This study aims to provide the basic knowledge for furnace refractory design by investigating refractory property changes occurred in a hydrogen atmosphere.Since refractory bricks are thermodynamically stable in a hyd...This study aims to provide the basic knowledge for furnace refractory design by investigating refractory property changes occurred in a hydrogen atmosphere.Since refractory bricks are thermodynamically stable in a hydrogen atmosphere at 1100°C,we tried to find out the minute changes.In this experiment,a refractory brick was prepared by andalusite,mullite chamotte,and clay as raw materials and heated to 1100°C in a 100%hydrogen atmosphere for 72 h.It was found that the strength of the brick was decreased and the color was changed to black by the reduction of impurities.And in addition,this study covered research on the slaking risk of MgO raw materials because the minimum temperature is expected to 400°C in fluidized reduction furnaces unlike shaft furnaces.展开更多
BACKGROUND Many patients with ulcerative colitis(UC)do not respond well to,or tolerate conventional and biological therapies.There is currently no consensus on the treatment of refractory UC.Studies have demonstrated ...BACKGROUND Many patients with ulcerative colitis(UC)do not respond well to,or tolerate conventional and biological therapies.There is currently no consensus on the treatment of refractory UC.Studies have demonstrated that the selective Janus kinase 1 inhibitor upadacitinib,a small-molecule drug,is effective and safe for treating UC.However,no studies have revealed that upadacitinib is effective in treating refractory UC with primary nonresponse to infliximab and vedolizumab.CASE SUMMARY We report the case of a 44-year-old male patient with a chief complaint of bloody diarrhoea with mucus and pus,in addition to dizziness.The patient had recurrent disease after receiving mesalazine,prednisone,azathioprine,infliximab and vedolizumab over four years.Based on the endoscopic findings and pathological biopsy,the patient was diagnosed with refractory UC.In particular,the patient showed primary nonresponse to infliximab and vedolizumab.Based on the patient’s history and recurrent disease,we decided to administer upadacitinib.During hospitalisation,the patient was received upadacitinib under our guidance.Eight weeks after the initiation of upadacitinib treatment,the patient’s symptoms and endoscopic findings improved significantly.No notable adverse reactions have been reported to date.CONCLUSION Our case report suggests that upadacitinib may represent a valuable strategy for treating refractory UC with primary nonresponse.展开更多
W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a po...W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a powder metallurgy process combining mechanical alloying and spark plasma sintering (SPS). The SPSed samples contained two phases, in which the matrix is RHEA with a body-centered cubic structure, while the oxide phase was most likely Ta2VO6through a combined analysis of X-ray diffraction (XRD),energy-dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The higher oxygen affinity of Ta and V may explain the preferential formation of their oxide phases based on thermodynamic calculations. Electron backscatter diffraction (EBSD) revealed an average grain size of 6.2μm. WTaVCr RHEA showed a peak compressive strength of 2997 MPa at room temperature and much higher micro-and nano-hardness than W and other W-based RHEAs in the literature. Their high Rockwell hardness can be retained to at least 1000°C.展开更多
AIM:To evaluate the efficacy and safety of the intravitreal dexamethasone implant in naive and refractory patients with diabetic macular edema(DME).METHODS:PubMed,Embase,Web of Science,and Medline databases were searc...AIM:To evaluate the efficacy and safety of the intravitreal dexamethasone implant in naive and refractory patients with diabetic macular edema(DME).METHODS:PubMed,Embase,Web of Science,and Medline databases were searched.The main outcomes were best-corrected visual acuity(BCVA)and central retinal thickness(CRT).The secondary outcomes included mean number of injections,intraoperative or postoperative complications including intraocular pressure(IOP)elevation and cataract.RESULTS:Ten comparative studies involving a total of 1000 DME eyes including 402 naive eyes and 598 refractory eyes were selected.The postoperative BCVA in the naive group was significantly better than in the refractory group[mean difference(MD)-0.11,95% confidence interval(CI)-0.17 to-0.05,P=0.0003;MD 8.69,95%CI 5.08 to 12.30,P<0.00001].Additionally,the naive group got greater improvement of BCVA change as well as more gains of BCVA letters than the refractory group[MD 7.71,95%CI 2.02 to 13.40,P=0.008;odds ratio(OR)2.99,95%CI 2.05 to 4.37,P<0.00001].The subgroup analysis revealed that the naive group had significantly higher BCVA gains of≥5,≥10,and≥15 letters compared to the refractory group(P=0.002,0.0001,0.003,respectively).No significant difference was detected between the two groups in either postoperative CRT(MD-22.36,95%CI-46.39 to 1.66,P=0.07)or the overall mean number of injections(MD-0.08,95%CI-0.38 to 0.22,P=0.61).Intraoperative and postoperative complications including the elevation of IOP(OR 0.47,95%CI 0.20 to 1.13,P=0.09)and cataract(OR 1.78,95%CI 0.97 to 3.24,P=0.06)showed no significant differences between the two groups during the follow-up time.CONCLUSION:Intravitreal dexamethasone implants for DME can improve anatomical and functional outcomes in both naive and refractory eyes and have a well-acceptable safety profile.Moreover,naive eyes maintain better visual outcomes than refractory eyes.It provides further evidence of better visual response when used for naive eyes as firstline therapy.展开更多
AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated en...AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC groups.Both groups showed significant IOP reduction after glaucoma surgery.The GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group.CONCLUSION:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK.GDI is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.展开更多
In this editorial we comment on an article published in World Journal of Clinical Cases in 2024,in which a case of refractory ulcerative colitis(UC)was discussed based on the response to different lines of biologics.D...In this editorial we comment on an article published in World Journal of Clinical Cases in 2024,in which a case of refractory ulcerative colitis(UC)was discussed based on the response to different lines of biologics.Different studies showed that different classes of biologics have their advantages and disadvantages in the treatment of refractory UC.Certain classes are superior to others and if tried earlier on would lead to a possible change in the outcome.展开更多
BACKGROUND Gastrinoma is characterized by an excessive release of gastrin,leading to hypersecretion of gastric acid,subsequently resulting in recurrent peptic ulcers,chronic diarrhea,and even esophageal strictures.Thi...BACKGROUND Gastrinoma is characterized by an excessive release of gastrin,leading to hypersecretion of gastric acid,subsequently resulting in recurrent peptic ulcers,chronic diarrhea,and even esophageal strictures.This case report aims to improve awareness and facilitate early diagnosis and treatment of gastrinoma by presenting a rare case of gastrinoma with refractory benign esophageal stricture(RBES).Additionally,it highlights the persistent challenges that gastroenterologists encounter in managing RBES.CASE SUMMARY This case demonstrates a patient with gastrinoma who developed RBES and complete esophageal obstruction despite management with maximal acid suppressive therapy,multiple endoscopic bougie dilations and endoscopic incisional therapy(EIT).CONCLUSION It is essential to diagnose gastrinoma as early as possible,as inadequately controlled acid secretion over an extended period increases the risk of developing severe esophageal strictures.In patients with esophageal strictures causing complete luminal obstruction,blind reopening EIT presents challenges and carries a high risk of perforation.展开更多
BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymph...BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and intussusception.Here,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult.CASE SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months prior.Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding.Conservative management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after surgery.Ultimately,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active bleeding.After singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical resection.No complications or recurrences were observed postoperatively.CONCLUSION Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding.Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis.Surgical resection is an effective management method.展开更多
BACKGROUND Due to the lack of published literature about treatment of refractory hepatopulmonary syndrome(HPS)after liver transplant(LT),this case adds information and experience on this issue along with a treatment w...BACKGROUND Due to the lack of published literature about treatment of refractory hepatopulmonary syndrome(HPS)after liver transplant(LT),this case adds information and experience on this issue along with a treatment with positive outcomes.HPS is a complication of end-stage liver disease,with a 10%-30%incidence in cirrhotic patients.LT can reverse the physiopathology of this process and restore normal oxygenation.However,in some cases,refractory hypoxemia persists,and extracorporeal membrane oxygenation(ECMO)can be used as a rescue therapy with good results.CASE SUMMARY A 59-year-old patient with alcohol-related liver cirrhosis and portal hypertension was included in the LT waiting list for HPS.He had good liver function(Model for End-Stage Liver Disease score 12,Child-Pugh class B7).He had pulmonary fibrosis and a mild restrictive respiratory pattern with a basal oxygen saturation of 82%.The macroaggregated albumin test result was>30.Spirometry demonstrated a forced expiratory volume in one second(FEV1)of 78%,forced vital capacity(FVC)of 74%,FEV1/FVC ratio of 81%,diffusion capacity for carbon monoxide of 42%,and carbon monoxide transfer coefficient of 57%.He required domiciliary oxygen at 2 L/min(16 h/d).The patient was admitted to the intensive care unit(ICU)and extubated in the first 24 h,needing high-flow therapy and non-invasive ventilation and inhaled nitric oxide afterwards.Reintubation was needed after 72 h.Due to the non-response to supportive therapies,installation of ECMO was decided with progressive recovery after 9 d.Extubation was possible on the tenth day,maintaining a high-flow nasal cannula and de-escalating to conventional oxygen therapy after 48 h.He was discharged from ICU on postoperative day(POD)20 with a 90%-92%oxygen saturation.Steroid recycling was needed twice for acute rejection.The patient was discharged from hospital on POD 27 with no symptoms,with an 89%-90%oxygen saturation.CONCLUSION Due to the favorable results observed,ECMO could become the central axis of treatment of HPS and refractory hypoxemia after LT.展开更多
Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some...Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some circumstances resistance to erosion from abrasive particles.Given the large processing output of the heavy industries such as the cement and steel ones which both require high temperature processes,the refractories structures span various meters and weight of several tons.As the water removal stage of hydraulic bonded castables in industrial sites takes hours(10-60 h)due to the risk of explosive spalling,efforts to mitigate it are commonly studied.This has provided theoretical understanding of the general aspects of drying and important tools,such as the thermogravimetry analysis(TGA),for the design of refractory compositions with higher explosive spalling resistance.However,the optimization of this process is still far from the industrial reality especially because the actual linings that require the drying are orders of magnitude larger than the samples considered in the laboratory tests.Therefore,this study proposed the analysis of the sample volume effect on the water removal dynamics through TGA of high alumina castables with calcium aluminate cement.Conventionalφ5 cm×5 cm cylindrical samples were assessed in a laboratory scale equipment whereas macro TGA were carried out considering 20 cm×20 cm×20 cm and 30 cm×30 cm×30 cm cubic samples.Additionally,the effect of polymeric fibers was also considered.It was found out that the different thermal gradients within the macro TGA samples resulted in an inflection on the sample’s heating rate and that the mass loss was affected by the volume considered,especially for the composition without additives.These findings highlight the requirement of carefully taking into consideration the different dimensional sizes and thermal gradients in the samples when analyzing and interpreting the laboratory studies,and especially when trying to extrapolate such results to the industrial reality.展开更多
Some refractory linings that protect metallic vessels from the hot temperature of the products they contain are made of masonries with or without mortar.The joints play an important role,reducing the stresses in the m...Some refractory linings that protect metallic vessels from the hot temperature of the products they contain are made of masonries with or without mortar.The joints play an important role,reducing the stresses in the masonries during heating.Furthermore,the presence of these joints makes the behaviour of the masonry nonlinear and orthotropic.To perform a thermomechanical simulation using a finite element method of an industrial vessel that contains hundreds or thousands of bricks and joints,microscopic models are not suitable due to the high computational time and the management of the behaviour of the joints(opening/closing)which affects the convergence.To overcome these problems,it is proposed to replace the masonry by a homogeneous material that has a behaviour equivalent to the set of bricks and joints,using a periodic homogenization technique.Since the joints can be closed or open,the equivalent material will have a different behaviour according to the joint state.Furthermore,refractory materials have an elastic-viscoplastic behaviour at high temperatures.So,the equivalent material will have an orthotropic elastic-viscoplastic behaviour,requiring a nonlinear homogenisation technique.An overview of this approach developed at University of Orléans is presented with two industrial applications(blast-furnace and steel ladle).展开更多
Refractory materials,as the crucial foundational materials in high-temperature industrial processes such as metallurgy and construction,are inevitably subjected to corrosion and penetration from high-temperature media...Refractory materials,as the crucial foundational materials in high-temperature industrial processes such as metallurgy and construction,are inevitably subjected to corrosion and penetration from high-temperature media during their service.Traditionally,observing the in-situ degradation process of refractory materials in complex high-temperature environments has presented challenges.Post-corrosion analysis are commonly employed to assess the slag resistance of refractory materials and understand the corrosion mechanisms.However,these methods often lack information on the process under the conditions of thermal-chemical-mechanical coupling,leading to potential biases in the analysis results.In this work,we developed a non-contact high-temperature machine vision technology by the integrating Digital Image Correlation(DIC)with a high-temperature visualization system to explore the corrosion behavior of Al2O3-SiO2 refractories against molten glass and Al2O3-MgO dry ramming refractories against molten slag at different temperatures.This technology enables realtime monitoring of the 2D or 3D overall strain and average strain curves of the refractory materials and provides continuous feedback on the progressive corrosion of the materials under the coupling conditions of thermal,chemical,and mechanical factors.Therefore,it is an innovative approach for evaluating the service behavior and performance of refractory materials,and is expected to promote the digitization and intelligence of the refractory industry,contributing to the optimization and upgrading of product performance.展开更多
