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1.
Front Public Health ; 12: 1309632, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414898

RESUMO

Background: For high-quality colonoscopies, adequate bowel preparation is a prerequisite, closely associated with the diagnostic accuracy and therapeutic safety of colonoscopy. Although popular-science short videos can help people quickly access health information, the overall quality of such short videos as a source of health information regarding bowel preparation before colonoscopy is unclear. Therefore, we intend to conduct a cross-sectional study to investigate the quality of bowel preparation information before colonoscopy through short videos taken on TikTok and Bilibili. Methods: The Chinese phrases "colonoscopy" and "bowel preparation" were used as keywords to search for and screen the top 100 videos in the comprehensive rankings on TikTok and Bilibili. The Global Quality Score (GQS) and the modified DISCERN score were used to assess the quality of the information provided in these short videos. Results: A total of 186 short videos were included in this study; 56.5% of them were posted by health professionals, whereas 43.5% of them were posted by nonhealth professionals. The overall quality of these videos was unsatisfactory, with a median DISCERN score of 3 (2-4) and a median GQS of 3 (3-4). The radar maps showed that videos posted by gastroenterologists had higher completeness scores regarding outcomes, management, and risk factors, while nongastroenterologists had higher completeness scores concerning adverse effects, symptoms, and definitions of bowel preparation. Additionally, the median DISCERN score and GQS of the videos posted by gastroenterologists were 3 (3-4) and 3 (3-4), respectively, whereas the quality of the videos posted by patients was the worst, with a median DISCERN score of 2 (1-2) and a median GQS of 2 (1.25-3). Conclusion: In conclusion, the overall quality of health information-related videos on bowel preparation before colonoscopy posted on specified short video platforms was not satisfactory. Gastroenterologists provide more information on the outcomes, management, and risk factors for bowel preparation before colonoscopy, while nongastroenterologists focus on adverse effects, symptoms, and definitions of bowel preparation.


Assuntos
Colonoscopia , Educação de Pacientes como Assunto , Humanos , Estudos Transversais , Fatores de Risco , Recursos Audiovisuais
2.
Microbiol Spectr ; 12(1): e0453222, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38095472

RESUMO

IMPORTANCE: As a major pathogen, nervous necrosis virus (NNV) infects more than 120 fish species worldwide and is virulent to larvae and juvenile fish, hampering the development of the fish fry industry. Understanding virus-host interaction and underlying mechanisms is an important but largely unknown issue in fish virus studies. Here, using channel catfish ovary and fathead minnow cells as models for the study of innate immunity signaling, we found that NNV-encoded ProA activated interferon signaling via the retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) pathway which was still suppressed by the infection of wild-type NNV. This finding has important implications for the comprehension of NNV protein function and the immune response from different cells. First, RIG-I is the key node for anti-NNV innate immunity. Second, the response intensity of RLR signaling determines the degree of NNV proliferation. This study expands our knowledge regarding the overview of signal pathways affected by NNV-encoded protein and also highlights potential directions for the control of aquatic viruses.


Assuntos
Bass , Doenças dos Peixes , Animais , Interferons , Bass/metabolismo , Transdução de Sinais , Imunidade Inata , Proteínas Virais/genética
3.
Fish Shellfish Immunol ; 145: 109345, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154761

RESUMO

Type I interferon (IFN) plays a crucial role in the antiviral immune response. Nervous necrosis virus (NNV) and Micropterus salmoides rhabdovirus (MSRV) are the most important viruses in cultured larvae and juveniles, causing great economic losses to fish farming. To better understand the antiviral activities and immunoregulatory role of IFN from orange-spotted grouper (Epinephelus coioides), EcIFNh was cloned from NNV infected sample. EcIFNh has an open reading frame (ORF) of 552 bp and encodes a polypeptide of 183 amino acids. Phylogenetic tree analysis showed that EcIFNh was clustered into the IFNh branch. The tissue distribution analysis revealed that EcIFNh was highly expressed in the liver and brain of healthy orange-spotted grouper. The mRNA levels of EcIFNh were significantly upregulated after poly (I:C) stimulation and NNV or MSRV infection. Furthermore, the promoter of EcIFNh was characterized and significantly activated by EcMDA5, EcMAVS, EcSTING, EcIRF3, and EcIRF7 in the luciferase activity assays. We found that EcIFNh overexpression resisted the replication of NNV and MSRV, while EcIFNh silencing facilitated NNV replication in GB cells. In addition, EcIFNh recombinant protein (rEcIFNh) enhanced the immune response by inducing the expression of ISGs in vivo and in vitro, suggesting the potential application of rEcIFNh for anti-NNV and anti-MSRV. Taken together, our research may offer the foundation for virus-IFN system interaction in orange-spotted grouper.


