Rupture Time Research Articles

Instability and rupture of surfactant-laden bilayer thin liquid films.

The stability of surfactant-laden bilayer thin films, where the top layer is subject to van der Waals driven breakup, is of particular relevance to applications where one thin liquid layer is spread on another, such as film-forming firefighting foams and multilayer coatings. Although there has been much prior modeling work on the stability of thin liquid bilayers, additional physical effects and assumptions were incorporated in those studies, making it difficult to isolate the influence of surfactant on the rupture of the top layer. The present work addresses this issue through application of the lubrication approximation to derive a coupled system of nonlinear evolution equations describing the perturbations to the liquid-liquid and liquid-air interfaces and the surfactant interfacial concentrations. The surfactant is assumed to be insoluble and can be present at each interface. Linear stability analysis suggests, and nonlinear simulations confirm, that by using surfactant that adsorbs to both interfaces, the rupture time can be increased by an order of magnitude relative to the surfactant-free case. However, we find it crucial to have the right amount of surfactant to generate strongly stabilizing Marangoni stresses without reducing the interfacial tension too much. Nonlinear simulations and linear stability analysis provide insight into the mechanisms of the delayed rupture and show how the direction and strength of the Marangoni stresses strongly depend on the viscosity ratio of the layers. These results can help guide the choice and design of surfactants to achieve more effective firefighting foams and more stable liquid coatings.

Elective induction of labor following prior cesarean delivery

Following the ARRIVE trial, induction of labor at 39 weeks has increased in the United States. The risk of uterine rupture and optimal timing of elective induction in those women with a prior cesarean delivery is not well described, and they were not included in the ARRIVE trial. We aimed to estimate the risk of uterine rupture in those women undergoing elective induction of labor with a prior cesarean delivery. This was a retrospective cohort of women with a prior cesarean delivery from 1996 to 2000. Women were included if they had ≤ 2 prior cesareans. Women were excluded if they had a history of an unknown prior incision, a classical incision, gestational age < 39 weeks, any diabetes, chronic hypertension, twin gestation, collagen or vascular disease, or HIV. Those undergoing expectant management were compared to those undergoing elective induction with no medical or obstetrical indications for delivery. Analysis was performed at three gestational age groups: 39 weeks, 40 weeks, and 41 weeks. The primary outcome was uterine rupture. Secondary outcomes included vaginal delivery and a composite major morbidity. Comparisons were made using Student’s t-test or χ2 test as appropriate. At 39 weeks, 618 (10.3%) elective inductions were compared to 5365 (89.7%) undergoing expectant management; uterine rupture occurred more frequently (2.1% vs. 0.9%; P=0.006) with fewer successful VBAC (66.8% vs. 75%; P< 0.001). The risk of uterine rupture was similar between groups at 40 (0.8% vs. 1.2%; P=0.387) and 41 weeks (1.4% vs. 0.8%; P=0.448). Among elective inductions, the risk of rupture or major morbidity was not significantly different by timing, although 39 weeks was associated with more vaginal deliveries. Women undergoing elective induction of labor with a prior cesarean scar had an increased risk of uterine rupture when compared to expectant management at 39 weeks, with fewer successful VBAC. However, when induction is compared across all age groups, the risk of a major maternal morbidity is not increased.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

