing sustainable groundwater management in the face of increasing surface water scarcity due to climate change. Groundwater extraction in unconsolidated aquifers such as the SLV can cause cm-scale subsidence and rebound. This study utilizes Interferometric Synthetic Aperture Radar (InSAR) data, validated by Global Navigation Satellite System (GNSS) measurements, to measure subsidence and analyze the groundwater dynamics that cause it. Addressing the challenges of phase decorrelation and data gaps, notably from September 2018 to April 2019, we adopted a modified DS-interpolation algorithm, alongside a Singular Spectrum Analysis (SSA)-based gap filling technique. Furthermore, we enhanced the temporal resolution of groundwater level data through the Theis curve interpolation. These methodologies enabled the integration of observational well data with satellite measurements to calibrate a one-dimensional deformation model, capturing both the elastic and inelastic responses of the aquifer system. Our investigation, spanning 2015 to 2021, reveals both seasonal and long-term subsidence, with the confined aquifer section experiencing up to 1 cm/year of subsidence alongside notable seasonal fluctuations. The methodology presented here provides a path to model subsidence in regions with sparse groundwater level and noisy InSAR data. It also provides valuable insights for developing effective water management strategies in the SLV. [ABSTRACT FROM AUTHOR]

This paper introduces novel semi-analytical models tailored for estimating land subsidence resulting from groundwater extraction in confined aquifers. These models offer high scalability, allowing them to be applied to various well configurations and pumping schedules. Their development involves the numerical integration of two key analytical solutions: the "nucleus of strain" (NoS) (Mindlin and Chen, 1950), which represents a localised zone within the aquifer where a unit change in pore pressure leads to deformation and subsequent surface displacement, and the classic Theis equation (Theis, 1935) for the pore pressure changes induced by a constant-rate well pumping from a laterally unbounded aquifer. These integrations yield surface displacement components, both horizontal and vertical, expressed as functions of two dimensionless spatial–temporal variables, which encompass aquifer depth, thickness, well placement, pumping schedules, and critical hydro-geomechanical parameters like hydraulic conductivity, porosity, vertical compressibility, and water compressibility. Proposed are two distinct modelling approaches: one employing a lookup table (LT) derived from numerical integration results, and the other providing direct closed-form surface displacement solutions by fitting LT data with "hinge models", which use piecewise-linear functions linked by sigmoidal curves for computational efficiency. In both cases, surface displacement components are estimated by plugging in the dimensionless variables. Conditions of variable pumping from multiple wells can be addressed by applying superposition of solutions. In essence, these semi-analytical models offer swift computational capabilities for understanding and forecasting land subsidence dynamics. Their scalability makes them adaptable to a wide array of well configurations and scheduling scenarios, rendering them valuable for numerous applications. They are particularly significant for providing preliminary estimates of the impacts of groundwater development, conducting "what-if" tests, and performing sensitivity analyses to identify key factors affecting land subsidence risk. This underscores the importance of these models in sustainable groundwater resource management and in mitigating land subsidence and its associated consequences. • Innovative frameworks to assess land subsidence from groundwater extraction. • Versatile models adaptable to various pumping well configurations and schedules. • NoS solution integrated into Theis equation for surface displacement calculation. • lookup table (LT) with 2D interpolation and direct solution via hinge model fitting. • Accurate subsidence predictions with errors below 5%, enabling efficient simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigating heavy rainfall and loose fill soil as primary natural triggers for sinkholes in non karst areas. • Identifying metro constructions and pipeline damages as major human-induced factors for urban sinkholes. • The Gray Relation Analysis method was used in sinkhole susceptibility mapping. • Risk assessment based on urban transportation system was conducted for enhanced sinkhole prevention. • A sinkhole risk identification framework employing InSAR and geophysical technologies was proposed. Urban sinkholes can cause subsidence damage to transportation infrastructures, building demolitions and even casualties when they occur suddenly. It is hence essential to identify their forming factors and analyze their spatial distribution features, so as to pave the way for sinkhole risk assessment and mitigation for urban sustainable development. Investigation of urban sinkholes poses a significant challenge because of the multi-factor's confusion, as well as the spatial uncertainties in susceptibility mapping due to urban renewal frequently. To address these issues, a comprehensive urban sinkhole risk assessment framework was proposed, and Shenzhen city in South China was selected as a case study area, where a lot of sinkholes occurred along with intensive human construction activities in recent years. Initially, the sinkhole susceptibility map was drawn using the grey relation analysis (GRA) method, incorporating the spatial information database of meteorology, geology, metro and pipeline systems, and then both the sinkhole density map and the time-varying land subsidence monitoring database were used to verify the accuracy of the sinkhole susceptibility map. Furthermore, the sinkhole risk assessment map in transportation system was subsequently drawn based on the susceptibility map, where the Interferometric Synthetic Aperture Radar (InSAR) and the advanced geophysical exploration technologies were employed to probe the potential sinkholes in critical risk areas. The conclusions reveal that the sinkhole susceptibility map based on GRA method demonstrates a promise in identifying the likelihood of urban sinkholes, and the risk assessment framework can be employed for the prevention and remediation of urban sinkholes, which contributes to an economical and efficient scheme for sinkhole detection, as well as transportation system resilience assessment at a city-wide scale. [ABSTRACT FROM AUTHOR]