Objective:To analyze the value of D-dimer(D-D),interleukin-6(IL-6),and IL-18 in the differential diagnosis of children with refractory Mycoplasma pneumoniae pneumonia(RMPP).Methods:The medical records of 92 children w...Objective:To analyze the value of D-dimer(D-D),interleukin-6(IL-6),and IL-18 in the differential diagnosis of children with refractory Mycoplasma pneumoniae pneumonia(RMPP).Methods:The medical records of 92 children with Mycoplasma pneumoniae pneumonia(MPP)treated in the hospital were selected for retrospective analysis from January 2023 to January 2024.After comprehensive examinations such as computed tomography examination of the chest,48 children with general Mycoplasma pneumoniae pneumonia(GMPP)were put in the GMPP group and 44 children with RMPP were grouped in the RMPP group.The IL-6,IL-18,and D-D levels were compared between the two groups,and the receiver operating characteristic(ROC)curves were plotted to analyze their value for differential diagnosis of RMPP.Results:The levels of IL-6,IL-18,and D-D in the RMPP group were higher than those in the GMPP group(P<0.05);the ROC curves showed that the specificity of the differential diagnosis of IL-6,IL-18,and D-D was higher,and their diagnostic value was significant.Conclusion:Determination of IL-6,IL-18,and D-D levels in children with MPP can further diagnose the children’s condition,which can help physicians formulate targeted treatment plans,and is of great significance to the improvement of the children’s condition,which is worthy of attention.展开更多
Background: Gastroparesis is one of the complications of diabetes mellitus, and long-term gastroparesis seriously affects patients quality of life. Most of the patients can be relieved after lifestyle improvement and ...Background: Gastroparesis is one of the complications of diabetes mellitus, and long-term gastroparesis seriously affects patients quality of life. Most of the patients can be relieved after lifestyle improvement and medication, but refractory gastroparesis is difficult to relieve, and is still a challenge in clinical treatment. Aim: To report a case of a patient with diabetic nephropathy combined with refractory gastroparesis, and to analyse the mechanism, diagnosis, severity grading, treatment of refractory gastroparesis in conjunction with a review of the literature, and to investigate the causes of recurrent nausea and vomiting in diabetic nephropathy patients with refractory diabetic gastroparesis and the possible effective treatment options. Case Presentation: The patient was hospitalised for recurrent nausea and vomiting and diagnosed with diabetic nephropathy and gastroparesis. Symptoms recurred after medication and peritoneal dialysis, and the patients symptoms were relieved after multifaceted interventions. Conclusion: Diabetic nephropathy and refractory gastroparesis can both manifest as digestive tract symptoms, and in the face of this complex disease, it is necessary to analyse the various etiological factors and take comprehensive treatment measures.展开更多
In Burkina Faso, one of the three largest gold producers in West Africa, foundry activity is often paralyzed when basic equipment such as crucibles and cups are not available or should be imported. However, previous s...In Burkina Faso, one of the three largest gold producers in West Africa, foundry activity is often paralyzed when basic equipment such as crucibles and cups are not available or should be imported. However, previous studies have shown the availability of kaolinite-rich clay resources that could be used for the local manufacture of silico-aluminous ceramic crucibles. This work allowed to manufacture industrial ceramic crucibles with local clays and then they were tested in foundry industry. The materials were manufactured from three (03) raw materials including two clays (SAB and ROU) and sand. The chemical and mineral analysis has shown that the raw materials are suitable for the formulation of refractory materials. The results of characterization of the materials formulated showed that the properties of use are appreciable. The porosity of the materials is relatively low (23 - 28 vol%) with a diametral compressive strength between 0.61 and 1.34 MPa. Crucibles sintered at 1250˚C with a stay of 2 hours have a mechanical strength capable of supporting the weight of the ores contained. These crucibles have a refractoriness under load (T0.5) above 1141˚C and resist chemical attacks. Tests were carried out in the industry at 1100˚C, and the results were satisfactory.展开更多
A 63-year-old man with diabetes and asymptomatic coronary artery disease developed refractory ventricular arrhythmia at 20 hours at rest after his second COVID-19 vaccine. Despite significant stenosis in the coronary ...A 63-year-old man with diabetes and asymptomatic coronary artery disease developed refractory ventricular arrhythmia at 20 hours at rest after his second COVID-19 vaccine. Despite significant stenosis in the coronary arteries, there was no evidence of acute or old myocardial infarction, heart failure, myocarditis or structural abnormalities on post-mortem to account for the substrate for the fatal arrhythmia. The refractory and incessant nature of the ventricular fibrillation and post-mortem finding of a grossly elevated unexplained IgE level (in the absence of acute myocardial infarction) suggested the possibility of Kounis Syndrome or allergic acute coronary syndrome.展开更多
BACKGROUND Due to increasing resistance rates of Helicobacter pylori(H.pylori)to different antibiotics,failures in eradication therapies are becoming more frequent.Even though eradication criteria and treatment algori...BACKGROUND Due to increasing resistance rates of Helicobacter pylori(H.pylori)to different antibiotics,failures in eradication therapies are becoming more frequent.Even though eradication criteria and treatment algorithms for first-line and second-line therapy against H.pylori infection are well-established,there is no clear recommendation for third-line and rescue therapy in refractory H.pylori infection.AIM To perform a systematic review evaluating the efficacy and safety of rescue therapies against refractory H.pylori infection.METHODS A systematic search of available rescue treatments for refractory H.pylori infection was conducted on the National Library of Medicine’s PubMed search platform based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Randomized or non-randomized clinical trials and observational studies evaluating the effectiveness of H.pylori infection rescue therapies were included.RESULTS Twenty-eight studies were included in the analysis of mean eradication rates as rescue therapy,and 21 of these were selected for analysis of mean eradication rate as third-line treatment.For rifabutin-,sitafloxacin-,levofloxacin-,or metronidazole-based triple-therapy as third-line treatment,mean eradication rates of 81.6%and 84.4%,79.4%and 81.5%,55.7%and 60.6%,and 62.0%and 63.0%were found in intention-to-treat(ITT)and per-protocol(PP)analysis,respectively.For third-line quadruple therapy,mean eradication rates of 69.2%and 72.1%were found for bismuth quadruple therapy(BQT),88.9%and 90.9%for bismuth quadruple therapy,three-in-one,Pylera®(BQT-Pylera),and 61.3%and 64.2%for non-BQT)in ITT and PP analysis,respectively.For rifabutin-,sitafloxacin-,levofloxacin-,or metronidazole-based triple therapy as rescue therapy,mean eradication rates of 75.4%and 78.8%,79.4 and 81.5%,55.7%and 60.6%,and 62.0%and 63.0%were found in ITT and PP analysis,respectively.For quadruple therapy as rescue treatment,mean eradication rates of 76.7%and 79.2%for BQT,84.9%and 87.8%for BQT-Pylera,and 61.3%and 64.2%for non-BQT were found in ITT and PP analysis,respectively.For susceptibility-guided therapy,mean eradication rates as third-line and rescue treatment were 75.0%in ITT and 79.2%in PP analysis.CONCLUSION We recommend sitafloxacin-based triple therapy containing vonoprazan in regions with low macrolide resistance profile.In regions with known resistance to macrolides or unavailability of bismuth,rifabutin-based triple therapy is recommended.展开更多
