Defect Depth Research Articles

Comparison between discarded facemask and common plastic waste on microbial colonization and physiochemical properties during aging in seawater

Facemasks are indispensable for preventing the spread of COVID-19. However, improper disposal of discarded facemasks has led to their contamination in the marine environment. To understand the environmental risk of this emerging plastic pollution, it’s important to clarify the features that distinguish discarded facemasks from common plastic waste during aging. This study compared the microbial colonization, degradation-related enzymes, and physicochemical properties among surgical masks, polystyrene cups, polycarbonate bottles, and polyethylene terephthalate bottles in their aging processes in natural seawater. Compared to the other plastic wastes, surgical masks were colonized by the most diverse microorganisms, reaching 1521 unique prokaryotic OTUs after 21-day exposure in seawater. Moreover, the activity of eukaryotic enzymes associated with plastic degradation was 80-fold higher than that in seawater, indicating that the colonized eukaryotes would be the major microorganisms degrading the surgical masks. Meanwhile, the nano-sized defects (depth between 8 and 61 nm) would evolve into cracks of bigger sizes and result in the breakage of the microfibers and releasing microplastics into the ocean. Overall, our study demonstrated a distinctive plastisphere occurred in surgical masks from both microbial and physiochemical aspects. This work provides new insights for assessing the potential risk of plastic pollution caused by the COVID-19 pandemic.

Association between defect morphology and healing of intrabony defects treated with minimally invasive non-surgical therapy: A pilot exploratory analysis of two cohorts.

The aim of this study was to explore the associations between defect morphology (defined by clinical and radiographic parameters) and the healing of periodontal intrabony defects treated with minimally invasive non-surgical therapy (MINST). MINST has shown to result in favorable clinical and radiographic improvements in intrabony defects. However, it is not clear which types of intrabony defects are most suitable for this treatment. Clinical and radiographic analyses were carried out in a total of 71 intrabony defects treated with MINST belonging to two previously published studies. Baseline defect characteristics were analyzed and related to clinical and radiographic outcomes at 12 months post-MINST with or without adjunctive enamel matrix derivative. No associations were detected between defect depth, angle and predicted number of walls and clinical and radiographic healing 12 months post-MINST. No evidence emerged for associations between defect characteristics and healing following MINST. These data seem to suggest that factors other than defect morphology may influence treatment response to MINST.

Quantitative study on the propagation characteristics of MFL signals of outer surface defects in long-distance oil and gas pipelines

The magnetic flux leakage (MFL) internal detection is one of the most effective methods for assessment of long-distance oil and gas pipelines. To quantify the outer surface defect through MFL signals, which are affected by pipe wall and its shielding effect, propagation compensation factor (PCF) was proposed to apply to a classical magnetic charge model. Using the established model for outer surface defects in long-distance oil and gas pipelines, characteristics of MFL signals with different wall thicknesses and defect sizes along with their propagation patterns were analyzed. To verify the analytical model, X70 pipes with different wall thicknesses were used for systematic experiments. The results showed that the pipe wall thickness had a significant attenuation effect on the MFL signals of external defects. As the wall thickness increased from 7 to 17 mm, the MFL signals exhibited a first-order exponential decay, with a maximum error of 25.8% and a minimum error of 2.5%. When the defect depth increased from 0.6 to 7.2 mm, the MFL signals showed a first-order exponential upward trend, with a maximum error of 18.8% and a minimum error of 2.0%. This study effectively described the propagation characteristics of MFL signals of outer surface defects, and facilitated identification and quantitative evaluation of outer surface defects.

Reliability assessment of pipeline steel under corrosion defect

The assessment of the reliability index and /or the failure probability of the corroded pipeline was estimated. By comparing the results of the different standards and using the probabilistic approach, this paper provides a more accurate assessment of the reliability of the pipeline under corrosion defects. The probabilistic approach is carried out by confronting the results of the commonly used standards such as B31G, modified B31G, Batelle, DNV RP F101 and Shell, in order to know the more conservative technique and determine the reliability in which the burst pressure of the pipeline is controlled. The commonly used standards are coupled with the Rackwitz optimization algorithm, and the deterministic failure assessment diagram is coupled with the Monte Carlo simulation. The degradation models are used to assess the probability expressed by the index of reliability (β) through the dimensions of the defects based on the operating pressures. For instance, for a target reliability index value of 5.2, the pipeline API 5L X 52 work within safe condition for ASME B31G and modified ASME B31G models. In addition, at an operating pressure equal to 9 MPa, the safety defect depth is equal to 55% and 49% for the two codes respectively. When the operating pressure reach 13 MPa, the safety defect depth is equal to 39% and 38% for the two codes respectively. When the assessment is based on DNV RP F101 and Battelle methods, for a target reliability index value of 5.2, the two codes indicate that any value of the reliability index is higher than the target index up to the ratio d/t of 44% for a working pressure of 13 MPa. For the relative defect depth d/t = 60%, all the different pressures fall into the domain of failures (β < 3.72). The important reliability assessment results can manage maintenance and inspection strategies to ensure the safe and efficient operation of pipelines in the oil and gas industry.