[Display omitted] • We explained the tectonic evolution of the Eastern Subbasin since the Late Cretaceous that marks the eastern margin of the Northern South Yellow Sea Basin. • The evolution of the subbasin includes not only subsidence (rapid, slow, accelerated, and gradual) but short-term uplift. • The subbasin evolved with sequential development of nested duplex structures created by dextral extension. • The NW subduction of the Pacific Plate oblique to the NE Asian margin played an important role by inducing SE extension at the margin and NE-SW transtensional dextral slip parallel to the margin. The South Yellow Sea Basin is the largest sedimentary basin in the Yellow Sea. The Gunsan Basin in the central eastern part of the Northern South Yellow Sea Basin comprises the Western, Central, and Eastern Subbasins. The Eastern Subbasin marks the eastern margin of the South Yellow Sea Basin. Interpretation of multi-channel seismic profiles and balanced cross-section restoration of depth-converted seismic profiles reveal the structural characteristics and evolution of the Eastern Subbasin. The subbasin comprises three groups of faults: NW-SE, NE-SW, and NNE-SSW trending faults. The subsidence pattern of the subbasin, derived from the cross-section restoration analysis, indicates five distinguished evolution phases: (i) rapid subsidence in the Late Cretaceous, (ii) slow subsidence from the Paleocene to the Eocene, (iii) accelerated subsidence in the Oligocene, (iv) alternation of the uplift and subsidence in the Early Miocene, and (v) gradual subsidence since the Middle Miocene. The main and moderate subsidence can be explained by the combination of extension in the SE and NE-SW directions that formed double duplex structures. We suggest that the NW oblique subduction of the Pacific Plate under the NE Asia margin induced both extension toward the trench and dextral strike-slip parallel to the margin. The extension toward the trench caused SE transtension in a local pull-apart setting, whereas the dextral strike-slip parallel to the margin caused NE-SW extension, inducing more significant subsidence. The combined processes resulted in the progressive development of nested duplex structures. The evolution of the Eastern Subbasin is not compatible with previously suggested models for the western part of the South Yellow Sea Basin including foreland basin formation and transtension induced by branch faults of the Tan-Lu Fault. [ABSTRACT FROM AUTHOR]

Drainage network systems are responsive elements to recent active tectonics from among all the topographic features. In geodynamically active areas, fluvial landscapes can record different processes through the formation and current presence of features related to spatial-temporal variation in base-level fall and vertical incision of stream channels. This study focuses on the tectonic evolution of the Alessandria Basin, a synorogenic tectonic basin located at the junction between the Alps and the Apennines, that experienced progressive subsidence during the overthrusting of the Monferrato Thrust Front (the westernmost outer arc of the Apennine belt) onto the Po Foreland Basin. Even though several studies have assessed the Neogene tectonic evolution at a regional scale, rates and timing of the Quaternary activity are still poorly understood in terms of both Alps/Apennines uplift and activity of the compressive front of the Monferrato Arc. In this paper, we applied the method of the river profile linear inversions to reconstruct the base-level fall history of 6 catchments that drain into the Alessandria Basin. We used nine 10Be-derived basin-average denudation rates to constrain the erodibility parameter needed to infer base-level fall rates from χ-transformed river profiles. The results describe the tectonic history of the area in the last ∼5 Ma, documenting increases in base-level fall rate with an initial peak between 3 and 2.5 Ma, and a second between 2 and 1.5 Ma. While the first peak is coeval with the uplift phase that involved most of the northern-central Apennine, the second one suggests an acceleration in subsidence of the Alessandria Basin concurrently with the uplift of the Monferrato Thrust Front. [ABSTRACT FROM AUTHOR]