Refractory high-entropy alloys(RHEAs)have promising applications as the new generation of hightemperature alloys in hypersonic vehicles,aero-engines,gas turbines,and nuclear power plants.This study focuses on the micr...Refractory high-entropy alloys(RHEAs)have promising applications as the new generation of hightemperature alloys in hypersonic vehicles,aero-engines,gas turbines,and nuclear power plants.This study focuses on the microstructures and mechanical properties of the NbMoTaW(HfN)_(x)(x=0,0.3,0.7,and 1.0)RHEAs.The alloys consist of multiple phases of body-centered cubic(BCC),hafnium nitride(HfN),or multicomponent nitride(MN)phases.As the x contents increase,the grain size becomes smaller,and the strength gradually increases.The compressive yield strengths of the NbMoTaWHfN RHEA at ambient temperature,1000,1400,and 1800℃ were found to be 1682,1192,792,and 288 MPa,respectively.The high-temperature strength of this alloy is an inspiring result that exceeds the high temperature and strength of most known alloys,including high-entropy alloys,refractory metals,and superalloys.The HfN phase has a significant effect on strengthening due to its high structural stability and sluggish grain coarsening,even at ultra-high temperatures.Its superior properties endow the NbMoTaWHfN RHEA with potential for a wide range of engineering applications at ultra-high temperatures.This work offers a strategy for the design of high-temperature alloys and proposes an ultra-high-temperature alloy with potential for future engineering applications.展开更多
BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment failure...BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment failure.TiPN is rarely predictable and recognized,especially in CD.It is necessary to develop a risk model to predict TiPN occurrence.AIM To develop and compare a predictive model of TiPN using machine learning based on comprehensive clinical and genetic variables.METHODS A retrospective cohort of 164 CD patients from January 2016 to June 2022 was used to establish the model.The National Cancer Institute Common Toxicity Criteria Sensory Scale(version 4.0)was used to assess TiPN.With 18 clinical features and 150 genetic variables,five predictive models were established and evaluated by the confusion matrix receiver operating characteristic curve(AUROC),area under the precision-recall curve(AUPRC),specificity,sensitivity(recall rate),precision,accuracy,and F1 score.RESULTS The top-ranking five risk variables associated with TiPN were interleukin-12 rs1353248[P=0.0004,odds ratio(OR):8.983,95%confidence interval(CI):2.497-30.90],dose(mg/d,P=0.002),brainderived neurotrophic factor(BDNF)rs2030324(P=0.001,OR:3.164,95%CI:1.561-6.434),BDNF rs6265(P=0.001,OR:3.150,95%CI:1.546-6.073)and BDNF rs11030104(P=0.001,OR:3.091,95%CI:1.525-5.960).In the training set,gradient boosting decision tree(GBDT),extremely random trees(ET),random forest,logistic regression and extreme gradient boosting(XGBoost)obtained AUROC values>0.90 and AUPRC>0.87.Among these models,XGBoost and GBDT obtained the first two highest AUROC(0.90 and 1),AUPRC(0.98 and 1),accuracy(0.96 and 0.98),precision(0.90 and 0.95),F1 score(0.95 and 0.98),specificity(0.94 and 0.97),and sensitivity(1).In the validation set,XGBoost algorithm exhibited the best predictive performance with the highest specificity(0.857),accuracy(0.818),AUPRC(0.86)and AUROC(0.89).ET and GBDT obtained the highest sensitivity(1)and F1 score(0.8).Overall,compared with other state-of-the-art classifiers such as ET,GBDT and RF,XGBoost algorithm not only showed a more stable performance,but also yielded higher ROC-AUC and PRC-AUC scores,demonstrating its high accuracy in prediction of TiPN occurrence.CONCLUSION The powerful XGBoost algorithm accurately predicts TiPN using 18 clinical features and 14 genetic variables.With the ability to identify high-risk patients using single nucleotide polymorphisms,it offers a feasible option for improving thalidomide efficacy in CD patients.展开更多
BACKGROUND The lymphatic system is crucial in maintaining the body fluid homeostasis.A dysfunctional lymphatic system may contribute to the refractoriness of ascites and edema in cirrhosis patients.Therefore,assessmen...BACKGROUND The lymphatic system is crucial in maintaining the body fluid homeostasis.A dysfunctional lymphatic system may contribute to the refractoriness of ascites and edema in cirrhosis patients.Therefore,assessment of lymphatic dysfunction in cirrhosis patients with refractory ascites(RA)can be crucial as it would call for using different strategies for fluid mobilization.AIM To assessing the magnitude,spectrum,and clinical associations of lymphatic dysfunction in liver cirrhosis patients with RA.METHODS This observational study included 155 consecutive cirrhosis patients with RA.The presence of clinical signs of lymphedema,such as peau d’orange appearance and positive Stemmer sign,intestinal lymphangiectasia(IL)on duodenal biopsy seen as dilated vessels in the lamina propria with strong D2-40 immunohistochemistry,and chylous ascites were used to diagnose the overt lymphatic dysfunctions.RESULTS A total of 69(44.5%)patients out of 155 had evidence of lymphatic dysfunction.Peripheral lymphedema,found in 52(33.5%)patients,was the most common manifestation,followed by IL in 42(27.0%)patients,and chylous ascites in 2(1.9%)patients.Compared to patients without lymphedema,those with lymphedema had higher mean age,median model for end-stage liver disease scores,mean body mass index,mean ascitic fluid triglyceride levels,and proportion of patients with hypoproteinemia(serum total protein<5 g/dL)and lymphocytopenia(<15%of total leukocyte count).Patients with IL also had a higher prevalence of lymphocytopenia and hypoproteinemia(28.6%vs.9.1%,P=0.004).Seven(13%)patients with lymphedema had lower limb cellulitis compared to none in those without it.On multivariate regression analysis,factors independently associated with lymphatic dysfunction included obesity[odds ratio(OR):4.2,95%confidence intervals(95%CI):1.1–15.2,P=0.027],lymphocytopenia[OR:6.2,95%CI:2.9–13.2,P<0.001],and hypoproteinemia[OR:3.7,95%CI:1.5–8.82,P=0.003].CONCLUSION Lymphatic dysfunction is common in cirrhosis patients with RA.Significant indicators of its presence include hypoproteinemia and lymphocytopenia,which are likely due to the loss of lymphatic fluid from the circulation.Future efforts to mobilize fluid in these patients should focus on methods to improve lymphatic drainage.展开更多
基金supported by the Korea Planning & Evaluation Institute of Industrial Technology (KEIT)the Ministry of Trade, Industry & Energy (MOTIE, Korea) of the Republic of Korea (No. RS2023-00262421)
文摘This study aims to provide the basic knowledge for furnace refractory design by investigating refractory property changes occurred in a hydrogen atmosphere.Since refractory bricks are thermodynamically stable in a hydrogen atmosphere at 1100°C,we tried to find out the minute changes.In this experiment,a refractory brick was prepared by andalusite,mullite chamotte,and clay as raw materials and heated to 1100°C in a 100%hydrogen atmosphere for 72 h.It was found that the strength of the brick was decreased and the color was changed to black by the reduction of impurities.And in addition,this study covered research on the slaking risk of MgO raw materials because the minimum temperature is expected to 400°C in fluidized reduction furnaces unlike shaft furnaces.