A study on risk factors and outcome in prelabour rupture of membrane

Background and Objectives: During the last three decades it has taken a new dimension because of identification of clinical risk factors and improved fetomaternal outcome due to better management. The present study aimed to assess the maternal and fetal outcome in patients with prelabour rupture of membrane. Methods: The present prospective cross-sectional study was conducted among the patients presenting with spontaneous rupture of membrane, admitted in Department of OBG of Al-Ameen Medical College Medical College, Athani road, Vijayapura. Informed consent was taken from all enrolled patients after detailed counselling. The contents of the consent were read out to the patients in his language. Detailed history taking including age, parity, weight gain, inter pregnancy interval. History emphasized on exact time of rupture of membrane and duration the amount of leak. Detailed examination like blood pressure, height, temperature was noted. In obstetric history uterine height, fetal presentation, fetal heart rate, estimated weight and other parameters of maternal and fetalwell-being was noted. A sterile speculum examination was conducted and presence of liquor amini was noted. The maternal and fetal outcome were monitored and recorded in the Performa. All the data were entered in excel sheet and the analysis was performed using SPSS V.21.0 operating on windows 10. Results: Present study total of 100 patients fulfilling inclusion criteria are included in present study after obtaining the informed consent. The mean age of the patients was found to be 24.92. The maternal complications seen among patients were with 34% puerperal fever, followed with 10% with wound infections and 3% with UTI. Among the fetal complications, the study documented majority with presence of respiratory distress syndrome in 17% of the newborn, followed with 4% meconium aspiration, 3% with conjunctivitis and 1% with sepsis and still birth. Conclusion: The present study documented the major etiological factors for PROM among study participants was following the coitus, followed with history of previous pregnancy leaking. The study also documented the common mode of delivery was lower segment caesarean section with cause of failure to progress among them. The maternal complication documented was majority with puerperal fever and wound infection. The newborn complication documented was majority with respiratory distress syndrome followed with meconium aspiration.

Creep Rupture Strength and Phase Stability of the Austenite Phase for KA-SUS304J1HTB

Metallurgical factor causing the heat-to-heat variation in creep rupture strength have been investigated for KA-SUS304J1HTB. In the long-term, there was a maximum difference of 3.5 times in creep rupture time between the heat with low creep strength and the heat with high creep strength. In the heat with low creep rupture strength, most of the creep voids occurred at the matrix/σ phase interface. Moreover, in the heat with low creep rupture strength, the area fraction of σ phase was larger than in the heat with high creep rupture strength. Considering that the difference in the area fraction of σ phase in each heat is related to the difference in phase stability of the austenite phase, the Md value in each heat was evaluated. The Md value is the parameter correlated with phase stability. The creep rupture time of each heat was correlated with the Md value. The smaller the Md value, the longer the creep rupture time. Therefore, the heat-to-heat variation in creep rupture strength is caused by the difference in the phase stability of each heat. In other words, in the heats with low phase stability, creep rupture strength is low because a large amount of σ phase precipitates during the creep test.

Evaluating the Efficacy of Polyglycolic Acid-Loading Tetrandrine Nanoparticles in the Treatment of Dry Eye

Introduction: Dry eye disease (DED) is a multifactor-induced disease accompanied by increased osmolarity of the tear film and inflammation of the ocular surface. Traditional anti-inflammation agent corticosteroids applied in DED treatment could result in high intraocular pressure, especially in long-term treatment. Therefore, we explored a nano drug that aimed to block the formation pathway of DED which had anti-inflammatory, sustained release, and good biocompatibility characteristics in this study. Methods: We prepared a novel nanomedicine (Tet-ATS@PLGA) by the thin film dispersion-hydration ultrasonic method and detected its nanostructure, particle size, and zeta potential. Flow cytometry was used to detect the cell survival rate of each group after 24 h of drug treatment on inflammed Statens Seruminstitut Rabbit Corneal (SIRC) cells. Observed and recorded corneal epithelial staining, tear film rupture time, and Schirmer test to detect tear secretion on the ocular surface of rabbits. The corneal epithelial thickness, morphology, and number of bulbar conjunctival goblet cells were recorded by H&E staining. Finally, we detected the expression of VEGF, IL-1β, PGE2, and TNF-α by cellular immunofluorescence staining and enzyme-linked immunosorbent assay (ELISA). Results: The encapsulation efficiency and drug loading of Tet-ATS@PLGA were 79.85% and 32.47%, respectively. At eye surface temperature, Tet can easily release from Tet-ATS@PLGA while that it was difficult to release at storage temperature and room temperature. After 2 weeks medication, Tet-ATS@PLGA can effectively improve the tear film rupture time and tear secretion time in a DED model (p <0.05). Compared with the normal group (62.34 ± 4.86 mm), the thickness of corneal epithelium in ATS (29.47 ± 3.21 mm), Tet-ATS (46.23 ± 2.87 mm), and Tet-ATS@PLGA (55.76 ± 3.95 mm) gradually increased. Furthermore, the flow cytometry indicated that Tet-ATS@PLGA can effectively promote the apoptosis of inflammatory SIRC cells, and the cellular immunofluorescence and ELISA experiments showed that the expression intensity of inflammatory factors such as VEGF, IL-1β, PGE2, and TNF-α decreased in this process. Interestingly, Tet also had the effect of reducing intraocular pressure. Conclusion: Tet-ATS@PLGA can effectively promote the apoptosis of inflammatory corneal epithelial cells, thus inhibiting the expression of inflammatory factors to block the formation of DED and improve the secretion of tear on the ocular surface.