Response Mechanisms of Additional Displacement Defects in Oxides to Ionization Damage in Bipolar Transistors

When evaluating the radiation damage of charged particles to bipolar junction transistors (BJTs), the additional displacement defects caused by charged particles in oxide cannot be ignored. In this paper, we demonstrate that the additional displacement defects can enhance or weaken the ionization damage level of BJTs. Additional displacement defects always weaken ionization damage in PNP BJTs and may enhance it in NPN BJTs. In addition, in the same BJTs, the response of additional displacement defects in oxide at different depths to ionization damage is also different, which strongly depends on the depth of additional displacement defects. Additional displacement defects in oxide show different results in response to ionization damage in different types of BJTs, which brings complexity to the accurate assessment of radiation hardness of BJTs. Therefore, in this paper, three different types of BJTs are analyzed in detail. In their oxides, the response mechanism of additional displacement defects to ionization damage is analyzed in detail, which provides a reference for improving the evaluation accuracy of more types of BJTs.

Influence of Top Seal Damage on Contact Seal in Ram Blowout Preventer.

Top seal failure of ram blowout preventer (BOP) is one of the main factors leading to well control risk. The constitutive model and parameters of nitrile butadiene rubber (NBR) were optimized by compression and tensile tests, and the failure analysis model of the contact seal of the ram BOP top seal was built. The nonlinear contact mechanical behavior of the connection part of the BOP top seal was analyzed by the finite element method. Then, the influence of corrosion and wear defects at the top seal position of the 2FZ35-70 BOP under rated working pressure on the contact seal were studied, and the results showed that the overall contact pressure distribution of the top seal corrosion defects was uniform, the local contact pressure of the corrosion pit edge increased, and the top contact pressure decreased. The overall contact pressure of the wear defect of the top seal decreased linearly, the contact pressure at the maximum depth of the wear defect was the smallest, and the contact pressure gradually decreased to both sides. Ultimately, to guarantee the safety and reliability of the ram BOP, it is suggested that the acceptable depths of the seal corrosion pit and the wear at the top of the ram BOP are 4.0 mm and 0.2 mm, respectively, thus the reliability evaluation problem of the quantitative seal of the ram BOP top seal is solved.

Study of a Compton backscattering wall defects detection device using the Monte Carlo method

Abstract In view of the shortcomings of traditional wall defect detection methods, such as small detection range, poor accuracy, non-portable device, and so on, a wall defects detection device based on Compton backscattering technology is designed by Monte Carlo method, which is mainly used to detect the size and location information of defects in concrete walls. It mainly consists of two parts, the source container and the detection system: first, through the simulation and analysis of the parameters such as the receiving angle of the backscattered particles and the rear collimating material of the detector, the influence of the fluorescent X-ray peak of the detector collimating material on the backscattered particle counts is eliminated and the detected error is reduced; second, the ring array detector design, compared with single array detector and surface array detector, can facilitate real-time detection of defect orientation, expanding the single scan range and improving the detection efficiency. After simulation and comparative analysis, the relevant optimal parameters are obtained: the object is detected using a Cs-137 γ-ray source with an activity of 6 mCi, and a ring detector consisting of four 0.5-inch cube-shaped CsI scintillator detectors is placed at 150° to receive the backscattered photons. The simulation analysis using the Monte Carlo FLUKA program showed that the maximum depth of wall defect detection is 8 cm, the maximum error fluctuation range of defect depth and thickness is ±1 cm, the overall device weight is &lt;20 kg, and the measurement time is &lt;5 min.