基金Supported by Shenzhen Science and Technology Program,No.JCYJ20220530154013031Guangdong Province Health and Health Appropriate Technology Promotion Project,No.2023385Guangdong Province Grassroots Science Popularization Action Plan,No.20240205.
文摘BACKGROUND Many patients with ulcerative colitis(UC)do not respond well to,or tolerate conventional and biological therapies.There is currently no consensus on the treatment of refractory UC.Studies have demonstrated that the selective Janus kinase 1 inhibitor upadacitinib,a small-molecule drug,is effective and safe for treating UC.However,no studies have revealed that upadacitinib is effective in treating refractory UC with primary nonresponse to infliximab and vedolizumab.CASE SUMMARY We report the case of a 44-year-old male patient with a chief complaint of bloody diarrhoea with mucus and pus,in addition to dizziness.The patient had recurrent disease after receiving mesalazine,prednisone,azathioprine,infliximab and vedolizumab over four years.Based on the endoscopic findings and pathological biopsy,the patient was diagnosed with refractory UC.In particular,the patient showed primary nonresponse to infliximab and vedolizumab.Based on the patient’s history and recurrent disease,we decided to administer upadacitinib.During hospitalisation,the patient was received upadacitinib under our guidance.Eight weeks after the initiation of upadacitinib treatment,the patient’s symptoms and endoscopic findings improved significantly.No notable adverse reactions have been reported to date.CONCLUSION Our case report suggests that upadacitinib may represent a valuable strategy for treating refractory UC with primary nonresponse.
基金supported by the National Science Foundation under Grant No.CMMI-1762190The research was performed in part in the Nebraska Nanoscale Facility:National Nanotechnology Coordinated Infrastructure and the Nebraska Center for Materials and Nanoscience (and/or NERCF),which are supported by the National Science Foundation under Award ECCS:2025298+1 种基金the Nebraska Research Initiativesupported by the U.S.Department of Energy,Office of Nuclear Energy under DOE Idaho Operations Office Contract DE-AC07-051D14517 as part of a Nuclear Science User Facilities experiment。
文摘W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a powder metallurgy process combining mechanical alloying and spark plasma sintering (SPS). The SPSed samples contained two phases, in which the matrix is RHEA with a body-centered cubic structure, while the oxide phase was most likely Ta2VO6through a combined analysis of X-ray diffraction (XRD),energy-dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The higher oxygen affinity of Ta and V may explain the preferential formation of their oxide phases based on thermodynamic calculations. Electron backscatter diffraction (EBSD) revealed an average grain size of 6.2μm. WTaVCr RHEA showed a peak compressive strength of 2997 MPa at room temperature and much higher micro-and nano-hardness than W and other W-based RHEAs in the literature. Their high Rockwell hardness can be retained to at least 1000°C.
基金Supported by Zhongda Hospital Affiliated to Southeast University,Jiangsu Province High-Level Hospital Construction Funds(No.CZXM-GSP-KY).
文摘AIM:To evaluate the efficacy and safety of the intravitreal dexamethasone implant in naive and refractory patients with diabetic macular edema(DME).METHODS:PubMed,Embase,Web of Science,and Medline databases were searched.The main outcomes were best-corrected visual acuity(BCVA)and central retinal thickness(CRT).The secondary outcomes included mean number of injections,intraoperative or postoperative complications including intraocular pressure(IOP)elevation and cataract.RESULTS:Ten comparative studies involving a total of 1000 DME eyes including 402 naive eyes and 598 refractory eyes were selected.The postoperative BCVA in the naive group was significantly better than in the refractory group[mean difference(MD)-0.11,95% confidence interval(CI)-0.17 to-0.05,P=0.0003;MD 8.69,95%CI 5.08 to 12.30,P<0.00001].Additionally,the naive group got greater improvement of BCVA change as well as more gains of BCVA letters than the refractory group[MD 7.71,95%CI 2.02 to 13.40,P=0.008;odds ratio(OR)2.99,95%CI 2.05 to 4.37,P<0.00001].The subgroup analysis revealed that the naive group had significantly higher BCVA gains of≥5,≥10,and≥15 letters compared to the refractory group(P=0.002,0.0001,0.003,respectively).No significant difference was detected between the two groups in either postoperative CRT(MD-22.36,95%CI-46.39 to 1.66,P=0.07)or the overall mean number of injections(MD-0.08,95%CI-0.38 to 0.22,P=0.61).Intraoperative and postoperative complications including the elevation of IOP(OR 0.47,95%CI 0.20 to 1.13,P=0.09)and cataract(OR 1.78,95%CI 0.97 to 3.24,P=0.06)showed no significant differences between the two groups during the follow-up time.CONCLUSION:Intravitreal dexamethasone implants for DME can improve anatomical and functional outcomes in both naive and refractory eyes and have a well-acceptable safety profile.Moreover,naive eyes maintain better visual outcomes than refractory eyes.It provides further evidence of better visual response when used for naive eyes as firstline therapy.
文摘AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC groups.Both groups showed significant IOP reduction after glaucoma surgery.The GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI group.CONCLUSION:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after DSAEK.GDI is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.
文摘In this editorial we comment on an article published in World Journal of Clinical Cases in 2024,in which a case of refractory ulcerative colitis(UC)was discussed based on the response to different lines of biologics.Different studies showed that different classes of biologics have their advantages and disadvantages in the treatment of refractory UC.Certain classes are superior to others and if tried earlier on would lead to a possible change in the outcome.