Real‐Time Seismogeodetic Earthquake Magnitude Estimates for Local Tsunami Warnings

AbstractWe estimate a seismogeodetic earthquake moment magnitude using unclipped, broadband velocity and displacement waveforms from collocated Global Navigation Satellite Systems and seismic stations located within 800 km epicentral distance for nine 7.2 &lt; &lt; 9.1 earthquakes. We consider the vertical component of seismogeodetic displacement as an approximate source time function and integrate the associated time series to obtain the seismic moment. By continuing to integrate vertical displacement beyond the initial P‐waves, we obtain rapid estimates of that are within 0.2 magnitude units for 8 thrust faulting events and within 0.3 units for the single normal faulting event. Because our estimates of the seismic moment are based on the maximum value of integrated displacement, no regression against other source parameters, or distance, is necessary. Our new method shows promise for integration into earthquake and local tsunami early warning systems, including tsunami earthquakes characterized by relatively slow moment release over a longer rupture time, and earthquakes with complex source time functions.

Effects of Heat Treatment on the Microstructure and Properties of a Cast Nickel-Based High-Cr Superalloy

The effect of solution treatment and intermediate heat treatment on the microstructure and properties of a new cast nickel-based high-Cr superalloy was investigated in this paper. The results indicate that the tensile strength and elongation at 900 °C increase when the solution temperature increases from 1160 °C to 1180 °C and then decrease when the solution temperature changes from 1180 °C to 1200 °C and 1220 °C. The stress rupture test results of the high-Cr superalloy under conditions of 900 °C/275 MPa shows that the rupture time, elongation, and reduction of area initially increased and then decreased with the increase in solution treatment temperatures. The results of stress rupture tests for the alloy after intermediate heat treatment followed by furnace-cooling, air-cooling, and water-cooling show that the morphology and distribution of γ’ phase have a great influence on the tensile test results at 900 °C of the alloy but no obvious influence on the test at 900 °C/275 MPa. The microstructure analysis of the superalloy after heat treatment shows that: when the solution treatment temperatures are at 1200 °C and 1220 °C, the incipient melting appears in the interdendritic region, which can severely deteriorate mechanical properties; the morphology of γ′ phase changes gradually from cube to spherical; and a large number of fine γ’ phase precipitates in the γ channel are found with increasing cooling rate after intermediate heat treatment.

Application of soft constrained machine learning algorithms for creep rupture prediction of an austenitic heat resistant steel Sanicro 25

Creep rupture extrapolation is crucial for high-temperature materials served in power plants. Many analytical models can be used for creep rupture analysis, and fundamental models are also available. Machine learning is also an alternative. However, unphysical prediction curves occur readily in common machine learning algorithms, where one must manipulate the best results or ignore the less satisfactory ones. Using just high regression coefficients and low errors is not enough to obtain high accuracy of the methods. Nevertheless, five soft constrained machine learning algorithms (SCMLAs), where soft constraints, stability analysis by culling long-time or low-stress data, extrapolation from short to long times, and errors of solutions and algorithms are considered, are used for creep rupture prediction in this work. The models can generate reasonable results for fitting all data, extrapolating from short to long times, and stability analysis for Sanicro 25 after a number of tests. The errors of solutions for all the analyses are in a quite reasonable range, including extrapolation and stability analysis. The average relative standard deviation of the five SCMLAs is less than 2.5% at three times the maximum experimental creep rupture time. Creep rupture strength of the austenitic stainless steel Sanicro 25 can be predicted quantitatively by taking the average predicted stresses of the five SCMLAs. The method can also be used for other high-temperature alloys with similar creep degradation mechanisms.

Effect of sodium hyaluronate eye drops combined with tobramycin, dexamethasone and pranoprofen eye drops in the treatment of dry eye after phacoemulsification.