Effect of Osteontm Ii Collagen in The Treatment of Chronic Periodontitis Patients: A Clinical And Radiographical Study

inflammatory disease that lasts for a long time and affects the soft and hard tissues around the teeth. The ultimate goal of periodontal therapy is to regenerate the lost periodontal tissue for optimal function and aesthetics. The aim of this study was to evaluate the clinical and radiographic effects of OsteonTM II collagen, in comparison with open flap debridement (OFD) in the treatment of chronic periodontitis patients. Material and methods: 30 periodontal bony defects in 7 systemically healthy patients that had at least 3 defects, within the age range of 25–40 years, viewing moderate to severe chronic periodontitis were selected and randomly divided into two groups, control group(n=15) was treated by open flap debridement (OFD) alone and test group(n=15) was treated by OFD with placement of OsteonTM II Collagen. All the selected periodontal defects were evaluated with the clinical and radiographic parameters such as plaque index (PI), gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL), and radiographic defect depth. All the clinical and radiographic parameter values attained at (baseline and 6 months) were subjected to statistical analysis. Results: Significant lessening in PI, GI, PPD, CAL and radiographic defect depth were detected after 6 months of periodontal surgery as compared to baseline in both groups (P&lt;0.05). Superior decrease in PPD, gain in CAL and radiographic defect fill was seen in test group after 6 months. Conclusion: In terms of reducing probing pocket depth (PPD), increasing clinical attachment level (CAL), and filling bone defects, OsteonTM II collagen showed significant clinical, radiographic, and statistical improvements compared to open flap debridement (OFD) alone

Study of the effect of hole defects on wood heat transfer based on infrared thermography

From a quantitative perspective using infrared thermography, this study examines the impact of various surface defect sizes on the heat transfer of wood under the condition of wood along-grain excitation. Firstly, the correlation between the defect size and the temperature change ΔT in the thermal steady state phase and the cooling coefficient Ve in the unsteady state phase were built by theory analyzed. And then, a theoretical analysis conducted under wood along-grain excitation conditions examines the theoretical relationship between the diameter D and depth H of the hole defect and the two thermodynamic properties ΔT and Ve. Second, using larch (Larix gmelinii) as the study's object, thermal excitation experiments and natural cooling experiments were conducted on wood specimens in the down-grain direction. The temperature field changes on the specimens' surfaces were recorded using a thermal imaging camera in order to obtain ΔT and Ve for various hole defect sizes. Then, using finite element modeling, the prediction models of ΔT and Ve are built, respectively, for the case of hole defects of various sizes. The model demonstrates that: A very strong negative correlation between the defect diameter D and the thermal steady-state temperature change ΔT (R2 > 0.946) and a very strong positive correlation with the cooling coefficient Ve (R2 > 0.985); The defect depth H has an extremely strong positive correlation with Ve (R2 > 0.946). In addition, as H increases ΔT increases first and then decreases, which is in line with the quadratic curve distribution (R2 > 0.991). Finally, the prediction model was compared with the experimental data for validation. The validation results revealed that the established model's ΔT was similar to the experimental ΔT variation pattern (R2 = 0.864) and that it was able to more accurately predict the pattern and value of Ve (R2 = 0.846, MAPE = 5.44%). The research results could lay some preliminary theoretical foundation for the formation of wood defect nondestructive testing technology based on infrared thermography.

Guided Wave Tomography of Surface Defects Based on the Method of Moments

AbstractThe detection and evaluation of corrosion, cracks, flaws, and other imperfections in aged structures are critical for enhancing safety and evaluating residual service life in structural health monitoring (SHM) and nondestructive testing (NDT). A guided wave tomography based on the method of moments (MOM) for exact detection of the surface defects in plates, including their profile, size, and position is proposed in this paper. The mathematical relationship between the plate thickness and the objective function is derived theoretically for the A0 mode. Based on the obtained relationship, a plate thickness imaging technique is proposed. The efficiency of the proposed technique is confirmed by the results of numerical simulation and experimental data. Center and off‐center surface defects are considered. 64 probes are evenly distributed in a circle outside the defect to capture omnidirectional wave signals. Both numerical and experimental results demonstrate that the guided wave tomography proposed can effectively reconstruct the spatial plate thickness distribution, enabling the precise identification of the defect's shape, depth, and position. The qualitative analysis and quantitative data provide effective guidance for NDT or SHM technologies in engineering.

Long-term stability of infrabony defects treated with enamel matrix derivative alone: A retrospective two-centre cohort study.

