Deep Locations Research Articles

Influence of arm position on the first pass success rates of ultrasound-guided infraclavicular axillary vein cannulation in spontaneously breathing patients: A randomised clinical trial.

Significant collapsibility during spontaneous respiration, deeper location, and smaller vein size are key challenging factors to safe infraclavicular axillary vein cannulation. Arm abduction reduces collapsibility, but interventional data supporting this observation is lacking. This study investigates the effect of neutral and abducted arm position on the first pass success rate of infraclavicular axillary vein cannulation in spontaneously breathing patients. One hundred and twelve patients were randomly assigned to two arm positions, neutral or abducted by 90° at the shoulder joint. Under ultrasound guidance, the infraclavicular axillary vein was cannulated using an in-plane approach. The primary outcome was the first pass success rate of guidewire placement in the infraclavicular axillary vein. The secondary outcome measures were the number of attempts for successful cannulation, failure rate, and catheter tip malposition. Fifty-two patients in the neutral arm and fifty-six patients in the arm abduction group were compared according to the intention to treat analysis. The abducted arm position was associated with a higher first pass success rate (RR = 3.39, 95% CI = 1.47-7.85; p = 0.004) with fewer attempts (p = 0.005), lower failure rate (RR = 1.37, 95% CI = 1.16-1.61; p = 0.000) and lower catheter tip malposition (1.5 vs 15.8%; p = 0.012) when compared to the neutral arm position. Abducted arm position resulted in a significantly higher first pass success rate with a lower failure rate and catheter tip malposition during ultrasound-guided infraclavicular axillary vein cannulation in spontaneously breathing patients.

An aberration correction approach for single and dual aperture ultrasound imaging of the abdomen

Abdominal ultrasound image quality is hampered by phase aberration, that is mainly caused by the large speed-of-sound (SoS) differences between fat and muscle tissue in the abdominal wall. The mismatch between the assumed and actual SoS distribution introduces general blurring of the ultrasound images, and acoustic refraction can lead to geometric distortion of the imaged features. Large aperture imaging or dual-transducer imaging can improve abdominal imaging at deep locations by providing increased contrast and resolution. However, aberration effects for large aperture imaging can be even more severe, which limits its full potential. In this study, a model-based aberration correction method for arbitrary acquisition schemes is introduced for delay-and-sum (DAS) beamforming and its performance was analyzed for both single- and dual-transducer ultrasound imaging. The method employs aberration corrected wavefront arrival times, using manually assigned local SoS values. Two wavefront models were compared. The first model is based on a straight ray approximation, and the second model on the Eikonal equation, which is solved by a multi-stencils fast marching method. Their accuracy for abdominal imaging was evaluated in acoustic simulations and phantom experiments involving tissue-mimicking and porcine material with large SoS contrast (∼100 m/s). The lateral resolution was improved by up to 90% in simulations and up to 65% in experiments compared to standard DAS, in which the use of Eikonal beamforming generally outperformed straight ray beamforming. Moreover, geometric distortions were mitigated in multi-aperture imaging, leading to a reduction in position error of around 80%. A study on the sensitivity of the aberration correction to shape and SoS of aberrating layers was performed, showing that even with imperfect segmentations or SoS values, aberration correction still outperforms standard DAS.

Proposal for a novel classification of benign parotid tumors based on localization

ObjectivePostoperative facial nerve paralysis is the most problematic complication after surgical treatment of parotid tumors. Localization of tumors is highly relevant for the surgical approach, but existing classification systems do not focus on the association between localization and surgical technique. Therefore, we created a new localization-based classification system for benign parotid tumors and investigated the characteristics of tumors in each localization and the frequency of postoperative facial nerve paralysis by retrospectively applying the classification to previous cases. MethodsFirst, we defined 6 portions of the parotid gland (upper, U; lower, L; posterior, P; anterior, A; superficial, S; deep, D) by dividing the transverse plane into an upper and lower portion at the mandibular marginal branch, the longitudinal plane into a posterior and anterior portion at the midline of the parotid anteroposterior diameter, and the sagittal plane into a superficial and deep portion along the course of the facial nerve. Then, we defined 8 locations by combining the 6 portions in all possible ways (i.e., U-P-S, U-P-D, U-A-S, U-A-D, L-P-S, L-P-D, L-A-S, L-A-D). We used this classification to define the tumor localization in 948 patients who had undergone partial superficial parotidectomy for benign parotid tumors and then investigated the incidence, histopathological type, signs/symptoms, diagnosis, surgery, and complications in each area. ResultsPleomorphic adenomas comprised approximately 70% of tumors in the upper portion but only approximately 35% in the lower portion. The rate of postoperative facial nerve paralysis was significantly higher for tumors in deep locations than in superficial locations (33.9% vs 14.9%, respectively), and the odds ratios for postoperative facial nerve paralysis in the U-P-D and U-A-D locations were 7.6 and 4.8 compared to the L-P-S location. When maximum diameter, operation time, bleeding volume, sex (reference: female), and age were added as control variables, the odds ratios were 4.2 and 3.0. ConclusionDetermining tumor localization preoperatively with the new localization-based classification of parotid tumors is helpful not only for predicting the histopathological type but also for predicting surgical complications, particularly postoperative facial nerve paralysis.

