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Scanning Electron Microscopy (SEM) is used for source rock characterization to understand rock texture and compositional variations, porosity, and pore sizes. However, despite having significant benefits to characterization, obtaining quantitative results by SEM is time consuming and costly, and therefore the number of images collected per well is generally limited. Recent advances in image processing make obtaining quantitative data from images more accessible. This improves our ability to gather more image-based data on multiple wells for integration with larger scale measurements. Carbonate rich source rocks were sampled from several wells for SEM imaging. Large field-of-view SEM images were collected and segmented using supervised machine learning to label the pores, fractures/cracks, organics, high density minerals, and matrix minerals. Post-processing methods were used to correct mislabeled components. The relative amount of organic-contained porosity to total porosity (R1) and the relative amount of organic content to total porosity (R2) were calculated for each sample. Porosity was also obtained from crushed rock samples using the Gas Research Institute method. Pyrolysis was used to determine the productivity index and residual hydrocarbon content. Total porosity and organic content are two properties that are used to indicate rock quality. The results show that the R1 and R2 ratios from quantitative image-based analyses can be used to indicate potentially better quality. When compared across several wells of similar maturity, these quality metrics can be used to highlight wells with potentially better quality that warrant additional characterization. Finally, by comparing image-based data to that measured at larger scales, thermal maturity indicators can also be provided. This paper presents a method using image-based characterization to provide relative comparisons of reservoir quality between wells and a method to combine image-based and crushed rock analyses to compare source rock maturity. The results and workflow presented impact special core analysis for unconventional reservoirs and reservoir quality assessment and can complement characterization obtained by other methods.

International audience; Background and objectives The fact that metabolism and immune function are regulated by an endogenous molecular clock that generates circadian rhythms suggests that the magnitude of ischemia reperfusion, and subsequent inflammation on kidney transplantation, could be affected by the time of the day. Design, setting, participants, & measurements We evaluated 5026 individuals who received their first kidney transplant from deceased heart-beating donors. In a cause-specific multivariable analysis, we compared delayed graft function and graft survival according to the time of kidney clamping and declamping. Participants were divided into those clamped between midnight and noon ( ante meridiem [ am ] clamping group; 65%) or clamped between noon and midnight ( post meridiem [ pm ] clamping group; 35%), and, similarly, those who underwent am declamping (25%) or pm declamping (75%). Results Delayed graft function occurred among 550 participants (27%) with am clamping and 339 (34%) with pm clamping (adjusted odds ratio, 0.81; 95% confidence interval, 0.67 to 0.98; P =0.03). No significant association was observed between clamping time and overall death-censored graft survival (hazard ratio, 0.92; 95% confidence interval, 0.77 to 1.10; P =0.37). No significant association of declamping time with delayed graft function or graft survival was observed. Conclusions Clamping between midnight and noon was associated with a lower incidence of delayed graft function, whereas declamping time was not associated with kidney graft outcomes.

Summary Background Scientific societies recommend to seek cancer prior to bariatric surgery. In our tertiary referral center, we aimed to study performance of abdominal CT-scan before bariatric surgery. Patients and methods We retrospectively included all patients who underwent bariatric surgery and a pre-operative abdominal CT-scan in our academic center, between January 2015 and December 2018. Results We included 521 patients (417 women and 104 men) with a mean age of 48.0 ± 11.5 years. Mean preoperative body mass index was 44.9 ± 7.0 kg/m2. Among the 392 patients with abnormal CT-scan, mean number of anomalies per patient was of 2.2 ± 1.2. Vast majority of anomalies (91.8%) were non-significant. Only 5 (1%) patients needed treatment prior to bariatric surgery. No factor predictive of abnormal CT-scan was found. Conclusion Only few patients had severe anomaly on CT-scan before bariatric surgery. Abdominal CT-scan could not be advocated to seek cancer before bariatric surgery.

