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Passive seismic datasets are a key technology for exploration and monitoring of subsurface reservoirs. Searching for alternative resources in the framework of the energy transition creates a surge for identifying as many potential sites as possible suitable for geothermal exploitation. The Lower Rhine Embayment, at the western border of North Rhine-Westphalia in Germany, is an extensional system with a very high potential for geothermal exploitation. The area experiences moderate but continuous natural seismicity. Here, we report on a passive seismic dataset recorded with 48 seismic stations centred at and around Eschweiler-Weisweiler. Background seismic noise levels are high at this site due to high levels of anthropogenic noise and thick unconsolidated sedimentary layers. The final station layout is a compromise between targeted network design and suitably quiet locations. We show that the network design allows the application of state-of-the-art methods including waveform-based source location methods and ambient noise velocity imaging methods. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing (HF) operations are widely associated with induced seismicity in the Western Canadian Sedimentary Basin. This study correlates injection parameters of 12,903 HF stages in the Kiskatinaw area in northeast British Columbia with an enhanced catalog containing 40,046 earthquakes using a supervised machine learning approach. It identifies relevant combinations of geological and operational parameters related to individual HF stages in efforts to decipher fault activation mechanisms. Our results suggest that stages targeting specific geological units (here, the Lower Montney formation) are more likely to induce an earthquake. Additional parameters positively correlated with earthquake likelihood include target formation thickness, injection volume, and completion date. Furthermore, the COVID‐19 lockdown may have reduced the potential cumulative effect of HF operations. Our results demonstrate the value of machine learning approaches for implementation as guidance tools that help facilitate safe development of unconventional energy technologies. Plain Language Summary: Hydraulic fracturing (HF), a technique used in unconventional energy production, increases rock permeability to enhance fluid movement. Its use has led to an unprecedented increase of associated earthquakes in the Western Canadian Sedimentary Basin in the last decade, among other regions. Numerous studies have investigated the relationship between induced earthquakes and HF operations, but the connection between specific geological and operational parameters and earthquake occurrence is only partly understood. Here, we use a supervised machine learning approach with publicly available injection data from the British Columbia Oil and Gas Commission to identify influential HF parameters for increasing the likelihood of a specific operation inducing an earthquake. We find that geological parameters, such as the target formation and its thickness, are most influential. A small number of operational parameters are also important, such as the injected fluid volume and the operation date. Our findings demonstrate an approach with the potential to develop tools to help enable the continued development of alternative energy technology. They also emphasize the need for public access to operational data to estimate and reduce the hazard and associated risk of induced seismicity. Key Points: We use supervised machine learning to investigate the relationship between hydraulic fracturing operation parameters and induced seismicityGeological properties and a limited number of operational parameters predominantly influence the probability of an induced earthquakeThe approach has the potential to guide detailed investigations of injection parameters critical for inducing earthquakes [ABSTRACT FROM AUTHOR]

Earthquakes resulting from hydraulic fracturing (HF) can have delayed triggering relative to injection commencement over a varied range of time scales, with the majority of M ≥ 4 mainshocks occurring near/after well completion. This poses serious challenges for risk mitigation and hazard assessment. Here, we document a high‐resolution, three‐dimensional source migration process with delayed mainshock triggering that is controlled by local hydrogeological conditions near Fox Creek, Alberta, Canada. Our results reveal that poroelastic effects might contribute to induced seismicity, but are probably insufficient to activate a large fault segment not critically stressed. The rapid pore‐pressure build‐up from HF can be very localized and capable of producing large, felt earthquakes if adequate hydrological paths exist. We interpret the delayed triggering as a manifestation of pore‐pressure build‐up along pre‐existing faults needed to facilitate seismic failure. Our findings can explain why so few injection operations are seismogenic. Plain Language Summary: Fluid injection‐induced earthquakes (IIE), especially those M ≥ 4 mainshocks, are often observed to occur near or after well completion. Such delayed triggering relative to injection commencement poses serious challenges for both regulators and the energy industry to establish an effective mitigation strategy for the potential seismic risk. In this study, we reveal a high‐resolution, complex three‐dimensional pattern of IIE migration near Fox Creek, Alberta, Canada. The observed first‐outward‐then‐inward IIE sequence highlights the significance of hydrogeological networks in facilitating fluid pressure migration and the associated seismic failure. The detailed spatiotemporal distribution of IIE suggests that the effect of pore‐pressure build‐up from hydraulic fracturing (HF) can be very localized. The delayed triggering is a combined result of the fluid pressure migration and the current stress state of the hosting fault system away from the HF wells. The findings from this study also provide plausible explanations on why only a very limited number of fluid injections are seismogenic. Key Points: We document a complex 3D source migration process with delayed mainshock triggering that is controlled by a local hydrogeological settingPoroelastic effects contribute to induced events but are probably insufficient to activate a large fault segment not critically stressedRapid pore‐pressure build‐up can be very localized and lead to large earthquakes if adequate hydrological paths exist [ABSTRACT FROM AUTHOR]