Primary Stereotactic Radiosurgery Provides Favorable Tumor Control for Intraventricular Meningioma: A Retrospective Analysis.

The surgical resection of intraventricular meningiomas (IVMs) remains challenging because of their anatomically deep locations and proximity to vital structures, resulting in non-negligible morbidity and mortality rates. Stereotactic radiosurgery (SRS) is a safe and effective treatment option, providing durable tumor control for benign brain tumors, but its outcomes for IVMs have rarely been reported. Therefore, the goal of the present study was to evaluate the SRS outcomes for IVMs at our institution. This retrospective observational study included 11 patients with 12 IVMs with a median follow-up period of 52 months (range, 3-353 months) treated with SRS using the Leksell Gamma Knife. Nine (75%) tumors were located in the trigone of the lateral ventricle, two (17%) in the body of the lateral ventricle, and one (8%) in the third ventricle. Tumor control was achieved in all cases, and seven (55%) decreased in size. Post-SRS perifocal edema was observed in four (37%; three asymptomatic and one symptomatic but transient) patients, all of which were resolved by the last follow-up. SRS appears to provide safe and excellent tumor control for IVMs. A longer follow-up with a larger number of cases is desired for a more solid conclusion.

Microbes and hydrothermal environments: An annotated selection of World Wide Web sites relevant to the topics in environmental microbiology.

This article written by Smithsonian Ocean staff provides a good overview of hydrothermal vent communities suitable for non-scientific readers. This report reviews the microbial diversity and microbe-mineral interactions in deep-ocean hydrothermal environments. This report dealt with the rich taxonomic diversity in vent communities, with a particular focus on those within the tubeworm Ridgeia piscesae. This article covered microbial succession during a change from active to inactive deep-sea sulfide chimneys. This paper is a broad overview of microbial population at deep-sea areas containing hydrothermal vents. This page provides a summary of a published paper on gene transfer in deep-sea hydrothermal vent bacteria. It contains a link to the original article. This article by Jannasch and Mottl is one of the classics in the field of hydrothermal vent chemistry and microbiology. There are numerous videos on life in deep-sea environments. This is one of the longest and most comprehensive of those. This page of the Microbe Wiki describes deep sea vent properties, global locations, bacterial communities, and eukaryotic organisms present in those environments. This report describes the isolation and characterization of a green sulfur bacterial species from a deep-ocean hydrothermal vent that is proposed to use geothermal radiation as a source of photons to be absorbed by its photosynthetic pigments. This article reviews knowledge of, and techniques for studying, hydrogen uptake and hydrogen evolving enzymes involved in hydrogen cycling at hydrothermal vents. This study samples several deep-sea hydrothermal vents to sequence viruses that were present. The general conclusions were that diverse viruses were present with different assemblages that are highly localized to specific areas and hosts.

Floating Offshore Wind Turbines: Current Status and Future Prospects

Offshore wind energy is a sustainable renewable energy source that is acquired by harnessing the force of the wind offshore, where the absence of obstructions allows the wind to travel at higher and more steady speeds. Offshore wind has recently grown in popularity because wind energy is more powerful offshore than on land. Prior to the development of floating structures, wind turbines could not be deployed in particularly deep or complicated seabed locations since they were dependent on fixed structures. With the advent of floating structures, which are moored to the seabed using flexible anchors, chains, or steel cables, wind turbines can now be placed far offshore. The deployment of floating wind turbines in deep waters is encouraged by several benefits, including steadier winds, less visual impact, and flexible acoustic noise requirements. A thorough understanding of the physics underlying the dynamic response of the floating offshore wind turbines, as well as various design principles and analysis methods, is necessary to fully compete with traditional energy sources such as fossil fuels. The present work offers a comprehensive review of the most recent state-of-the-art developments in the offshore wind turbine technology, including aerodynamics, hydromechanics, mooring, ice, and inertial loads. The existing design concepts and numerical models used to simulate the complex wind turbine dynamics are also presented, and their capabilities and limitations are discussed in detail.