The study focuses on urban damage and surface deformation in the Kathmandu city region that occurred due to the massive earthquake in Nepal in 2015. The deformation was estimated from pre-and post-earthquake C-band Sentinel-1A synthetic aperture radar (SAR) satellite images employing the Interferometric SAR (InSAR) technique. The study highlighted a latitudinal pattern in deformation from the north to south directions, most likely directed by the structural alignments (ridges and valleys) in the Himalayan region. The city-scale study exhibited an increase in the intensity of displacement from the north (<-5cm) to the south (>-20 cm) direction in Kathmandu city. Major parts of the city observed moderate subsidence (-10 cm to −15 cm), while the south-eastern and central parts observed severe subsidence (>15 cm) due to structural damage and collapse of buildings. The incidences of land subsidence and damage to buildings were recorded in the entire Kathmandu Municipal Corporation (KMC) area - a large part (86%; 43.84 km2) of which was built-up land and inhabited population (49% of 1,744,240 people) in 2015 - affecting built structures, transport networks, and world heritage monuments. The earthquake hazard-risk analysis demonstrated that the built-up land in the south-eastern and north-western parts were the severely affected areas due to high population and high built-up density. The study elucidates the potential application of InSAR technology using freely available concurrent Sentinel-1A SAR data in the estimation of earthquake induced damage study at urban scale and hazard-risk assessment that aid in the formulation of an effective disaster risk reduction policy framework for the region. [ABSTRACT FROM AUTHOR]

Population growth and increased agricultural activities in Karaman and its surrounding region, located in the southwest of the Konya Closed Basin, have led to increasing water demand in recent years. Karaman's drinking and irrigation water needs are also almost entirely met from groundwater. Accordingly, excessive groundwater extraction deepens the water level inside the aquifers, resulting in land subsidence. In this study, the spatio-temporal evolution of surface deformation in and around the city of Karaman was investigated using Sentinel-1/A SAR data, Global Navigation Satellite System (GNSS), and groundwater levels over a period from 2016 to 2021. Sentinel-1 images obtained from ascending satellite orbits were evaluated using the persistent scatter interferometry (PS-InSAR) approach. Mean velocity maps and line-of-sight displacement time series were obtained and compared with GNSS data and groundwater levels. In all three datasets, a significant level of subsidence was obtained in the study region. The land subsidence values were found to be 25 mm/yr in the city center of Karaman and reached values of 50 mm/yr toward the northern part of the province. According to the results, there is a strong correlation between subsidence rates and groundwater levels over the analyzed period, indicating that subsidence in the area is most likely driven by excessive groundwater withdrawal. [ABSTRACT FROM AUTHOR]

Due to the lack of an additional anterior plate, the motion stability of a zero-profile device with an anchored cage (AC) may be inferior to that of a traditional plate-cage construct (PCC). However, the impact of this difference in motion stability on various outcomes has not been fully explored. Therefore, the aim of this study was to compare the motion stabilization features of an AC and a PCC and analyze their impact on postoperative outcomes and complications. A retrospective study of patients treated with single-level anterior cervical discectomy and fusion from January 2008 to May 2016 was performed. First, clinical and radiological outcomes, postoperative complications and time to achieve motion stabilization were compared between the AC and PCC groups. Then, based on the time to achieve motion stabilization, all patients were divided into group A (time to achieve motion stabilization <3 months), group B (time to achieve motion stabilization from 3–6 months), and group C (time to achieve motion stabilization >6 months). The early postoperative complications were compared across the 3 groups. Motion stabilization was measured on dynamic cervical radiographs using the interspinous process method and Cobb angle method according to previously published methods. A total of 160 patients met the inclusion criteria, including 90 patients in the AC group and 70 patients in the PCC group. There were no significant differences between the AC and PCC groups in the clinical outcomes, C2–7 angle change, segmental angle change, final fusion rate or adjacent-level degeneration (P > 0.05). The disc height loss was 2.26 ± 1.00 mm in the AC group and 1.76 ± 1.13 mm in the PCC group (P = 0.004), and the incidence of implant subsidence was 24.44% in the AC group and 11.43% in the PCC group (P = 0.036). In addition, the PCC was more dynamically stable than the AC at 3 months post-surgery (P < 0.001), and at this time, the disc height loss and implant subsidence in motion-stable patients were significantly lower than those in motion-unstable patients (P < 0.05). Furthermore, our results also showed that when the arrival time of motion stabilization was prolonged, the loss of disc height and occurrence of subsidence gradually increased. More attention should be given to minimizing the adverse impact of poor motion stability in the design and development of future zero-profile cervical implants, although this has little impact on clinical efficacy. [ABSTRACT FROM AUTHOR]