To assess the long-term stability of attachment gain in infrabony defects (IBDs) 10 years after regenerative treatment with an enamel matrix derivative (EMD) alone. Two centres (Frankfurt [F] and Heidelberg [HD]) invited patients for re-examination 120 ± 12 months after regenerative therapy. Re-examination included clinical examination (periodontal probing depths (PPD), vertical clinical attachment level (CAL), plaque index (PlI), gingival index (GI), plaque control record, gingival bleeding index and periodontal risk assessment) and review of patient charts (number of supportive periodontal care [SPC] visits). Both centres included 52 patients (29 female; median baseline age: 52.0 years; lower/upper quartile: 45.0/58.8 years; eight smokers), each contributing one IBD. Nine teeth were lost. For the remaining 43 teeth, regenerative therapy showed significant CAL gain after 1 year (3.0; 2.0/4.4 mm; p < .001) and 10 years (3.0; 1.5/4.1 mm; p < .001) during which CAL remained stable (-0.5; -1.0/1.0 mm; p = 1.000) after an average SPC of 9 years. Mixed-model regression analyses revealed a positive association of CAL gain from 1 to 10 years with CAL 12 months post operation (logistic: p = .01) as well as a higher probability for CAL loss with an increasing vertical extent of a three-walled defect component (linear: p = .008). Cox proportional hazard analysis showed a positive association between PlI after 12 months and tooth loss (p = .046). Regenerative therapy of IBDs showed stable results over 9 years. CAL gain is associated with CAL after 12 months and decreasing initial defect depth in a three-walled defect morphology. Tooth loss is associated with PlI 12 months post operation. DRKS00021148 (URL: https://drks.de).

Defect Detection and Depth Estimation in Composite Materials for Pulsed Thermography Images by Nonuniform Heating Correction and Oriented Gradient Information.

Pulsed thermography is a nondestructive method commonly used to explore anomalies in composite materials. This paper presents a procedure for the automated detection of defects in thermal images of composite materials obtained with pulsed thermography experiments. The proposed methodology is simple and novel as it is reliable in low-contrast and nonuniform heating conditions and does not require data preprocessing. Nonuniform heating correction and the gradient direction information combined with a local and global segmentation phase are used to analyze carbon fiber-reinforced plastic (CFRP) thermal images with Teflon inserts with different length/depth ratios. Additionally, a comparison between the actual depths and estimated depths of detected defects is performed. The performance of the nonuniform heating correction proposed method is superior to that obtained on the same CFRP sample analyzed with a deep learning algorithm and the background thermal compensation by filtering strategy.

Impact of the correlation between random variables on the reliability assessment of the corroded pipelines

In the present work, an Algerian pipeline made of API X70 steel, used for transporting gas and subjected to corrosion attack for three decades, was investigated. Using an intelligent inspection tool, the sizes and orientations of the defects were determined to analyze and improve the accuracy of reliability and/or probability of failure estimates for the damaged pipelines. A probabilistic methodology has been developed to assess the reliability index and the sensitivity of each random variable, within the limit state function, of a gas-transporting steel pipeline that has been corroded for three decades. The reliability analysis utilizes the Second Order Reliability Method, which is based on the BFGS algorithm. In addition, the corrosion defect depth, pipe wall thickness, and corrosion defect length are the most dominant variables within the limit state function, followed by ultimate stress and operating pressure, respectively. Meanwhile, for a failure scenario, thus, it is essential to include a potential parameter such as the correlation coefficient between random variables within the objective function during reliability assessment. For instance, not taking into account the correlation between random variables can lead to an overestimation of the reliability index by 8.89% for a defect depth to wall thickness ratio d/t of 20%. This overestimation increases to 19.16% when the d/t ratio increases to 70%. If the correlation coefficient is significant, it can cause an increase of 8.86% in the error of reliability index assessment for a defect with a depth to wall thickness ratio of 20%, and an increase of 14.58% for a defect with a ratio of 50%. Besides, these avoid the conservative practice resulting from the negligence of the existing correlation between random variables within the limit state function. Hence, considering the correlation coefficients during reliability assessment contributes to setting optimal maintenance schedules for pipelines made of steel under localized corrosion attack.