Image restoration for blurry optical images caused by photon diffusion with deep learning.

Optical macroscopic imaging techniques have shown great significance in the investigations of biomedical issues by revealing structural or functional information of living bodies through the detection of visible or near-infrared light derived from different mechanisms. However, optical macroscopic imaging techniques suffer from poor spatial resolution due to photon diffusion in biological tissues. This dramatically restricts the application of optical imaging techniques in numerous situations. In this paper, an image restoration method based on deep learning is proposed to eliminate the blur caused by photon diffusion in optical macroscopic imaging. Two blurry images captured at orthogonal angles are used as the additional information to ensure the uniqueness of the solution and restore the small targets at deep locations. Then a fully convolutional neural network is proposed to accomplish the image restoration, which consists of three sectors: V-shaped network for central view, V-shaped network for side views, and synthetical path. The two V-shaped networks are concatenated to the synthetical path with skip connections to generate the output image. Simulations as well as phantom and mouse experiments are implemented. Results indicate the effectiveness of the proposed method.

Combined Effects of Liquefaction-Induced Lateral Spreading and Superstructure Inertial Loads on Pile Foundations

Pile foundations in sloping or gently sloped liquefiable soils are often subjected to a combination of inertial and lateral spreading loads. Current design codes vary significantly in terms of the methods used to analyze and design piles that are subjected to combined loading. The results from a full-scale shake table test on a 0.25-m-diameter reinforced concrete pile in gently sloping ground are used in this study to back-calculate the inertial loads, the kinematic loads, and the interaction between inertial and kinematic loads during seismic loading. It was found that large pile strains developed after liquefaction was triggered. The maximum pile strains (and curvatures) at shallow depths within the nonliquefiable crust were correlated with maximum inertial loads in the upslope direction that were resisted by a crust load applied in the downslope direction, indicating an out-of-phase interaction. The maximum pile strains (and curvatures) at deeper locations below the loose liquefiable sand were correlated with the maximum inertial loads in the downslope direction but without any resistance or driving load from the crust (i.e., no lateral spreading load during peak downslope inertial cycles). The lack of crust load during the downslope inertial cycles was attributed to the pile head outrunning the crust displacement, causing the pile to be pushed into a gap that had formed on the downslope front of the pile. The findings of this study contribute a data point to a wide range of inertial and kinematic interaction factors proposed by other studies and highlight the site- and project-dependency of interactions between inertial and kinematic loads.

Response of soil–pile–superstructure–quay wall system to lateral displacement under horizontal and vertical earthquake excitations

The excess pore water pressure generated under the combined vertical and horizontal earthquake excitations is generally greater than that under the unidirectional excitation, which may further affect the dynamic response of soil-pile-superstructure-quay wall (SPSQ) system. This study conducted a coupled effective-stress analysis for the response of SPSQ system to liquefaction-induced lateral displacement under horizontal and vertical earthquake excitations. To accurately describe the lateral displacement behind the quay wall, the liquefaction behavior of soils was described by a modified generalized plasticity model with parameters properly determined from laboratory tests. The numerical model of the SPSQ system was validated against the previously reported centrifuge model tests. The results show that the earthquake excitation with abundant low-frequency component causes greater residual lateral displacements of pile cap (ux,RC) and quay wall (ux,RQ) than that with abundant high-frequency component. The ux,RC and ux,RQ tend to increase as the peak vertical acceleration increases for both vertical and inclined piles. Increasing the fixity of the quay wall significantly reduces the influence of vertical ground motion on the ux,RC and ux,RQ. The polarity reversal of the vertical ground motion also has a significant effect on the ux,RC and ux,RQ and should be considered in the analyses. In addition, the lateral displacement of liquefied ground causes an amount of rotation of the cap of the inclined pile, probably leading to the potential shear failure at the head of piles. Special consideration should be given to the earthquake-induced shear force at deeper location because the shear force could be significantly greater than that at the head of both inclined and vertical piles in certain cases.