To investigate the clinical effect of sodium hyaluronate eye drops combined with tobramycin, dexamethasone, and pranoprofen eye drops in the treatment of dry eye after phacoemulsification. Medical records of 188 patients with dry eye after phacoemulsification, treated in our hospital from August 2020 to August 2021, were included and divided into groups based on the type of dry eye treatment. Patients in the control group (n = 90) were treated with tobramycin, dexamethasone, and pranoprofen eye drops. Patients in the test group (n = 98) were treated with sodium hyaluronate, tobramycin, dexamethasone, and pranoprofen eye drops. The tear secretion test (TST), film rupture time (BUT), corneal fluorescence staining (FS) score, levels of interleukin (IL)-6, and tumor necrosis factor (TNF)-α before the treatment and at 1 month follow-up, the overall total effective rate and the number of completely cured cases were compared between the two groups. Multiple linear regression was used to calculate coefficients for predicting clinical variables. Ordinal logistic regression was used to compute coefficients and odds ratios for predicting effective scores. The total effective rate in the observation group (99%) was significantly higher than that in the control group (80.00%). After the treatment, the TST and BUT indexes of the observation group were higher compared to the control group, and the FS score of the observation group was lower than that of the control group. TNF-α and IL-6 levels of the observation group were lower compared to the control group. Logistic regression analysis demonstrated that the differences in the effective rate and clinical variables between the two groups remained significant after adjusting for the effect of age. A combination of sodium hyaluronate, tobramycin, dexamethasone, and pranoprofen eye drops for the treatment of dry eye after phacoemulsification can improve the curative effect, reduce corneal fluorescein staining and inflammatory factor index levels compared to the treatment regimen lacking sodium hyaluronate eye drops.

The Predicted Position of the Knee Near the Time of ACL Rupture Is Similar Between 2 Commonly Observed Patterns of Bone Bruising on MRI

Background: Bone bruises observed on magnetic resonance imaging (MRI) can provide insight into the mechanisms of noncontact anterior cruciate ligament (ACL) injury. However, it remains unclear whether the position of the knee near the time of injury differs between patients evaluated with different patterns of bone bruising, particularly with regard to valgus angles. Hypothesis: The position of the knee near the time of injury is similar between patients evaluated with 2 commonly occurring patterns of bone bruising. Study Design: Descriptive laboratory study. Methods: Clinical T2- and T1-weighted MRI scans obtained within 6 weeks of noncontact ACL rupture were reviewed. Patients had either 3 (n = 20) or 4 (n = 30) bone bruises. Patients in the 4–bone bruise group had bruising of the medial and lateral compartments of the femur and tibia, whereas patients in the 3–bone bruise group did not have a bruise on the medial femoral condyle. The outer contours of the bones and associated bruises were segmented from the MRI scans and used to create 3-dimensional surface models. For each patient, the position of the knee near the time of injury was predicted by moving the tibial model relative to the femoral model to maximize the overlap of the tibiofemoral bone bruises. Logistic regressions (adjusted for sex, age, and presence of medial collateral ligament injury) were used to assess relationships between predicted injury position (quantified in terms of knee flexion angle, valgus angle, internal rotation angle, and anterior tibial translation) and bone bruise group. Results: The predicted injury position for patients in both groups involved a flexion angle <20°, anterior translation >20 mm, valgus angle <10°, and internal rotation angle <10°. The injury position for the 3–bone bruise group involved less flexion (odds ratio [OR], 0.914; 95% CI, 0.846-0.987; P = .02) and internal rotation (OR, 0.832; 95% CI, 0.739-0.937; P = .002) as compared with patients with 4 bone bruises. Conclusion: The predicted position of injury for patients displaying both 3 and 4 bone bruises involved substantial anterior tibial translation (>20 mm), with the knee in a straight position in both the sagittal (<20°) and the coronal (<10°) planes. Clinical Relevance: Landing on a straight knee with subsequent anterior tibial translation is a potential mechanism of noncontact ACL injury.