Injectable platelet-rich fibrin with demineralized freeze-dried bone allograft compared to demineralized freeze-dried bone allograft in intrabony defects of patients with stage-III periodontitis: a randomized controlled clinical trial

AimThe current randomized controlled clinical trial assessed the effect of injectable platelet-rich fibrin (I-PRF) combined with demineralized freeze-dried bone allograft (DFDBA) compared to DFDBA alone in the management of intrabony defects of stage-III periodontitis patients.MethodologyFollowing sample size calculation, twenty stage-III periodontitis patients with ≥ 5 mm clinical attachment level (CAL)-loss and ≥ 3 mm intrabony defects were randomized into test (I-PRF + DFDBA; n = 10) and control (DFDBA; n = 10) groups. CAL (primary outcome), periodontal probing depth (PPD), gingival recession depth (GRD), full-mouth plaque scores (FMPS), full-mouth bleeding scores (FMBS), radiographic linear defect depth (RLDD), and bone fill (secondary outcomes) were examined at baseline, 3, 6, and 9 months post-surgically.ResultsI-PRF + DFDBA and DFDBA independently demonstrated significant intragroup CAL-gain, PPD-, and RLDD-reduction at 3, 6, and 9 months (p < 0.05), with no significant intergroup differences observed (p > 0.05). CAL-gain (mean ± SD) of 2.40 ± 0.70 mm and 2.50 ± 0.85 mm and PPD-reduction of 3.50 ± 1.18 mm and 2.80 ± 0.42 mm were demonstrated for I-PRF + DFDBA and DFDBA at 9 months respectively. Both groups showed significant intragroup RLDD improvement, with a RLDD of 3.58 ± 0.66 mm and 3.89 ± 1.57 mm for I-PRF + DFDBA and DFDBA at 9 months respectively. Stepwise linear regression analysis revealed that baseline RLDD and bone fill at 9 months were significant predictors of CAL (p < 0.05).ConclusionWithin the present study’s limitations, DFDBA with or without I-PRF resulted in significant improvement in clinical and radiographic periodontal parameters in the surgical treatment of periodontal intrabony defects of stage-III periodontitis patients. Addition of I-PRF to DFDBA does not appear to significantly enhance the DFDBA’s reparative/regenerative outcomes.Clinical relevanceWithin the current study’s limitations, routinely adding I-PRF to DFDBA cannot be recommended to significantly improve DFDBA’s treatment outcomes in intrabony defects.

A new insight into the mechanism of persistent luminescence phosphors SrS: Eu2+, Pr3+

The red persistent luminescence phosphors SrS: , (x = 0∼0.001, y = 0∼0.003) were synthesized by the solid-state reaction method in a weak reducing atmosphere of active carbon. The synthetic parameters, photoluminescence characteristics, and dynamic properties of thermoluminescence of the phosphors were studied systematically. According to the results of photoluminescence spectra of SrS: , , the energy level scheme of the phosphors was confirmed quantitatively. Based on the studies of the scanning electron microscope (SEM), UV-Visible absorbance spectra, afterglow decay curves, thermoluminescence(TL) spectra, and X-ray photoelectron spectroscopy (XPS) spectra, we found that the SrS: , (SSEP) phosphor presented the best persistent luminescence property, which mainly resulted from its outstanding absorbance characteristic, deeper depth of () defects, and fewer defect concentration belonging to the higher-order kinetics. Those comprehensive results deduced that a complex defect ()- should present in the Eu2+ doping phosphors, and the Pr3+ doping will produce defects, which can suppress the formation of () defects and increase their energy depth.

Failure Pressure Prediction of Corroded High-Strength Steel Pipe Elbow Subjected to Combined Loadings Using Artificial Neural Network

There is no reliable failure pressure assessment method for pipe elbows, specifically those subjected to internal pressure and axial compressive stress, other than time-consuming numerical methods, which are impractical in time-critical situations. This paper proposes a set of empirical equations, based on Artificial Neural Networks, for the failure pressure prediction of pipe elbows subjected to combined loadings. The neural network was trained with data generated using the Finite Element Method. A parametric analysis was then carried out to study the failure behaviour of corroded high-strength steel subjected to combined loadings. It was found that defect depth, length, spacing (longitudinal), and axial compressive stress greatly influenced the failure pressure of a corroded pipe elbow, especially for defects located at the intrados, with reductions in failure pressure ranging from 12.56–78.3%. On the contrary, the effects of circumferential defect spacing were insignificant, with a maximum of 6.78% reduction in the failure pressure of the pipe elbow. This study enables the failure pressure prediction of corroded pipe elbows subjected to combined loadings using empirical equations. However, its application is limited to single, longitudinally interacting, and circumferentially interacting defects with the specified range of parameters mentioned in this study.