Zein-based injectable biomaterial and angiogenic activity through peptides produced by enzymatic degradation

Injectable biomaterials are gaining attention due to minimal invasiveness and precise implantation in deep anatomical locations. For tissue regeneration, controlling the degradation and improving vascularization are still the key issues to be resolved. Moreover, for protein-based biomaterials, immune response should be specially considered, although they have advantages such as biodegradability, their degraded products have innate bioactivity and can be utilized by our body. Zein, a plant protein, has been explored for biomedical applications. Recently, we have reported zein gel as a 3D printing ink for drug delivery systems. In this study, we extended the application of zein gel as an injectable biomaterial. Zein gels showed shear-thinning property and tunable yield stress, which is essential for injectability and shape adaptability. Polyvinylpyrrolidone (PVP) was added to the gel to accelerate the degradation and subsequently generate more bioactive peptides for their anti-inflammatory and angiogenic functions as evidenced by in vitro evaluation. Animal experiment using Sprague Dawley (SD) rats also showed a positive angiogenic response after subcutaneous implantation of zein gels with PVP. Bioactive peptides produced from zein degradation were responsible for the angiogenic response that was validated by adding zein degraded products to the gel. Overall, zein gel was proven a promising injectable biomaterial that can fill tissue defect and improve tissue regeneration with controllable degradation rate. Moreover, the enzyme-treated zein hydrolysates can be used as additives with angiogenic activity.

Enhancing flotation removal of unburned carbon from fly ash by coal tar-based collector: Experiment and simulation

The unburned carbon (UC) in fly ash is a vital parameter that governs the further utilization of fly ash in mortar and concrete industry. Flotation is an effective methodology for removing the UC from fly ash. However, the specific physicochemical properties of the UC particle surface make them difficult to float. In this study, a coal tar-based (CTB) collector was used to remove the UC from fly ash through flotation process. The adsorption mechanism of the CTB collector and diesel on the UC particle surface was characterized by scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), molecular dynamics (MD) simulation, and induction time tests. The levels of oxygen-containing functional groups and aromatic ring compounds present in the CTB collector were considerably higher than those in diesel. The oxygen-containing functional group contents on the untreated UC surface, the diesel-treated UC surface, and the CTB collector-treated UC surface decreased in that order. The MD simulation results indicated that the aromatic compounds (dibenzofuran and naphthalene, etc.) in the CTB collector interacted strongly and adsorbed at deep locations with the UC surface compared to the alkanes (dodecane, diesel, etc.). The alkanes are indispensable as the collector in the fly ash flotation process and synergize with aromatic compounds to improve the mobility of water molecules on the UC surface. The CTB collector significantly enhanced the floatability of the UC particle and hence improved the flotation removal of UC from fly ash.

Deep learning-based quantitative estimation of lymphedema-induced fibrosis using three-dimensional computed tomography images

In lymphedema, proinflammatory cytokine-mediated progressive cascades always occur, leading to macroscopic fibrosis. However, no methods are practically available for measuring lymphedema-induced fibrosis before its deterioration. Technically, CT can visualize fibrosis in superficial and deep locations. For standardized measurement, verification of deep learning (DL)-based recognition was performed. A cross-sectional, observational cohort trial was conducted. After narrowing window width of the absorptive values in CT images, SegNet-based semantic segmentation model of every pixel into 5 classes (air, skin, muscle/water, fat, and fibrosis) was trained (65%), validated (15%), and tested (20%). Then, 4 indices were formulated and compared with the standardized circumference difference ratio (SCDR) and bioelectrical impedance (BEI) results. In total, 2138 CT images of 27 chronic unilateral lymphedema patients were analyzed. Regarding fibrosis segmentation, the mean boundary F1 score and accuracy were 0.868 and 0.776, respectively. Among 19 subindices of the 4 indices, 73.7% were correlated with the BEI (partial correlation coefficient: 0.420–0.875), and 13.2% were correlated with the SCDR (0.406–0.460). The mean subindex of Index 2 left( {frac{{P_{Fibrosis, in, Affected} - P_{Fibrosis, in, Unaffected} }}{{P_{Limb, in, Unaffected} }}} right) presented the highest correlation. DL has potential applications in CT image-based lymphedema-induced fibrosis recognition. The subtraction-type formula might be the most promising estimation method.