A novel damage constitutive model for creep deformation and damage evolution prediction

AbstractIn order to accurately predict creep deformation and damage evolution of nickel‐based superalloy GH4169, a novel damage constitutive model, that is, TTC CDM‐based model, was proposed based on TTC relations and continuum damage mechanics (CDM). This model combined the best features of the TTC relations and CDM. The recently developed TTC relations were intrinsic relations between threshold stress, tensile properties, and creep behavior and exhibited better prediction ability than Wilshire equations. It was determined that the model accurately predicted the minimum creep rate, rupture time, creep deformation, and damage evolution process of GH4169. Microstructural study has revealed that the creep fracture mode gradually converts from intergranular brittle fracture to transgranular ductile fracture as the stress decreases. Furthermore, the nonlinear creep damage accumulation effect was also revealed by the novel model.

Acupuncture Alleviates Corneal Inflammation in New Zealand White Rabbits with Dry Eye Diseases by Regulating α7nAChR and NF-κB Signaling Pathway.

The purpose of this study is to determine the mechanism of improvement in dry eye diseases (DEDs) treated by acupuncture. The inflammatory molecules and related pathways will be analyzed in our study. In order to establish the animal model for DEDs, healthy New Zealand white rabbits were treated with scopolamine (Scop) hydrobromide for 21 consecutive days. After 21 days, acupuncture, fluorometholone (Flu), and α7nAChR antagonist (α-BGT) treatments were performed, and the Scop injections were continued until day 35. The therapeutic effect of acupuncture on DED inflammation was evaluated by corneal fluorescence staining, tear film rupture time, tear flow measurement, in vivo confocal microscopy (IVCM), corneal histopathology, and cytokine protein chip technology. The influence of acupuncture on the corneal pathology and inflammatory factors ACh, α7nAChR, and NF-κB was detected by enzyme-linked immunosorbent assay (ELISA) and western blot. Compared with the group Scop, acupuncture can significantly reduce corneal staining and increase the tear film rupture time and tear flow, which are accompanied by a decrease in corneal epithelial detachment and lymphocyte infiltration. Acupuncture can relieve the inflammation of corneal stroma and mitigate the expression of proinflammatory factors and chemokines. Acupuncture can upregulate the expression of ACh and α7nAChR and downregulate the expression of NF-κB. Our findings demonstrate that acupuncture can alleviate corneal inflammation in New Zealand white rabbits with DEDs via α7nAChR and NF-κB signaling pathway regulation. The expression indicates that α7nAChR/NF-κB signaling pathway may be active and that acupuncture is a potential therapeutic target for dry eye.

Anisotropy and variability in thermal creep behaviour of Zr-2.5Nb pressure tube

The Zr-2.5Nb alloy pressure tubes of Indian Pressurized Heavy Water Reactors were manufactured from double melted ingots initially and subsequently from quadruple melted ingots to reduce impurities such as chlorine, phosphorus and carbon. In the current investigation, creep tests were carried out in the stress range of 0.7–0.9 times the yield strength and the temperature range of 350 °C–450 °C to characterize the thermal creep behaviour of Zr-2.5Nb alloy pressure tubes fabricated from double and quadruple melted ingots. The rupture time, minimum creep rate, stress exponent, activation energy and threshold stresses were obtained by carrying out the creep tests of the samples fabricated with their axis parallel to the axial and transverse directions of the pressure tubes. Experimental analysis revealed that the rupture time for double melted tube was 2–3 times lower than that of quadruple melted tubes, whereas no significant change in minimum creep rate was observed. Stress exponent values were obtained in the range of 3–5 signifying dislocation creep as the dominant creep mechanism. To predict the long-term creep properties, the master curves employing the Larson-Miller and Monkman-Grant methods were also evaluated. The effect of microstructural anisotropy, alloying elements and impurities on the thermal creep behaviour of Zr-2.5Nb pressure tube has been investigated.