Resume Introduction Il est recommande par les principales societes scientifiques de rechercher un cancer chez les patients avant chirurgie bariatrique. Dans notre centre universitaire, nous avons voulu etudier l’interet de realiser un scanner abdominal avant chirurgie bariatrique. Patients et methodes Nous avons inclus retrospectivement tous les patients ayant eu une chirurgie bariatrique avec un scanner abdominal pre-operatoire dans notre centre entre janvier 2015 et decembre 2018. Resultats Nous avons inclus 521 patients (417 femmes et 104 hommes) avec une moyenne d’âge de 48,0 ± 11,5 ans. L’indice de masse corporelle moyen en preoperatoire etait de 44,9 ± 7,0 kg/m2. Parmi les 392 patients avec un scanner anormal, le nombre moyen d’anomalies par patient etait de 2,2 ± 1,2. La grande majorite (91,8 %) des anomalies etaient non significatives. Seulement 5 (1 %) des patients ont eu besoin d’un traitement de leur anomalie en preoperatoire. Aucun facteur de risque de developper des anomalies sur le scanner n’a ete retrouve. Conclusion Peu de patients avaient une anomalie severe sur le scanner abdominal avant chirurgie bariatrique. Le scanner abdominal n’est donc pas a recommander en pre-operatoire chez ces patients.

The timing of food intake throughout the day can alter circadian clocks and metabolism to modulate the course of obesity. We conducted a systematic literature review to determine whether the timing of meals could alter the change in body weight after bariatric surgery in adults. Twelve cohort studies examined the association between meal timing and changes in body weight after bariatric surgery. Eight studies suggested an association between meal timing and weight loss. All studies examined simple exposure variables such as frequency of breakfast or dinner consumption and overnight meals. Overall, the low-quality evidence that food consumption at the end of the day is associated with lower weight loss after bariatric surgery in adults warrants further research.

The thermogenic transformation of kerogen into hydrocarbons accompanies the development of a pore network within the kerogen that serves as gas storage locations both in pore space and the surface ...

Sleeve gastrectomy (SG) is the most commonly performed bariatric surgical procedure worldwide. However, the impact of SG on Barrett’s esophagus (BE) remains unknown. The main objective was to determine the rate of BE 5 years after SG. Patients, operated in 2012 by SG in one center, who preoperatively and postoperatively (5 years) underwent upper gastrointestinal endoscopy (UGIE), 24-h pH monitoring, and esophageal manometry, were included. A total of 59 (81.4% of females) patients were included. Preoperative mean age and body mass index were 45.2 ± 11.7 years and 45.2 ± 8.1 kg/m2 respectively. Preoperative 24-h pH monitoring reported gastroesophageal reflux disease (GERD) in 18 (30.5%) patients. The mean total body weight loss at 5 years was 16.1 ± 11.2%. No significant difference was observed between preoperative and postoperative de Meester’s score (20.2 ± 27.1 and 21.0 ± 21.5 respectively (p = 0.91)) nor between preoperative and postoperative number of acid reflux episodes per 24 h (65.1 ±

Background Arterial stiffness (AS) is an independent predictor of cardiovascular risk, and could be used as a surrogate marker of improvement in cardiovascular risk following bariatric surgery. The aim of this study was to compare AS before and after surgery. Methods One hundred and thirty-four patients undergoing bariatric surgery between May 2016 and January 2019 were prospectively included. AS was measured on pulse wave velocity (PWV) with the pOpmetre® device pre- and postoperatively. The main endpoint was change in PWV between baseline and 3 months post-surgery. Results Overall, mean PWV was 6.87 m/s preoperatively and 6.71 m/s at 3 months (P = 0.7148). Patients with pathologic PWV (> 2 standard deviations from expected value for age) showed significant improvement at 3 months (31 patients; 10.1 m/s preoperatively vs 7.5 m/s at 3 months; P = 0.007). These results did not correlate with improvement in other clinical or biological parameters following surgery (excess weight loss, mean blood pressure, fasting blood glucose, waist circumference, body composition). Conclusion These results suggest that pathological arterial stiffness may resolve following bariatric surgery independently of the other factors influencing cardiovascular risk in obesity.