文摘BACKGROUND Gastrinoma is characterized by an excessive release of gastrin,leading to hypersecretion of gastric acid,subsequently resulting in recurrent peptic ulcers,chronic diarrhea,and even esophageal strictures.This case report aims to improve awareness and facilitate early diagnosis and treatment of gastrinoma by presenting a rare case of gastrinoma with refractory benign esophageal stricture(RBES).Additionally,it highlights the persistent challenges that gastroenterologists encounter in managing RBES.CASE SUMMARY This case demonstrates a patient with gastrinoma who developed RBES and complete esophageal obstruction despite management with maximal acid suppressive therapy,multiple endoscopic bougie dilations and endoscopic incisional therapy(EIT).CONCLUSION It is essential to diagnose gastrinoma as early as possible,as inadequately controlled acid secretion over an extended period increases the risk of developing severe esophageal strictures.In patients with esophageal strictures causing complete luminal obstruction,blind reopening EIT presents challenges and carries a high risk of perforation.
文摘BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and intussusception.Here,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult.CASE SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months prior.Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding.Conservative management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after surgery.Ultimately,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active bleeding.After singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical resection.No complications or recurrences were observed postoperatively.CONCLUSION Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding.Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis.Surgical resection is an effective management method.
文摘BACKGROUND Due to the lack of published literature about treatment of refractory hepatopulmonary syndrome(HPS)after liver transplant(LT),this case adds information and experience on this issue along with a treatment with positive outcomes.HPS is a complication of end-stage liver disease,with a 10%-30%incidence in cirrhotic patients.LT can reverse the physiopathology of this process and restore normal oxygenation.However,in some cases,refractory hypoxemia persists,and extracorporeal membrane oxygenation(ECMO)can be used as a rescue therapy with good results.CASE SUMMARY A 59-year-old patient with alcohol-related liver cirrhosis and portal hypertension was included in the LT waiting list for HPS.He had good liver function(Model for End-Stage Liver Disease score 12,Child-Pugh class B7).He had pulmonary fibrosis and a mild restrictive respiratory pattern with a basal oxygen saturation of 82%.The macroaggregated albumin test result was>30.Spirometry demonstrated a forced expiratory volume in one second(FEV1)of 78%,forced vital capacity(FVC)of 74%,FEV1/FVC ratio of 81%,diffusion capacity for carbon monoxide of 42%,and carbon monoxide transfer coefficient of 57%.He required domiciliary oxygen at 2 L/min(16 h/d).The patient was admitted to the intensive care unit(ICU)and extubated in the first 24 h,needing high-flow therapy and non-invasive ventilation and inhaled nitric oxide afterwards.Reintubation was needed after 72 h.Due to the non-response to supportive therapies,installation of ECMO was decided with progressive recovery after 9 d.Extubation was possible on the tenth day,maintaining a high-flow nasal cannula and de-escalating to conventional oxygen therapy after 48 h.He was discharged from ICU on postoperative day(POD)20 with a 90%-92%oxygen saturation.Steroid recycling was needed twice for acute rejection.The patient was discharged from hospital on POD 27 with no symptoms,with an 89%-90%oxygen saturation.CONCLUSION Due to the favorable results observed,ECMO could become the central axis of treatment of HPS and refractory hypoxemia after LT.
基金the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)-Finance Code 001.The authors would like to thank the Fundacao de Amparo a Pesquisa do Estado de Sao Paulo-FAPESP(grant number:2021/00251-0).Finally,the authors are also greatly thankful for FIRE support to carry out this work.
文摘Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some circumstances resistance to erosion from abrasive particles.Given the large processing output of the heavy industries such as the cement and steel ones which both require high temperature processes,the refractories structures span various meters and weight of several tons.As the water removal stage of hydraulic bonded castables in industrial sites takes hours(10-60 h)due to the risk of explosive spalling,efforts to mitigate it are commonly studied.This has provided theoretical understanding of the general aspects of drying and important tools,such as the thermogravimetry analysis(TGA),for the design of refractory compositions with higher explosive spalling resistance.However,the optimization of this process is still far from the industrial reality especially because the actual linings that require the drying are orders of magnitude larger than the samples considered in the laboratory tests.Therefore,this study proposed the analysis of the sample volume effect on the water removal dynamics through TGA of high alumina castables with calcium aluminate cement.Conventionalφ5 cm×5 cm cylindrical samples were assessed in a laboratory scale equipment whereas macro TGA were carried out considering 20 cm×20 cm×20 cm and 30 cm×30 cm×30 cm cubic samples.Additionally,the effect of polymeric fibers was also considered.It was found out that the different thermal gradients within the macro TGA samples resulted in an inflection on the sample’s heating rate and that the mass loss was affected by the volume considered,especially for the composition without additives.These findings highlight the requirement of carefully taking into consideration the different dimensional sizes and thermal gradients in the samples when analyzing and interpreting the laboratory studies,and especially when trying to extrapolate such results to the industrial reality.
基金the PhD students(M.Ali,J.Brulin,M.Landreau,T.M.H Nguyen)who have participated to this study,the different compagnies(CPM,RHI-Magnesita,Saint-Gobain,and Tata Steel),the European Commission(ATHOR project,764987 Grant)the Federation for International Refractory Research and Education which have funded it.
文摘Some refractory linings that protect metallic vessels from the hot temperature of the products they contain are made of masonries with or without mortar.The joints play an important role,reducing the stresses in the masonries during heating.Furthermore,the presence of these joints makes the behaviour of the masonry nonlinear and orthotropic.To perform a thermomechanical simulation using a finite element method of an industrial vessel that contains hundreds or thousands of bricks and joints,microscopic models are not suitable due to the high computational time and the management of the behaviour of the joints(opening/closing)which affects the convergence.To overcome these problems,it is proposed to replace the masonry by a homogeneous material that has a behaviour equivalent to the set of bricks and joints,using a periodic homogenization technique.Since the joints can be closed or open,the equivalent material will have a different behaviour according to the joint state.Furthermore,refractory materials have an elastic-viscoplastic behaviour at high temperatures.So,the equivalent material will have an orthotropic elastic-viscoplastic behaviour,requiring a nonlinear homogenisation technique.An overview of this approach developed at University of Orléans is presented with two industrial applications(blast-furnace and steel ladle).
基金supported by the National Natural Science Foundation of China(52272022)Key Program of Natural Science Foundation of Hubei Province(2021CFA071).
文摘Refractory materials,as the crucial foundational materials in high-temperature industrial processes such as metallurgy and construction,are inevitably subjected to corrosion and penetration from high-temperature media during their service.Traditionally,observing the in-situ degradation process of refractory materials in complex high-temperature environments has presented challenges.Post-corrosion analysis are commonly employed to assess the slag resistance of refractory materials and understand the corrosion mechanisms.However,these methods often lack information on the process under the conditions of thermal-chemical-mechanical coupling,leading to potential biases in the analysis results.In this work,we developed a non-contact high-temperature machine vision technology by the integrating Digital Image Correlation(DIC)with a high-temperature visualization system to explore the corrosion behavior of Al2O3-SiO2 refractories against molten glass and Al2O3-MgO dry ramming refractories against molten slag at different temperatures.This technology enables realtime monitoring of the 2D or 3D overall strain and average strain curves of the refractory materials and provides continuous feedback on the progressive corrosion of the materials under the coupling conditions of thermal,chemical,and mechanical factors.Therefore,it is an innovative approach for evaluating the service behavior and performance of refractory materials,and is expected to promote the digitization and intelligence of the refractory industry,contributing to the optimization and upgrading of product performance.