Salinity and Temperature Variations near the Freshwater-Saltwater Interface in Coastal Aquifers Induced by Ocean Tides and Changes in Recharge

The temperature distribution of shallow sectors of coastal aquifers are highly influenced by the atmospheric temperature and recharge. However, geothermal heat or vertical fluxes due to the presence of the saline wedge have more influence at deeper locations. In this study, using numerical models that account for variable density, periodic oscillations of temperature have been detected, and their origin has been attributed to the influence exerted by recharge and tides. The combined analysis of field data and numerical models showed that the alternation of dry and wet periods modifies heat distribution in deep zones (>100 m) of the aquifer. Oscillations with diurnal and semidiurnal frequencies have been detected for groundwater temperature, but they show differences in terms of amplitudes and delay with electrical conductivity (EC). The main driver of the temperature oscillations is the forward and backward displacement of the freshwater–saltwater interface, and the associated thermal plume generated by the upward flow from the aquifer basement. These oscillations are amplified at the interfaces between layers with different hydraulic conductivity, where thermal contours are affected by refraction.

Shale-gas potential from Cretaceous succession in South Africa’s Orange Basin: Insights from integrated geochemical evaluations

Shale sediments were collected from four Cretaceous stratigraphic units across four explorations well locations in South Africa’s Orange Basin and analysed to determine organic-matter characteristics, such as amount, quality, thermal maturity, and their viability as gas resources. The geochemical results show that the Cretaceous shales contain moderate organic quantities, as shown by TOC averagely up to 1.29%. The organic facies consist primarily of Type III kerogen, as proven alongside low hydrogen indexes between 40 and 133 mg HC/g TOC. As seen under a reflected light microscope, the dominance of such land plant-rich organic matter is in harmony with the significant amount of Vitrinite macerals. These organic sediments can produce primarily gas when they mature. The geological and geochemical properties of the organic sediments, chiefly Type III kerogen, generate both wet and dry gas, particularly when adequate thermal maturity is enhanced at deeper locations. Thus, the Orange Basin is considered promising for shale gas exploration and production.

Surgical aspiration versus excision for intraparenchymal abscess: a systematic review and Meta-analysis

Brain abscesses are associated with considerable morbidity and mortality, requiring timely intervention to achieve favourable outcomes. With the advent of high-resolution computed tomography (CT) imaging, mortality following both aspiration and excision of brain abscesses has improved markedly. As a result, there has been a marked shift in neurosurgical practice with aspiration eclipsing excision as the favoured first-line modality for most abscesses. However, this trend lacks sufficient supporting evidence, and this systematic review and meta-analysis seeks to compare aspiration and excision in the treatment of brain abscess. Twenty-seven studies were included in the systematic review, and seven comparative papers in meta-analysis. Aspiration was the chosen technique for 67.5% of patients. Baseline characteristics from the studies included only in the systematic review demonstrated that abscesses treated by aspiration were typically larger and in a deeper location than those excised. In the meta-analysis, we initially found no significant difference in mortality, re-operation rate, or functional outcome between the two treatment modalities. However, sensitivity analysis revealed that excision results in lower re-operation rate. On average, the included studies were of poor quality with average Methodological Index for Non-Randomized Studies (MINORS) scores of 10.3/16 and 14.43/24 for non-comparative and comparative papers respectively. Our study demonstrates that excision may offer improved re-operation rate as compared to aspiration for those abscesses where there is no prior clinical indication for either modality. However, no differences were found with respect to mortality or functional outcome. Evidence from the literature was deemed low quality, emphasizing the need for further investigation in this field, specifically in the form of large, well-controlled, comparative trials.

Submammary Implantation of Internal Pulse Generators for Deep Brain Stimulation: Long-Term Follow-up of Device Acceptance and Quality of Life in Women

A submammary approach to implanting pulse generators is innovative and has yielded good aesthetic results in the current literature. It was our aim to make a comparison of patient device acceptance, tolerance, and complications between submammary and abdominal device locations in deep brain stimulation. Twenty-five and 28 patients were included in the submammary and abdominal groups, respectively. Our primary criterion was patient acceptance that was calculated using total Florida Patient Acceptance Survey (FPAS) scores in each group. Secondarily, tolerance was assessed in the submammary group by means of a specific questionnaire. Total FPAS scores from the submammary group [total FPAS: 77.1 versus 74.7, P=0.29] revealed no significant difference when compared with the abdominal group. The same similarities were observed regarding the 4 subscales: return to function [16.3 versus 15.8, P=0.53], device-related distress [22.0 versus 21.3, P=0.31], body image concerns [9.2 versus 8.6, P=0.14], and positive appraisal [17.8 versus 17.4, P=0.58]. Tolerance was reported as good by the majority of the women from the submammary group. There was no evidence of higher infection rates in the submammary implantation (SMI) group. SMI is a satisfactory alternative to other deep brain stimulation locations. SMI is a feasible option for any young woman who is eligible for deep brain stimulation.