Heterogeneity of interindividual and intraindividual responses to interventions is often observed in randomized, controlled trials for obesity. To address the global epidemic of obesity and move toward more personalized treatment regimens, the global research community must come together to identify factors that may drive these heterogeneous responses to interventions. This project, called OBEDIS (OBEsity Diverse Interventions Sharing - focusing on dietary and other interventions), provides a set of European guidelines for a minimal set of variables to include in future clinical trials on obesity, regardless of the specific endpoints. Broad adoption of these guidelines will enable researchers to harmonize and merge data from multiple intervention studies, allowing stratification of patients according to precise phenotyping criteria which are measured using standardized methods. In this way, studies across Europe may be pooled for better prediction of individuals' responses to an intervention for obesity - ultimately leading to better patient care and improved obesity outcomes. © 2020 The Author(s) Published by S. Karger AG, Basel.

Summary Rock strength is seldom considered important by the hydrocarbon industry to help monitor the drilling progress, evaluate wellbore stability, guide well completions, or predict the success of hydraulic fracturing in unconventional reservoirs. With respect to hydraulic fracturing, rock-elastic moduli are routinely used to evaluate stress anisotropy. However, rock strength may also be a crucial parameter to evaluate when designing hydraulic-fracturing strategies to stimulate production from the rock volume. However, because of the density of horizontal laminae comprising the rock structure within a vertical whole core, the true geomechanical anisotropy for both properties is difficult to measure from extracted core plugs. Often, core-plug drilling and extraction techniques do not produce intact core plugs to measure these parameters consistently because of the laminated rock fabric. The integrity of the rock makes it is difficult to interpret both elastic moduli and rock-strength measurements using the recovered plugs extracted from horizontal, vertical, and diagonal azimuths. To address that challenge, a new, nondestructive method is demonstrated in which rebound-hardness measurements taken across a specifically gridded, slabbed rock surface can provide an estimate of the rock strength. The collected rebound-hardness numbers (RHNs) are converted into unconfined-compressive strengths (UCSs) using an empirical algorithm. The empirical algorithm was developed using UCSs measured from core plugs correlated to RHNs measured from the face of those same core plugs. The derived UCSs are then used to represent the source rock's mechanical characteristics, which can be presented as a contour map across the surface. These results have been correlated to the mineralogy of the rock surface, quantified, and mapped using micro-X-ray-fluorescence (µ-XRF) elemental maps. Differences in UCS can then be correlated to the changing mineral content of the rock surface. This nondestructive estimation of rock strength was conducted to address the challenge of relating core-scale measurements to reservoir-scaled analysis to improve hydraulic-fracturing designs in unconventional source rocks.

Oil and gas production from shale formations has proven to be economical because of advances in hydraulic fracturing but remains very challenging in part because of the presence of the ductile, polymer nature of the hydrocarbon source material, kerogen. This organic matter is intertwined among silicates, aluminosilicates, and other minerals as fine laminae that weave among the shale rock fabric, adding soft mechanical cohesion to the material. A potential solution has been developed, a new type of reactive fracturing fluid composed of strong oxidizers such as bromate (BrO3–), which could mitigate the adverse effects of the polymeric nature of kerogen on the hydraulic conductivity of the fractured shale formation. High-resolution scanning electron microscopy of kerogen-rich shale samples before and after fluid treatment demonstrates notable porosity enhancement evident by cracks forming in the macerals and augmenting the volumetric porosity. The stability of the reactive components at elevated reservoir te...

Mitophagy and mitochondrial integrated stress response (ISR) are 2 primary protective mechanisms to maintain functional mitochondria. Whether these 2 processes are coordinately regulated remains unclear. Here we show that mitochondrial fission 1 protein (Fis1), which is required for completion of mitophagy, serves as a signaling hub linking mitophagy and ISR. In mouse hepatocytes, high fat diet (HFD) feeding induces unresolved oxidative stress, defective mitophagy and enhanced type I interferon (IFN-I) response implicated in promoting metabolic inflammation. Adenoviral-mediated acute hepatic Fis1 overexpression is sufficient to reduce oxidative damage and improve glucose homeostasis in HFD-fed mice. RNA-Seq analysis reveals that Fis1 triggers a retrograde mitochondria-to-nucleus communication upregulating ISR genes encoding anti-oxidant defense, redox homeostasis, and proteostasis pathways. Fis1-mediated ISR also suppresses expression of IFN-I-stimulated genes through activating transcription factor 5 (Atf5), which inhibits the transactivation activity of interferon regulatory factor 3 (Irf3) known to control IFN-I production. Metabolite analysis demonstrates that Fis1 activation leads to accumulation of fumarate, a TCA cycle intermediate capable of increasing Atf5 activity. Consequently, hepatic Atf5 overexpression or monomethyl fumarate (MMF) treatment improves glucose homeostasis in HFD-fed mice. Collectively, these results support the potential use of small molecules targeting the Fis1-Atf5 axis, such as MMF, to treat metabolic diseases.