A physics-based life prediction model of HP40Nb heat-resistant alloy in a coupled creep-carburisation environment

This paper reports the development of a physics-based life prediction model that incorporates three micro-damage processes. Both the particle area fraction and size, as determined using scanning electron microscopy, are used as the model input to predict the precipitate coarsening damage. Moreover, the carbon concentration profile, as measured using electron probe micro-analyser, are used to derive the carburisation damage distribution index. Compared to the Kowalewski-Dyson model, the present model can predict the stress dependent creep fracture strain and rupture time. The model, compiled into finite element via the user subroutine, can predict the heterogeneous damage accumulation of the cracking furnace tube made of HP40Nb alloy in a coupled creep-carburisation environment. The predicted total damage is comprised of precipitate coarsening and carburisation as the predominance, while the creep cavitation contributing much less due to the low internal pressure. The distribution of the precipitate coarsening is relatively homogeneous through the thickness, whereas the carburisation causes a steep increased damage value close to the inner surface. With regard to time, the precipitate coarsening damage is predominant in the initial stage, while the total damage is governed by the carburisation process with further exposure. Eventually, the total damage reaches the critical value at 59600 h, with the thickness of carburised layer exceeding 50% of the tube thickness, and the tube fails in the inner surface which agrees with the operational experience. The parametric sensitivity study reveals the importance of determining the Cr-rich carbide area fraction for the life prediction.

Особенности лечения синдрома «сухого глаза» у пациентов с хроническим периферическим увеитом

Introduction. The development of inflammation and violations of the homeostasis of the tear film are of fundamental importance for the occurrence of dry eye disease (DED). In 28–57 % of cases, intermediate uveitis (IU) is accompanied by signs of irritation of the ocular surface and symptoms characteristic of DED. Purpose. Analysis of the effectiveness of complex treatment of DED and IU, including tear replacement and anti-inflammatory therapy in combination with laser retinal coagulation at the extreme periphery of the fundus. Material and methods. The results of treatment of 98 patients were analyzed: the main group – 78 patients – were prescribed complex treatment of DED, the comparison group – 20 patients – only local tear replacement and anti-inflammatory therapy. Evaluation of the effectiveness of the developed method of treatment of combined pathology was carried out after 3 and 6 months. based on the dynamics of OSDI indices, hyperemia of the bulbar conjunctiva, LIPCOF test and Norn test. Results. The use of complex treatment of DED in patients with IU contributes to a statistically significant (p &lt; 0.05) decrease in signs of discomfort according to the results of OSDI to 34.8 %, a decrease in the bulbar conjunctiva hyperemia index to 51.4 %, a decrease in the LIPCOF test index to 22.2 %, an increase in tear film rupture time to 23.3 % with stable CP relief for 6 months observations. Conclusions. Thus, the results obtained clearly demonstrate the effectiveness of the use of complex treatment of DED in patients with IU. The developed method contributes not only to increasing the stability of the tear film, but also to reducing subjective feelings of discomfort and ensuring relief of inflammation at the extreme periphery, which allows us to recommend its wide application. Keywords: dry eye disease, intermediate uveitis, laser coagulation of the extreme periphery of the retina

Abstract 14879: Circadian Variation in Pre-Procedural Rupture of Acute Type A Aortic Dissection

Introduction: Acute type A aortic dissection (ATAAD) is a devasting cardiovascular disease. Though it is recommended by guidelines, urgent open surgery was not accessible for all patients. Transferring patients to comprehensive aortic centers, inadequate medical assistance in low-resource health systems or financial issues would delay the timing of surgery. There have been several reports about the connection between circadian variation and cardiovascular disease. The study was conducted to examine the circadian variation in pre-procedural rupture of ATAAD in the hospital. Methods: The study enrolled ATAAD patients who died from aortic rupture within 7 days since onset in our center from January 2010 to December 2020. Patients who died within 1 hour after admission were excluded. All patients accepted anti-impulse therapy immediately upon admission. Clinical data were retrospectively collected from medical records. Results: In total, 200 ATAAD patients were enrolled in the retrospective observational study. Mean age of recruiters was 55.98 ± 11.82 years and 159 (78.5%) were men. Mean time from onset to admission was 26.78 ± 24.97 hours and mean time from onset to rupture was 48.27 ± 42.01 hours. Distributions of rupture time were visualized through histogram. The peaks of the occurrence of aortic rupture were in 6:00-8:00 (26%) and 18:00-22:00 (36%). Kernel density estimation was consistent with the results. Conclusions: Rupture of ATAAD does not seem to be a random phenomenon, while the peak of occurrence was consistent with the circadian rhythm. Even when the hemodynamic state was well controlled, fluctuant blood pressure and heart rate that influenced by the circadian rhythm would increase the risk of aortic rupture. During 6:00-8:00 and 18:00-22:00, more frequent blood pressure measurement and does adjustment of intravenous anti-impulse drugs might improve aortic rupture reduction. What’s more, bedtime hypertension treatment might also help.