Enhanced Photoacoustic Visualisation of Clinical Needles by Combining Interstitial and Extracorporeal Illumination of Elastomeric Nanocomposite Coatings.

Ultrasound (US) image guidance is widely used for minimally invasive procedures, but the invasive medical devices (such as metallic needles), especially their tips, can be poorly visualised in US images, leading to significant complications. Photoacoustic (PA) imaging is promising for visualising invasive devices and peripheral tissue targets. Light-emitting diodes (LEDs) acting as PA excitation sources facilitate the clinical translation of PA imaging, but the image quality is degraded due to the low pulse energy leading to insufficient contrast with needles at deep locations. In this paper, photoacoustic visualisation of clinical needles was enhanced by elastomeric nanocomposite coatings with superficial and interstitial illumination. Candle soot nanoparticle-polydimethylsiloxane (CSNP-PDMS) composites with high optical absorption and large thermal expansion coefficients were applied onto the needle exterior and the end-face of an optical fibre placed in the needle lumen. The excitation light was delivered at the surface by LED arrays and through the embedded optical fibre by a pulsed diode laser to improve the visibility of the needle tip. The performance was validated using an ex-vivo tissue model. An LED-based PA/US imaging system was used for imaging the needle out-of-plane and in-plane insertions over approach angles of 20 deg to 55 deg. The CSNP-PDMS composite conferred substantial visual enhancements on both the needle shaft and the tip, with an average of 1.7- and 1.6-fold improvements in signal-to-noise ratios (SNRs), respectively. With the extended light field involving extracorporeal and interstitial illumination and the highly absorbing coatings, enhanced visualisation of the needle shaft and needle tip was achieved with PA imaging, which could be helpful in current US-guided minimally invasive surgeries.

Evaluating biodegradable alternatives to plastic mesh for small‐scale oyster reef restoration

Polyethylene plastic mesh is commonly used for containing oyster shells in small‐scale oyster reef restoration, but environmental and public health concerns have prompted investigations of biodegradable alternatives. Shallow (<0.5 m) and deep (approximately 1 m) oyster reefs (approximately 6 m2) were constructed in the Mission‐Aransas Estuary, Texas, U.S.A., in March 2020 using recycled oyster shells placed into four different replicated mesh bag types: polyethylene (plastic) and three biodegradable alternatives (cellulose, cotton, and jute). Biodegradable alternatives (cellulose, cotton, and jute) all completely degraded within 2 months of deployment, leaving piles of loose shell, while polyethylene bags remained intact. Despite rapid degradation, the biodegradable/loose shell successfully recruited and developed larger oysters (mean of 46 mm) than on the polyethylene‐bagged shell (mean of 40 mm) after 7 months, although at less than half the density. Associated motile fauna density in the bagged shell was 2.4 times higher than in the loose shell after 7 months at both the deep and shallow locations. Faunal community composition and diversity varied more with reef depth than by bag type. The total cost of using polyethylene bags was lower than for biodegradable alternatives (22–45% the cost of cellulose, 35–72% the cost of jute, 49–99% the cost of cotton). However, because our estimate of the environmental cost of polyethylene plastic mesh only included impacts on marine natural capital, the true cost is likely much higher. Despite higher costs, biodegradable alternatives can still be successful for use in small‐scale oyster restoration events without introducing plastics into the marine environment.