Microwave measurements of slabbed, whole core surfaces from calcite-rich shales are correlated to mineralogy quantified from elemental maps measured using micro X-ray Fluorescence (µXRF) across those same surfaces. The nondestructive microwave measurements were performed using a spot-probe reflectometer antenna with a 30 mm-diameter illumination area using frequencies between 2.5 and 20 GHz. The broadband dielectric results show a strong correlation between the dielectric constant and the kerogen/pyrite content in the calcite-dominated intervals where different types of organic and/or pyrite inclusions are easily identified. This novel non-destructive method of analysis can measure the dielectric effects caused by mineral substrates that influence borehole resistivity measurements. These effects often cause erroneous computation of water and hydrocarbon saturations in unconventional reservoirs.

Sleeve gastrectomy is the most commonly performed bariatric surgery these days but is associated with de novo reflux. We aimed to study the influence of hypotonic lower esophageal sphincter (LES) on postoperative gastroesophageal reflux disease (GERD). Patients with pre- and postoperative esophageal high-resolution manometry (HRM) and 24-h pH monitoring (pHM) were included retrospectively in our study. Preoperative hypotonic LES was defined by a mean residual pressure of the lower esophageal sphincter 14.72. We also evaluated postoperative manometric changes at the esophageal-gastric junction. Sixty-nine patients (54 females and 15 males) had pre- and postoperative HRM and pHM. The mean age was 45.9 ± 9.8 years. The mean body mass index (BMI) was 47.5 ± 7.5 kg/m2. Hypotonic LES concerned 21 patients (30.4%) before sleeve gastrectomy. The mean time between the two esophageal monitorings was 32.1 ± 24.1 months. The sensitivity, specificity, positive predictive value, and negative predictive value of hypotonic LES to predict GERD were 31, 70, 52, and 48% respectively. The LES minimal residual pressure was not statistically decreased after sleeve gastrectomy (p = 0.24). Only the wave speed, esophageal length, and LES length were significantly reduced after SG (p = 0.029, 3.8 × 10−7 and 0.00032). Hypotonic LES has a poor predictive value on postoperative GERD. The LES’s length is significantly reduced after SG and this could be a factor explaining de novo reflux.

Aim. - Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a master regulator of low-density lipoprotein cholesterol (LDL-C) metabolism, acting as an endogenous inhibitor of the LDL receptor. While it has been shown that bariatric surgery differentially affects plasma LDL-C levels, little is known of its effects on plasma PCSK9 concentrations. Therefore, the present study aimed to: (i) investigate the effect of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on plasma PCSK9 concentrations; and (ii) correlate baseline or postoperative plasma PCSK9 concentration variations with anthropometric and metabolic parameters. Methods. - Fasting plasma PCSK9 levels were measured by ELISA in morbidly obese patients before and 6 months after bariatric surgery. Patients were recruited from three prospective cohorts (in Nantes and Colombes in France, and Antwerp in Belgium). Results. - A total of 156 patients (34 SG, 122 RYGB) were included. Plasma PCSK9, LDL-C and non-high-density lipoprotein cholesterol (non-HDL-C) levels were significantly reduced after RYGB (-19.6%, -16.6% and -19.5%, respectively; P < 0.0001), but not after SG. In all patients, postoperative PCSK9 change was positively correlated with fasting plasma glucose (FPG; r = 0.22, P = 0.007), HOMA-IR (r = 0.24, P = 0.005), total cholesterol (r = 0.17, P = 0.037) and non-HDL-C (r = 0.17, P = 0.038) variations, but not LDL-C. In contrast to what was observed for glucose parameters (FPG, HOMA-IR), correlation between PCSK9 and non-HDL-C changes after RYGB was independent of total weight loss. Conclusion. - RYGB, but not SG, promotes a significant reduction in plasma PCSK9 levels, and such changes in circulating PCSK9 levels after RYGB appear to be more associated with glucose improvement than with lipid homoeostasis parameters. (C) 2020 Published by Elsevier Masson SAS.