Pipeline condition assessment and finite element modeling of mechano-electrochemical interaction between corrosion defects with varied orientations on pipelines

Multiple corrosion defects located in varied orientations are common on pipelines, significantly impacting pipeline conditions. In this work, 3D finite element (FE) based multi-physics field coupling models were developed to model mechano-electrochemical (M−E) interaction between corrosion defects with varied orientations and its effect on pipeline conditions. The effects of the parameters, including defect geometries, operating conditions, and the relative positions and spacings between the defects, were determined. The results demonstrated that, the strongest M−E interaction occurred between defects when the longitudinal or circumferential spacing is 0, causing high-level local stress concentration and the anodic current density (i.e., corrosion rate) at the corrosion defects. As the defects gradually overlapped or separated from each other on the pipe surface, the magnitude of the M−E interaction decreased. The interaction between defects even disappeared when the longitudinal or circumferential spacing between defects reached 96 mm or 72 mm, respectively, and the defects can be assessed separately. An increased internal pressure led to local plasticity deformation and anodic current density concentration occurring at the inner edge of the defects and defect adjacent area. For example, the maximum anodic current density increased by 56.4% when the internal pressure increased from 12 MPa to 17 MPa. It was also observed that M−E interaction between defects disappeared if the defects were shorter than 48 mm or shallower than 8 mm. Sensitivity analysis demonstrated that the degree of M−E interaction was most sensitive to circumferential spacing, followed by defect depth, defect length, longitudinal spacing, and internal pressure.

The evolution of the out-of-phase dipole beams in the repulsive defect photonic moiré lattice with saturable self-focusing nonlinearity media

We demonstrate in a numerical manner the intriguing transmission of the out-of-phase (OOP) dipole beams in the repulsive defect photonic moiré lattice with rotation angle and defect depth under saturable self-focusing nonlinearity. Photonic moiré lattices, that are created by two mutually rotated square patterns with a relative rotation angle . We introduce a single-site repulsive defect in periodic photonic moiré lattices, and excite this site with the OOP dipole beams. We reveal that the OOP dipole beams undergoes two evolution stages during propagation, for the first time to our knowledge. It is shown that the OOP dipole beams maintain stable propagation over a certain distance in the first stage, which depends on the defect depth. Then the energy of the OOP dipole beams flows between its two spots, exhibiting periodic-like oscillation in the second stage, along with discussion about the effect of defect depth on the stable propagation distance of the OOP dipole beams, one finds that the stable propagation distance decreases linearly with increasing defect depth . At the same time, we perform a polynomial fit between the oscillation period of the OOP dipole beams and the defect depth . These two fitting curves fully demonstrate that the repulsive defect can profoundly affect the propagation behavior of the OOP dipole beams. Our results may provide novel insights into the localization and oscillation of beams in defect structures.

Residual strength prediction of X80 steel pipelines containing group corrosion defects

As subsea oil and gas pipelines are corroded by moisture, soil, and other external factors, their surfaces develop groups of corrosion defects, which are prone to stress concentration and affect the residual strength of the pipeline. To this end, a finite element (FE) model of an X80 pipeline containing group corrosion defects is established here using ABAQUS. Considering the influence of various defect sizes on the residual strength of the pipe, 46 sets of failure data for group corrosion pipes with different geometries and 364 sets of maximum von Mises stresses versus internal pressure for different operating conditions were obtained. The accuracy of the FE model was verified using burst tests. The residual strength prediction model of the pipes was obtained by 1stopt software. The results show that the key factor affecting the residual strength of pipes containing group corrosion defects is the depth of the deepest defect and the strength of the interaction between the group corrosion defects. Based on the DNVRP-F101 standard, a more accurate method for calculating the failure pressure of group corrosion pipes was obtained by introducing correction factors. The results of this study can provide theoretical support for the safe management of group corrosion X80 pipelines.

Fournier’s gangrene reconstruction: A 10-year retrospective analysis of practice at Guys and St Thomas’s NHS Foundation Trust

Fournier's gangrene is a rare and potentially fatal condition that affects the external genitalia and perineum as a necrotizing soft-tissue infection. It is equally prevalent in men and women and although there are many ways to manage the condition, it must be done so effectively because there is a chance that life-threatening complications could develop. This retrospective study set out to fill any knowledge gaps, compare reconstructive options to those described in the literature, and promote reflection on current management. Between January 2010 and January 2020, all perineal debridement operation notes were examined. The primary conclusions were that a large majority of defects could be repaired using split skin grafts to reduce surgical time and donor site morbidity. To avoid secondary contracture and the need for revision surgery, full-thickness skin grafts should be used whenever possible to treat penile defects.