文摘Objective:To analyze the value of D-dimer(D-D),interleukin-6(IL-6),and IL-18 in the differential diagnosis of children with refractory Mycoplasma pneumoniae pneumonia(RMPP).Methods:The medical records of 92 children with Mycoplasma pneumoniae pneumonia(MPP)treated in the hospital were selected for retrospective analysis from January 2023 to January 2024.After comprehensive examinations such as computed tomography examination of the chest,48 children with general Mycoplasma pneumoniae pneumonia(GMPP)were put in the GMPP group and 44 children with RMPP were grouped in the RMPP group.The IL-6,IL-18,and D-D levels were compared between the two groups,and the receiver operating characteristic(ROC)curves were plotted to analyze their value for differential diagnosis of RMPP.Results:The levels of IL-6,IL-18,and D-D in the RMPP group were higher than those in the GMPP group(P<0.05);the ROC curves showed that the specificity of the differential diagnosis of IL-6,IL-18,and D-D was higher,and their diagnostic value was significant.Conclusion:Determination of IL-6,IL-18,and D-D levels in children with MPP can further diagnose the children’s condition,which can help physicians formulate targeted treatment plans,and is of great significance to the improvement of the children’s condition,which is worthy of attention.
文摘Background: Gastroparesis is one of the complications of diabetes mellitus, and long-term gastroparesis seriously affects patients quality of life. Most of the patients can be relieved after lifestyle improvement and medication, but refractory gastroparesis is difficult to relieve, and is still a challenge in clinical treatment. Aim: To report a case of a patient with diabetic nephropathy combined with refractory gastroparesis, and to analyse the mechanism, diagnosis, severity grading, treatment of refractory gastroparesis in conjunction with a review of the literature, and to investigate the causes of recurrent nausea and vomiting in diabetic nephropathy patients with refractory diabetic gastroparesis and the possible effective treatment options. Case Presentation: The patient was hospitalised for recurrent nausea and vomiting and diagnosed with diabetic nephropathy and gastroparesis. Symptoms recurred after medication and peritoneal dialysis, and the patients symptoms were relieved after multifaceted interventions. Conclusion: Diabetic nephropathy and refractory gastroparesis can both manifest as digestive tract symptoms, and in the face of this complex disease, it is necessary to analyse the various etiological factors and take comprehensive treatment measures.
文摘In Burkina Faso, one of the three largest gold producers in West Africa, foundry activity is often paralyzed when basic equipment such as crucibles and cups are not available or should be imported. However, previous studies have shown the availability of kaolinite-rich clay resources that could be used for the local manufacture of silico-aluminous ceramic crucibles. This work allowed to manufacture industrial ceramic crucibles with local clays and then they were tested in foundry industry. The materials were manufactured from three (03) raw materials including two clays (SAB and ROU) and sand. The chemical and mineral analysis has shown that the raw materials are suitable for the formulation of refractory materials. The results of characterization of the materials formulated showed that the properties of use are appreciable. The porosity of the materials is relatively low (23 - 28 vol%) with a diametral compressive strength between 0.61 and 1.34 MPa. Crucibles sintered at 1250˚C with a stay of 2 hours have a mechanical strength capable of supporting the weight of the ores contained. These crucibles have a refractoriness under load (T0.5) above 1141˚C and resist chemical attacks. Tests were carried out in the industry at 1100˚C, and the results were satisfactory.
文摘A 63-year-old man with diabetes and asymptomatic coronary artery disease developed refractory ventricular arrhythmia at 20 hours at rest after his second COVID-19 vaccine. Despite significant stenosis in the coronary arteries, there was no evidence of acute or old myocardial infarction, heart failure, myocarditis or structural abnormalities on post-mortem to account for the substrate for the fatal arrhythmia. The refractory and incessant nature of the ventricular fibrillation and post-mortem finding of a grossly elevated unexplained IgE level (in the absence of acute myocardial infarction) suggested the possibility of Kounis Syndrome or allergic acute coronary syndrome.
文摘BACKGROUND Due to increasing resistance rates of Helicobacter pylori(H.pylori)to different antibiotics,failures in eradication therapies are becoming more frequent.Even though eradication criteria and treatment algorithms for first-line and second-line therapy against H.pylori infection are well-established,there is no clear recommendation for third-line and rescue therapy in refractory H.pylori infection.AIM To perform a systematic review evaluating the efficacy and safety of rescue therapies against refractory H.pylori infection.METHODS A systematic search of available rescue treatments for refractory H.pylori infection was conducted on the National Library of Medicine’s PubMed search platform based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Randomized or non-randomized clinical trials and observational studies evaluating the effectiveness of H.pylori infection rescue therapies were included.RESULTS Twenty-eight studies were included in the analysis of mean eradication rates as rescue therapy,and 21 of these were selected for analysis of mean eradication rate as third-line treatment.For rifabutin-,sitafloxacin-,levofloxacin-,or metronidazole-based triple-therapy as third-line treatment,mean eradication rates of 81.6%and 84.4%,79.4%and 81.5%,55.7%and 60.6%,and 62.0%and 63.0%were found in intention-to-treat(ITT)and per-protocol(PP)analysis,respectively.For third-line quadruple therapy,mean eradication rates of 69.2%and 72.1%were found for bismuth quadruple therapy(BQT),88.9%and 90.9%for bismuth quadruple therapy,three-in-one,Pylera®(BQT-Pylera),and 61.3%and 64.2%for non-BQT)in ITT and PP analysis,respectively.For rifabutin-,sitafloxacin-,levofloxacin-,or metronidazole-based triple therapy as rescue therapy,mean eradication rates of 75.4%and 78.8%,79.4 and 81.5%,55.7%and 60.6%,and 62.0%and 63.0%were found in ITT and PP analysis,respectively.For quadruple therapy as rescue treatment,mean eradication rates of 76.7%and 79.2%for BQT,84.9%and 87.8%for BQT-Pylera,and 61.3%and 64.2%for non-BQT were found in ITT and PP analysis,respectively.For susceptibility-guided therapy,mean eradication rates as third-line and rescue treatment were 75.0%in ITT and 79.2%in PP analysis.CONCLUSION We recommend sitafloxacin-based triple therapy containing vonoprazan in regions with low macrolide resistance profile.In regions with known resistance to macrolides or unavailability of bismuth,rifabutin-based triple therapy is recommended.