Background Ehlers-Danlos syndrome (EDS) is a heterogeneous disease affecting connective tissues. EDS patients have a high susceptibility for developing anastomotic leak after visceral surgery. Although patients with EDS can also develop severe obesity and might be referred to bariatric surgery, there is just 1 case report in the literature regarding the outcomes of bariatric surgery in this specific context. Objective To report the cases of patients with EDS and severe obesity that underwent bariatric surgery. Setting Five French hospitals (University Hospital of Nantes, APHP Pitie Salpetriere Hospital, APHP Bichat Hospital, Clinique St Gregoire Rennes, and Clinique Mutualiste de l’Estuaire St Nazaire). Methods We report the cases of 7 patients with EDS and severe obesity who underwent surgery. Results All patients showed classical postoperative course except for 1 case of excessive bleeding. There was no increased pain, leak, and solid parietal healing was achieved in all patients at 1 month postoperatively. The percent excess weight loss at 1 and 6 months were 13.9 ± 3.8% and 45.3 ± 16%, respectively. Conclusion Our study shows that bariatric surgery is a relevant and apparently safe surgical option to consider in severely obese patients with EDS.

Isomer ratios between certain polycyclic aromatic compounds in produced oils and bitumen extracts change according to the maturity of the source rock, similar to results obtained from visual vitrinite reflectance and pyrolysis. For example, empirical relationships between methyldibenzothiophene (MDBT) and methylphenanthrene compounds correlate to these parameters. However, isomer ratios and their corresponding empirical relationships are not universally applicable. Their concentrations are source-specific, influenced by maceral type, and change with the kinetics of the source rock that is generating the hydrocarbon. The organosulfur content in kerogen can strongly affect the kinetics by lowering the activation energy, resulting in the generatation of hydrocarbons at lower temperatures than other source rocks. This can cause uncertainty in the calibration of basin models for predicting the timing of hydrocarbon generation, expulsion, and migration, especially for Type II-S sources. Presented are the results of a study conducted on Type II-S carbonate organofacies from the United States and the Middle East that integrates the MDBTs extracted from bitumen and measured in produced oil with other ancillary maturity indicators. The MDBT isomers show a correlation between Tmax and hydrogen index that allows for the development of maturity models to accurately predict a %Ro equivalent from immature to condensate/wet gas maturity. Results indicate the often-utilized empirical equations developed from the methylphenanthrenes are not applicable for determining maturity of marine Type II-S organofacies. Instead, the MDBT-HI and MDBT-Tmax methods provide more reliable estimates of maturity for the Type II-S, marine carbonate organofacies to aid in validating basin model predictions for hydrocarbon generation.