Utilizing surveillance data from five sites participating in the Autism and Developmental Disabilities Monitoring Network, we investigated contributions of surveillance subject and census tract population sociodemographic characteristics on variation in autism spectrum disorder ascertainment and prevalence estimates from 2000 to 2008 using ordinal hierarchical models for 2489 tracts. Multivariable analyses showed a significant increase in ascertainment of autism spectrum disorder cases through both school and health sources, the optimal ascertainment scenario, for cases with college-educated mothers (adjusted odds ratio = 1.06, 95% confidence interval = 1.02-1.09). Results from our examination of sociodemographic factors of tract populations from which cases were drawn also showed that after controlling for other covariates, statistical significance remained for associations between optimal ascertainment and percentage of Hispanic residents (adjusted odds ratio = 0.93, 95% confidence interval = 0.88-0.99) and percentage of residents with at least a bachelor's degree (adjusted odds ratio = 1.06, 95% confidence interval = I.01 -- I.II). We identified sociodemographic factors associated with autism spectrum disorder prevalence estimates including race, ethnicity, education, and income. Determining which specific factors influence disparities is complicated; however, it appears that even in the presence of education, racial and ethnic disparities are still apparent. These results suggest disparities in access to autism spectrum disorder assessments and special education for autism spectrum disorder among ethnic groups may impact subsequent surveillance. [ABSTRACT FROM AUTHOR]

Aseismic slip loading has recently been proposed as a complementary mechanism to induce moderate-sized earthquakes located within a few kilometers of the wellbore over the timescales of hydraulic stimulation. However, aseismic slip signals linked to injection-induced earthquakes remain largely undocumented to date. Here we report a new type of earthquake characterized by hybrid-frequency waveforms (EHWs). Distinguishing features from typical induced earthquakes include broader P and S-pulses and relatively lower-frequency coda content. Both features may be causally related to lower corner frequencies, implying longer source durations, thus, either slower rupture speeds, lower stress drop values, or a combination of both. The source characteristics of EHWs are identical to those of low-frequency earthquakes widely documented in plate boundary fault transition zones. The distribution of EHWs further suggests a possible role of aseismic slip in fault loading. EHWs could thus represent the manifestation of slow rupture transitioning from aseismic to seismic slip., (© 2021. Crown.)

Background: Children with intellectual disability (ID), characterized by impairments in intellectual functioning and adaptive behavior, benefit from early identification and access to services. Previous U.S. estimates used administrative data or parent report with limited information for demographic subgroups., Objective: Using empiric measures we examined ID characteristics among 8-year-old children and estimated prevalence by sex, race/ethnicity, geographic area and socioeconomic status (SES) area indicators., Methods: We analyzed data for 8-year-old children in 9 geographic areas participating in the 2014 Autism and Developmental Disabilities Monitoring Network. Children with ID were identified through record review of IQ test data. Census and American Community Survey data were used to estimate the denominator., Results: Overall, 11.8 per 1,000 (1.2%) had ID (IQ ≤ 70), of whom 39% (n = 998) also had autism spectrum disorder. Among children with ID, 1,823 had adaptive behavior test scores for which 64% were characterized as impaired. ID prevalence per 1,000 was 15.8 (95% confidence interval [95% CI], 15.0-16.5) among males and 7.7 (95% CI, 7.2-8.2) among females. ID prevalence was 17.7 (95% CI, 16.6-18.9) among children who were non-Hispanic black; 12.0 (95% CI, 11.1-13.0), among Hispanic; 8.6 (95% CI, 7.1-10.4), among non-Hispanic Asian; and 8.0 (95% CI, 7.5-8.6), among non-Hispanic white. Prevalence varied across geographic areas and was inversely associated with SES., Conclusions: ID prevalence varied substantively among racial, ethnic, geographic, and SES groups. Results can inform strategies to enhance identification and improve access to services particularly for children who are minorities or living in areas with lower SES., Competing Interests: Declaration of competing interest The authors have no potential conflicts of interest to disclose., (Published by Elsevier Inc.)