Reflexivity and Relationality in Global Service Learning

This outro is a generative collective conversation between emerging and established scholars in the field of Global Service Learning, at this moment in pandemic time. We met, on zoom, to think expansively about what these pandemic times of rupture have opened up for us in our scholarship and practice. Our orientation was towards reflexivity and relationality. We developed questions to guide our conversation in these two areas, and each of us responded to the questions and to each other. We think together about our own positionalities and ways that we are called to GSL in ways that are explicitly relational. We end by reflection on our own commitments to the field of GSL and why we stay in it knowing the contradictions, the extractive nature of the field, the deep need for decolonization and fraughtness of the space.

A Comparative Study of High Temperature Tensile and Creep Testing Between Standard and Miniature Specimens: Applicability and Limits

This study concerns the quasi-static and time-dependent mechanical behavior obtained via the miniaturized electro-thermal mechanical testing (ETMT) approach for single crystal (SX) and conventional cast Mar-M-247 superalloy. The experimental outcome was benchmarked against standardized testing procedures. It is found that tensile yielding behavior can be captured accurately by the ETMT approach up to 1100 ^{circ }C, provided the appropriate type of thermocouple (T/C) is chosen. Furthermore, creep rupture behavior is underestimated by the miniaturized set-up. High repeatability of the rupture time was obtained for the SX case, whereas a significant scatter was observed for the conventional cast case. The discrepancies are assessed in detail; discussion centers around analytical and practical considerations, such as temperature uncertainty due to parasitic voltage and the choice of T/C, microstructural change as a result of the Joule heating, representative gauge volume, and strain rate non-linearity. Consequently, the applicability and limits of the miniaturized approach are examined critically, and improvements were suggested where appropriate.

Oltipraz, the activator of nuclear factor erythroid 2-related factor 2 (Nrf2), protects against the formation of BAPN-induced aneurysms and dissection of the thoracic aorta in mice by inhibiting activation of the ROS-mediated NLRP3 inflammasome

BackgroundThoracic aortic aneurysm and dissection (TAAD) is caused by the apoptosis and phenotypic transformation of vascular smooth muscle cells (VSMCs). The dysfunction of VSMCs affects their secretion of chemokines such as monocyte chemoattractant protein-1 (MCP-1) to recruit the infiltration of macrophages which release proinflammatory cytokines and matrix metalloproteinases (MMPs) to accelerate the process of TAAD formation. Approach and resultsWe analyzed the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) in aortic tissues of TAAD patients and the β-aminopropionitrile fumarate (BAPN)-induced mouse model, and the levels of Nrf2 were elevated in both aortic lesions. Treatment with the Nrf2 activator oltipraz protects against the formation of BAPN-induced aneurysm and dissection, as demonstrated by a higher survival rate, postponing the time of aortic rupture, and inhibiting aortic luminal dilation. In addition, the thoracic aortas of BAPN-treated mice inhibited the apoptosis and phenotypic transformation of VSMCs. When treated with oltipraz, they had reduced macrophage infiltration proinflammatory cytokines and MMPs. Furthermore, oltipraz treatment promoted the translocation of Nrf2 and downregulated the NLRP3 pathway. ConclusionNrf2 plays a crucial role in protecting against TAAD development, and persistent activation of Nrf2 is a promising therapeutic strategy against the progression of TAAD.

Transwar Art in Japan

This article focuses on the question of periodisations in Japanese art history through a consideration of the long-running careers of four successful but politically and aesthetically diverse artists: Domon Ken (1909­­­­­­­­‒1990), Okamoto Tarō (1911‒1996), Yoshihara Jirō, and Katsura Yuki (1913‒1991). The arc of these artists careers across the prewar, war, and postwar periods upsets popular periodisations in Japan’s art history that assert the postwar as a time of rupture and renewal. My focus is meant to challenge this ‘postwar paradigm’ while elucidating these artist’s negotiation of ethics and plurality during drastically different political eras. How does a reading of their work reveal continuities before and after the war, and what are the political stakes of these continuities?