Objective Alternative activation (M2) of adipose tissue resident macrophage (ATM) inhibits obesity-induced metabolic inflammation. The underlying mechanisms remain unclear. Recent studies have shown that dysregulated lipid homeostasis caused by increased lipolysis in white adipose tissue (WAT) in the obese state is a trigger of inflammatory responses. We investigated the role of M2 macrophages in lipotoxicity-induced inflammation. Methods We used microarray experiments to profile macrophage gene expression regulated by two M2 inducers, interleukin-4 (Il-4), and peroxisome proliferator-activated receptor delta/gamma (Pparδ/Pparγ) agonists. Functional validation studies were performed in bone marrow-derived macrophages and mice deprived of the signal transducer and activator of transcription 6 gene (Stat6; downstream effector of Il-4) or Pparδ/Pparγ genes (downstream effectors of Stat6). Palmitic acid (PA) and β-adrenergic agonist were employed to induce macrophage lipid loading in vitro and in vivo, respectively. Results Profiling of genes regulated by Il-4 or Pparδ/Pparγ agonists reveals that alternative activation promotes the cell survival program, while inhibiting that of inflammation-related cell death. Deletion of Stat6 or Pparδ/Pparγ increases the susceptibility of macrophages to PA-induced cell death. NLR family pyrin domain containing 3 (Nlrp3) inflammasome activation by PA in the presence of lipopolysaccharide is also increased in Stat6−/− macrophages and to a lesser extent, in Pparδ/γ−/− macrophages. In concert, β-adrenergic agonist-induced lipolysis results in higher levels of cell death and inflammatory markers in ATMs derived from myeloid-specific Pparδ/γ−/− or Stat6−/− mice. Conclusions Our data suggest that ATM cell death is closely linked to metabolic inflammation. Within WAT where concentrations of free fatty acids fluctuate, M2 polarization regulated by the Stat6-Ppar axis enhances ATM's tolerance to lipid-mediated stress, thereby maintaining the homeostatic state., Highlights • Cell survival is transcriptionally regulated by macrophage alternative activation. • Fatty acid-triggered cell death is increased in Pparδ/γ−/− or Stat6−/− macrophages. • Il-4-Stat6 signaling suppresses lipotoxicity-induced inflammasome activation. • The Stat6-Pparδ/γ axis protects ATMs against lipolysis-induced cell death in vivo.

International audience; Background: Obesity is well known to increase the risk of gastroesophageal reflux disease (GERD). The impact of sleeve gastrectomy (SG) on GERD is still discussed but seems to be associated with the development of de novo GERD or the exacerbation of preexisting GERD.Objective: The objective of this study was to evaluate the impact of preoperative pH monitoring, using the DeMeester score (DMS), on the risk of conversion to Roux-en-Y gastric bypass (RYGB) after SG.Setting: University Hospital in Nantes, France.Methods: This monocentric study reported the results of a retrospective chart review of 523 obese individuals treated between 2011 and 2018. All patients underwent primary bariatric surgery; 95% had undergone an SG. GERD diagnosis was established with preoperative DMS based on 24-hour esophageal pH monitoring.Results: Preoperative DMS was identified in 423 patients (86%). Sixty-seven patients (14%) underwent a second bariatric procedure; among them, 36 (54%) have been converted to RYGB because of GERD. There was no significant difference between preoperative DMS (16.1 ± 22 versus 13.7 ± 14, P = .37) in patients undergoing conversion for GERD and the nonconverted ones. The sensitivity, specificity, positive predictive, and negative predictive values of the preoperative DMS for predicting conversion to RYGB were 25%, 66%, 7%, and 4%, respectively. In patients who underwent a conversion for GERD, DMS (P < .002), rates of esophagitis (P = .035), and hiatal hernia (P = .039) significantly increased after SG.Conclusion: Preoperative DMS alone is not predictive of the risk of conversion of SG to RYGB for GERD.

International audience; Vertical banded gastroplasty (VBG), introduced by Mason in 1982, is now discarded because of important long-term complications and technical difficulties to do revisional surgery. We investigated the long-term complications of VBG in our center and compared it with the literature data. Patients who underwent an open VBG at the University Hospital of Nantes between October 1991 and May 2006 were included. We reviewed preoperative clinical data, long-term outcome in weight loss, complications, and revisional surgeries with a long follow-up. Sixty-three patients (52 women and 11 men) were included, with a mean age of 43 ± 10 years and a body mass index of 46.7 ± 8.3 kg/m². The mean follow-up was 8.2 ± 4.2 years. At the end of follow-up, the mean excess weight loss (EWL) was 29.8%. Long-term success (excess weight loss > 50%) of the procedure was observed in 25 patients (39.7%). A second intervention was performed in 15 patients (23.8%), and three needed a third redo procedure. Six patients (40%) had this new intervention for late complications, and nine (60%) for weight regain. Weight loss is satisfying in the long term although the rate of reintervention is high. Long-term complication can be severe, especially with gastric stenosis that could lead to esophageal cancer. A second reintervention could be technically demanding, especially by laparoscopy, and the patients should be referred to a specialized center.