Objective: Mothers of advanced maternal age (AMA) at childbirth (age ≥35 years) may have different perceptions of autism spectrum disorder (ASD) risk, independent of sociodemographic factors, that may affect ASD identification. We aimed to estimate associations between AMA and both age of a child's first evaluation noting developmental concerns and time from first evaluation to first ASD diagnosis., Methods: We used data for 8-year-olds identified with ASD in the 2008 to 2012 Autism and Developmental Disabilities Monitoring Network. We estimated differences in age at first evaluation noting developmental concerns and time to first ASD diagnosis by AMA using quantile and Cox regression., Results: Of 10,358 children with ASD, 19.7% had mothers of AMA. AMA was associated with higher educational attainment and previous live births compared with younger mothers. In unadjusted analyses, AMA was associated with earlier first evaluation noting developmental concerns (median 37 vs 40 mo) and patterns in time to first evaluation (hazard ratio: 1.12, 95% confidence interval: 1.06-1.18). Associations between AMA and evaluation timing diminished and were no longer significant after adjustment for socioeconomic and demographic characteristics. Children's intellectual disability did not modify associations between AMA and timing of evaluations., Conclusion: Advanced maternal age is a sociodemographic factor associated with younger age of first evaluation noting developmental concerns in children with ASD, but AMA was not independently associated likely, because it is a consequence or cofactor of maternal education and other sociodemographic characteristics. AMA may be a demographic factor to consider when aiming to screen and evaluate children at risk for ASD.

The Social Communication Questionnaire is one of the most commonly used screening tools for autism spectrum disorder. The Social Communication Questionnaire is a caregiver-reported questionnaire with 40 items based on questions from the Autism Diagnostic Interview-Revised. This study collected Social Communication Questionnaire data from a community-based, multi-stage case identification design epidemiologic study in one socioeconomically disadvantaged county in Taiwan. The Social Communication Questionnaire was distributed to 3034 school children, aged 6-8 years. Item prevalence results indicate males were reported to have more autism-related behaviors than females (higher prevalence on most items), in the whole study sample as well as in children meeting Social Communication Questionnaire clinical cut-offs (⩾15). Children whose biological fathers completed the Social Communication Questionnaire were reported to have more behavioral issues than children whose biological mothers were the respondent. Lower respondent education levels were associated with reports of clinically concerning autism-related behaviors. However, males were not at higher risk of meeting Social Communication Questionnaire clinical cut-offs than females in this study population. Findings from this study help to better understand reporting patterns on children's autism-related behaviors potentially due to social demographic characteristics and child sex, which may lead to improved identification of these behaviors.

Lead, mercury, and arsenic are neurotoxicants with known effects on neurodevelopment. Autism spectrum disorder (ASD) is a neurodevelopmental disorder apparent by early childhood. Using data on 4486 children with ASD residing in 2489 census tracts in five sites of the Centers for Disease Control and Prevention's Autism and Developmental Disabilities Monitoring (ADDM) Network, we used multi-level negative binomial models to investigate if ambient lead, mercury, and arsenic concentrations, as measured by the US Environmental Protection Agency National-Scale Air Toxics Assessment (EPA-NATA), were associated with ASD prevalence. In unadjusted analyses, ambient metal concentrations were negatively associated with ASD prevalence. After adjusting for confounding factors, tracts with air concentrations of lead in the highest quartile had significantly higher ASD prevalence than tracts with lead concentrations in the lowest quartile (prevalence ratio (PR) = 1.36; 95 '% CI: 1.18, 1.57). In addition, tracts with mercury concentrations above the 75th percentile (>1.7 ng/m(3)) and arsenic concentrations below the 75th percentile (≤0.13 ng/m(3)) had a significantly higher ASD prevalence (adjusted RR = 1.20; 95 % CI: 1.03, 1.40) compared to tracts with arsenic, lead, and mercury concentrations below the 75th percentile. Our results suggest a possible association between ambient lead concentrations and ASD prevalence and demonstrate that exposure to multiple metals may have synergistic effects on ASD prevalence.