Parametrial endometriosis: A predictive and prognostic factor for voiding dysfunction and complications

ObjectiveParametrial involvement (PI) in endometriosis is poorly defined resulting in an underestimation of its impact during surgical excision. The aim of our study was to assess the surgical complications associated with parametrectomy during surgery for endometriosis. Our secondary objective was to compare the surgical complications rates of a parametrectomy to the excision of other deep pelvic endometriotic locations. Study designPatients who underwent surgery for deep pelvic endometriosis from 2013 to 2018 in a French referral center were retrospectively included. Surgical complications were assessed according to whether a parametrectomy had been performed. The extent of surgery (colpectomy, torus, utero-sacral (USL) and/or rectal resection) was also assessed. Voiding dysfunction was defined as the need for self-catheterization ≥1 month and intra and postoperative complications were graded using the Clavien-Dindo classification (CDC). ResultsWe included 753 patients: 285 (37.8 %) with PI. Patients with PI had higher ASRM scores and more extensive surgery than those without. These patients also had higher rates of voiding dysfunctions (17.5 % versus 8.98 %, p < 0.01), and postoperative complications (44.6 % versus 24.6 %, p < 0.01), including major complications (CDC 3–4) (14.7 % vs 8.5 %, p = 0.01). The extent of the surgical resection of endometriosis was strongly associated with surgical complications after multivariable analysis, and the addition of a parametrectomy during surgery greatly increased rates of adverse postoperative events. Voiding dysfunction was frequent in women with combined resection of the torus, utero-sacral ligaments, parametrium and vagina (adjusted OR = 37.28, 95 %CI = 6.84–203.11, p < 0.01, reference: resection of the USL). ConclusionParametrectomy significantly impacts postoperative complications in patients undergoing surgery for endometriosis.

Multistage fracturing history in the Paleocene lacustrine shale oil reservoirs of the Subei Basin, Eastern China

This study examines sealed fractures in core samples from the Paleocene organic-rich lacustrine shales of the Gaoyou Depression, Subei Basin, China, using a multi-pronged approach to elucidate the interplay between fracture propagation and fluid circulation in shaly successions. Based on petrography, geochemistry, and geochronology of fracture-filling minerals, four generations of vein emplacement (denoted Types A-D) were identified. These were attributed to successive episodes of burial diagenesis, tectonism, and uplift occurring at different phases of basin evolution. These vein generations were then inserted into the temporal-spatial framework derived from basin modeling, leading to a reconstruction of the fracture diagenesis history in the Funing shales. Two of the vein generations contain evidence for two phases of oil migration marked by two types of oil inclusions with different fluorescence.It has been shown that the studied lacustrine shales were deposited at ca. 60.2–58.0 Ma. The earliest vein generation, represented by antitaxial beef calcite veins sub-perpendicular to shale bedding, propagated in incompletely consolidated shales within a regional thrust regime related to the Wubao Movement. The vein nucleation during a short-lived burial following initial deposition was also evidenced by the presence of monoliquid inclusions in the veins and calcite LA-ICP-MS U–Pb age (57.7 ± 3.7 Ma). Tectonic compressive stress together with overpressures arising from horizontal and vertical disequilibrium compaction were interpreted as being responsible for this fracturing episode. The second vein generation is bedding-parallel, oil inclusion-rich stretching calcite veins with a crack-seal texture, formed concurrently with kerogen maturation and early oil generation at moderate burial depths. The vein crack-seal fills containing yellow fluorescing oil inclusions provide evidence for episodic oil expulsion in response to cyclic rises and drops in pore pressure during the oil window. Bedding-parallel beef calcite veins characterized by antitaxial growth represent the next vein generation, emplaced during the maximum burial period (ca. 41.9 ± 2.7 Ma). The vein fibers have tracked the horizontal displacement of the wall rocks, likely related to lateral shortening before or at the initiation of Late Eocene basin inversion. The first three vein generations were generated in a relative closed fluid system, with vein fill sourced locally. Host-rock carbonate components and/or earlier diagenetic carbonates were dissolved and then mobilized into these veins. By contrast, the last vein generation with blocky calcite and barite cementation is associated with input of externally derived hydrothermal fluids. The evidence comes from abnormally high fluid-inclusion homogenization temperature (Th) and salinity data, as well as the fact that Ba and sulfate were sourced from the underlying evaporite layers rather than local shales. We thus infer that cross-stratal faulting during the uplift related to the Sanduo Movement resulted in the opening of initial hydraulically closed fluid system. This episode of tectonically-driven hydrothermal circulation from deeper locations in the basin into the Funing shales led to the mixing of oil-bearing pore fluids with exotic basinal hot brines. This also accounts for the presence of abundant blue-green fluorescing oil inclusions and significantly elevated fluid salinity. Overall, this study emphasizes that during basin evolution, differences in tectonic settings and the diagenetic boundary conditions under which veins formed results in different fracturing mechanisms and associated fluid-flow regimes in shale sequences, with consequent effects on vein attributes and mineralization.