Complex permittivity measurements were conducted for four crude oils and a gas condensate at temperatures ranging from 25 °C to 125 °C. The measurements were conducted using a liquid test fixture and results are reported for frequencies between 50 kHz and 5 MHz. Geochemical analyses were performed, and the main components of the liquid hydrocarbons were identified and, in the process, both the provenance and genesis of the crude oils were determined. Analysis of the permittivity measurements show that, within uncertainty, the real part of the dielectric permittivity spectra can be related back to the density (API), maturity, and secondary chemical alteration. The behavior of the imaginary part, although dominated by the conductivity, which is correlated to the asphaltene, metal, and aromatic content of the hydrocarbons studied, showed an interesting result that lead to the prediction of inseparable water, which was further verified by Nuclear Magnetic Resonance (NMR) measurements. In addition, results at 25 °C were combined with those obtained from two high accuracy, multipoint re-entrant resonant cavities for nine different frequencies between 170 MHz and 8.6 GHz. Results predict relaxation process between 5 MHz and 100 MHz, in agreement with the literature.

Summary Acoustic-velocity measurements are an important nondestructive way to investigate dynamic rock-mechanical properties. Water content and bedding-plane-induced anisotropy are reported to significantly affect the acoustic velocities of siliciclastic sandstones and laminated carbonates. This relationship in organic-rich shales, however, is not well-understood and has yet to be investigated. The mechanical properties of organic-rich shales are affected by changes in water content, laminations, total organic content (TOC), and microstructures. In particular, kerogen density that accompanies changes in the composition of the TOC during maturity can significantly influence the acoustic responses within source rocks. To understand how these variables influence acoustic responses in organic shales, two sets of cores from the Eagle Ford shale were investigated: one set cut parallel to bedding and the other perpendicular to bedding. Textures of the samples from each set were characterized by use of computed-tomography (CT) scanning. Nuclear magnetic resonance (NMR) was used to measure the water content, and X-ray diffraction (XRD) to analyze the mineralogy. Scanning electron microscope (SEM) was also used to characterize the microstucture. Acoustic-velocity measurements were then made on each set at various confining pressures with the ultrasonic pulse-transmission technique. The results show that confining pressure, water content, and laminations have significant impact on both compressional-wave (P-wave) and shear-wave (S-wave) velocity. Both velocities increase as confining pressure increases. Velocities measured from cores cut parallel to bedding are, on average, 20% higher than those cut perpendicular to bedding. Increasing water content decreases both velocities. The impact of water content on shear velocity was found to be significant compared with the response with compressional velocity. As a result, the water content was found to lower both Young's modulus and shear modulus, which is opposite to the reported results in conventional reservoir lithology. In addition, both P- and S-wave velocities show a linear decrease as TOC increases, and they both decrease with increasing of clay content. The mechanisms that lead to water-content alteration of rock-mechanical properties might be a combined result of the clay/water interaction, the chemical reaction, and the capillary pressure changes.

IL-13 hits the gym Interleukin-13 (IL-13) is a cytokine secreted by T cells, innate lymphoid cells (ILC2s), and granulocytes. It acts as a central mediator in allergy and antihelminth defense with various effects. Knudsen et al. report a distinct role for IL-13 in exercise and metabolism (see the Perspective by Correia and Ruas). Mice subjected to endurance training showed increases in circulating IL-13, which correlated with ILC2 expansion in the muscles. By contrast, exercise-induced increases in muscle fatty acid utilization and mitochondrial biogenesis were erased when mice lacked IL-13. Activation of signaling pathways downstream of the muscle IL-13 receptor was key to this effect. Intramuscular injection of adenoviral IL-13 could recapitulate exercise-induced metabolic reprogramming. This signaling pathway may have evolved to combat the metabolic stresses of parasite infection. Science , this issue p. eaat3987 ; see also p. 470