基金supported by the National Key Research and Development Program of China(2023YFE0201600 and 2018YFC1902400)the National Natural Science Foundation of China(51975582)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Refractory high-entropy alloys(RHEAs)have promising applications as the new generation of hightemperature alloys in hypersonic vehicles,aero-engines,gas turbines,and nuclear power plants.This study focuses on the microstructures and mechanical properties of the NbMoTaW(HfN)_(x)(x=0,0.3,0.7,and 1.0)RHEAs.The alloys consist of multiple phases of body-centered cubic(BCC),hafnium nitride(HfN),or multicomponent nitride(MN)phases.As the x contents increase,the grain size becomes smaller,and the strength gradually increases.The compressive yield strengths of the NbMoTaWHfN RHEA at ambient temperature,1000,1400,and 1800℃ were found to be 1682,1192,792,and 288 MPa,respectively.The high-temperature strength of this alloy is an inspiring result that exceeds the high temperature and strength of most known alloys,including high-entropy alloys,refractory metals,and superalloys.The HfN phase has a significant effect on strengthening due to its high structural stability and sluggish grain coarsening,even at ultra-high temperatures.Its superior properties endow the NbMoTaWHfN RHEA with potential for a wide range of engineering applications at ultra-high temperatures.This work offers a strategy for the design of high-temperature alloys and proposes an ultra-high-temperature alloy with potential for future engineering applications.
基金National Natural Science Foundation of China,No.81973398,No.81730103,No.81573507 and No.82020108031The National Key Research and Development Program,No.2017YFC0909300 and No.2016YFC0905001+5 种基金Guangdong Provincial Key Laboratory of Construction Foundation,No.2017B030314030 and No.2020B1212060034Science and Technology Program of Guangzhou,No.201607020031National Engineering and Technology Research Center for New Drug Druggability Evaluation(Seed Program of Guangdong Province),No.2017B090903004The 111 Project,No.B16047China Postdoctoral Science Foundation,No.2019M66324,No.2020M683140 and No.2020M683139Natural Science Foundation of Guangdong Province,No.2022A1515012549 and No.2023A1515012667.
文摘BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment failure.TiPN is rarely predictable and recognized,especially in CD.It is necessary to develop a risk model to predict TiPN occurrence.AIM To develop and compare a predictive model of TiPN using machine learning based on comprehensive clinical and genetic variables.METHODS A retrospective cohort of 164 CD patients from January 2016 to June 2022 was used to establish the model.The National Cancer Institute Common Toxicity Criteria Sensory Scale(version 4.0)was used to assess TiPN.With 18 clinical features and 150 genetic variables,five predictive models were established and evaluated by the confusion matrix receiver operating characteristic curve(AUROC),area under the precision-recall curve(AUPRC),specificity,sensitivity(recall rate),precision,accuracy,and F1 score.RESULTS The top-ranking five risk variables associated with TiPN were interleukin-12 rs1353248[P=0.0004,odds ratio(OR):8.983,95%confidence interval(CI):2.497-30.90],dose(mg/d,P=0.002),brainderived neurotrophic factor(BDNF)rs2030324(P=0.001,OR:3.164,95%CI:1.561-6.434),BDNF rs6265(P=0.001,OR:3.150,95%CI:1.546-6.073)and BDNF rs11030104(P=0.001,OR:3.091,95%CI:1.525-5.960).In the training set,gradient boosting decision tree(GBDT),extremely random trees(ET),random forest,logistic regression and extreme gradient boosting(XGBoost)obtained AUROC values>0.90 and AUPRC>0.87.Among these models,XGBoost and GBDT obtained the first two highest AUROC(0.90 and 1),AUPRC(0.98 and 1),accuracy(0.96 and 0.98),precision(0.90 and 0.95),F1 score(0.95 and 0.98),specificity(0.94 and 0.97),and sensitivity(1).In the validation set,XGBoost algorithm exhibited the best predictive performance with the highest specificity(0.857),accuracy(0.818),AUPRC(0.86)and AUROC(0.89).ET and GBDT obtained the highest sensitivity(1)and F1 score(0.8).Overall,compared with other state-of-the-art classifiers such as ET,GBDT and RF,XGBoost algorithm not only showed a more stable performance,but also yielded higher ROC-AUC and PRC-AUC scores,demonstrating its high accuracy in prediction of TiPN occurrence.CONCLUSION The powerful XGBoost algorithm accurately predicts TiPN using 18 clinical features and 14 genetic variables.With the ability to identify high-risk patients using single nucleotide polymorphisms,it offers a feasible option for improving thalidomide efficacy in CD patients.
文摘BACKGROUND The lymphatic system is crucial in maintaining the body fluid homeostasis.A dysfunctional lymphatic system may contribute to the refractoriness of ascites and edema in cirrhosis patients.Therefore,assessment of lymphatic dysfunction in cirrhosis patients with refractory ascites(RA)can be crucial as it would call for using different strategies for fluid mobilization.AIM To assessing the magnitude,spectrum,and clinical associations of lymphatic dysfunction in liver cirrhosis patients with RA.METHODS This observational study included 155 consecutive cirrhosis patients with RA.The presence of clinical signs of lymphedema,such as peau d’orange appearance and positive Stemmer sign,intestinal lymphangiectasia(IL)on duodenal biopsy seen as dilated vessels in the lamina propria with strong D2-40 immunohistochemistry,and chylous ascites were used to diagnose the overt lymphatic dysfunctions.RESULTS A total of 69(44.5%)patients out of 155 had evidence of lymphatic dysfunction.Peripheral lymphedema,found in 52(33.5%)patients,was the most common manifestation,followed by IL in 42(27.0%)patients,and chylous ascites in 2(1.9%)patients.Compared to patients without lymphedema,those with lymphedema had higher mean age,median model for end-stage liver disease scores,mean body mass index,mean ascitic fluid triglyceride levels,and proportion of patients with hypoproteinemia(serum total protein<5 g/dL)and lymphocytopenia(<15%of total leukocyte count).Patients with IL also had a higher prevalence of lymphocytopenia and hypoproteinemia(28.6%vs.9.1%,P=0.004).Seven(13%)patients with lymphedema had lower limb cellulitis compared to none in those without it.On multivariate regression analysis,factors independently associated with lymphatic dysfunction included obesity[odds ratio(OR):4.2,95%confidence intervals(95%CI):1.1–15.2,P=0.027],lymphocytopenia[OR:6.2,95%CI:2.9–13.2,P<0.001],and hypoproteinemia[OR:3.7,95%CI:1.5–8.82,P=0.003].CONCLUSION Lymphatic dysfunction is common in cirrhosis patients with RA.Significant indicators of its presence include hypoproteinemia and lymphocytopenia,which are likely due to the loss of lymphatic fluid from the circulation.Future efforts to mobilize fluid in these patients should focus on methods to improve lymphatic drainage.