Objective: To examine associations between prenatal use of selective serotonin reuptake inhibitors (SSRIs) and the odds of autism spectrum disorders (ASDs) and other developmental delays (DDs)., Methods: A total of 966 mother-child pairs were evaluated (492 ASD, 154 DD, 320 typical development [TD]) from the Childhood Autism Risks from Genetics and the Environment (CHARGE) Study, a population-based case-control study. Standardized measures confirmed developmental status. Interviews with biological mothers ascertained prenatal SSRI use, maternal mental health history, and sociodemographic information., Results: Overall, prevalence of prenatal SSRI exposure was lowest in TD children (3.4%) but did not differ significantly from ASD (5.9%) or DD (5.2%) children. Among boys, prenatal SSRI exposure was nearly 3 times as likely in children with ASD relative to TD (adjusted odds ratio [OR]: 2.91; 95% confidence interval [CI]: 1.07-7.93); the strongest association occurred with first-trimester exposure (OR: 3.22; 95% CI: 1.17-8.84). Exposure was also elevated among boys with DD (OR: 3.39; 95% CI: 0.98-11.75) and was strongest in the third trimester (OR: 4.98; 95% CI: 1.20-20.62). Findings were similar among mothers with an anxiety or mood disorder history., Conclusions: In boys, prenatal exposure to SSRIs may increase susceptibility to ASD or DD. Findings from published studies on SSRIs and ASD continues to be inconsistent. Potential recall bias and residual confounding by indication are concerns. Larger samples are needed to replicate DD results. Because maternal depression itself carries risks for the fetus, the benefits of prenatal SSRI use should be carefully weighed against potential harms., (Copyright © 2014 by the American Academy of Pediatrics.)

Past research has shown that children with autism and their families have compromised quality of life (QOL) in several domains. This study examined QOL and parental concerns in children with autism during early childhood, childhood, and adolescence compared to children with Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder (ADD/ADHD) and to typical controls from a US national sample. Families with children diagnosed with autism reported more profound QOL effects than families of children with ADD/ADHD or unaffected controls. Children with autism were significantly less likely to attend religious services, more likely to miss school, and less likely to participate in organized activities. Parental concerns over learning difficulty, being bullied, stress-coping, and achievement were overwhelming in the autism group relative to the comparison groups.

The objective of this study was to examine injury risk in children with autism, ADD/ADHD, learning disability, psychopathology, or other medical conditions. Children aged 3-5 years who participated in the National Survey of Children's Health were included. Six study groups were analyzed in this report: autism (n=82), ADD/ADHD (n=191), learning disability (n=307), psychopathology (n=210), other medical conditions (n=1802), and unaffected controls (n=13,398). The weighted prevalence of injury in each group was 24.2% (autism), 26.5% (ADD/ADHD), 9.3% (learning disability), 20.5% (psychopathology), 14.6% (other medical conditions), and 11.9% (unaffected controls). Compared to unaffected controls, the risk of injury was 2.15 (95% confidence interval (CI): 1.00-4.60), 2.74 (95% CI: 1.63-4.59), 2.06 (95% CI: 1.24-3.42), and 1.26 (95% CI: 1.00-1.58) in children with autism, ADD/ADHD, psychopathology, and other medical conditions, respectively, after adjusting for child sex, child age, number of children in the household, child race, and family poverty level. Children with autism, ADD/ADHD, and other psychopathology were about 2-3 times more likely to experience an injury that needs medical attention than unaffected controls. Future studies need to clarify the extent to which injuries in young children with autism, ADD/ADHD, and psychopathology are related to core symptoms, comorbid conditions, associated behaviors, or unintentional injuries due to lack of additional supervision from caregivers.