Assuntos
Bass , Doenças dos Peixes , Nodaviridae , Infecções por Vírus de RNA , Rhabdoviridae , Animais , Filogenia , Proteínas de Peixes/genética , Poli I-C/farmacologia , Necrose , Nodaviridae/fisiologia , Imunidade Inata
4.
Heliyon ; 9(12): e22232, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107273

RESUMO

In this work, the comprehensive properties of flammable casing for underground coal gasification is systematically investigated, including flammable casing material physical, chemical and mechanical properties and full-size flammable casing mechanical properties and burning behavior. The flammable casing material consists of magnesium alloy matrix and rare earth particles, thermal conductivity and expansion property of which are weak. Results of high-temperature tensile test reveal that flammable casing material has good high temperature strength which declines by 30 % at 300 °C. Corrosion rate of flammable casing material is relatively high without extra protection. The full-size flammable casing possesses considerable mechanical property, thread property and high temperature collapse resistance. Burning of flammable casing is safe and stable. Burning rate of flammable casing material can be effectively controlled by water flow. Combustion product of flammable casing presents powder condition, which has no risk of blocking the gasification channel. To sum up, flammable casing is necessary to the realization of underground coal gasifying process, which plays the significant role of the development and application of underground coal gasification technology.

5.
Front Med (Lausanne) ; 10: 1291945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020181

RESUMO

Background: Desmoid-type fibromatosis (DF) is characterized by a rare monoclonal fibroblast proliferation that exhibits variable and unpredictable clinical presentation. DF can be classified into sporadic and hereditary types. Despite extensive research efforts, the exact etiology of DF remains elusive. Case description: A 31-year-old male patient presented to the hospital with a progressively growing mass in the right lower abdomen, accompanied by abdominal discomfort. Symptoms are discovered 1 week before admission. Enteroscopy revealed no evidence of colonic abnormalities, and blood tests did not indicate any abnormalities. Due to the indeterminate nature of the mass during surgery, a partial resection of the ileum and cecum was performed, followed by ileocolonic end-to-end anastomosis, with no postoperative complications. The final pathological diagnosis confirmed primary desmoid-type fibromatosis of the distal ileum (invasive fibromatosis). To effectively manage DF, we recommend a follow-up schedule for patients. This includes appointments every 3 months in the first year following surgery, followed by appointments every 6 months up to the fifth year, and then once a year thereafter. The follow-up examinations should include collection of the patient's medical history, physical examination, blood tests, ultrasounds, CT scans, and other relevant assessments. During the first year of the follow-up period, no further treatment was administered, and the patient remained disease-free. Conclusion: Desmoid-type fibromatosis (DF) originating from the small intestine is an extremely rare condition that exhibits local invasiveness and can be life-threatening. Despite its benign histology, DF has a high local recurrence rate and lacks metastatic potential. Diagnosis of DF remains challenging, especially in cases where surgical intervention is not feasible due to asymptomatic patients or partial organ impairment. In such cases, a "watchful waiting" approach is recommended as the initial treatment strategy. However, when preoperative diagnosis is difficult, surgery is typically considered the best option. Given the potential for local recurrence and the uncertain long-term prognosis, regular follow-up is necessary.

6.
Sci Rep ; 13(1): 20491, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993514

RESUMO

Titanium drill pipe have promising application prospects in ultra-deep drilling, but the nonlinear dynamic characteristics of composite drill strings are very complex. It is very important to use titanium drill pipe safely, economically, and effectively in the drilling process. In this paper, different schemes of the titanium/steel drill pipe composite drill string was designed, and the statics and dynamics characteristics of these composite drill strings were analyzed. The design scheme of titanium/steel composite drill strings were optimized by using whirling characteristics, dynamic stress and vibration acceleration. The results show that the titanium drill pipe can effectively improve the tensile allowance of the wellhead and reduce the whirling velocity, dynamic stress and vibration acceleration of the drill string. By comparing and analyzing the dynamic characteristics of 3 kinds of composite drill strings, the use of titanium drill pipe for the lower 2000 m of the 4'' drill pipe have the smaller dynamic stress and lateral vibration, and less collision with the wellbore. Based on the analysis of vibration and dynamic characteristics, an optimal scheme of drilling operation parameters for the titanium/steel composite drill string was formed finally, which can provide guidance for the use of the drill string composed of titanium/steel drill pipe in natural gas drilling of ultra-deep well.

7.
Chem Commun (Camb) ; 59(88): 13147-13150, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37850533

RESUMO

Herein, a septenary NiCoZnFeCuMnCe hydroxide nanoarray catalyst with a unique wire-on-sheet morphology and high-entropy feature was fabricated, which exhibits boosted pre-oxidation behavior and synergistically enhanced catalytic activity and durability towards the oxygen evolution reaction.

8.
Bioprocess Biosyst Eng ; 46(11): 1591-1611, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37656258

RESUMO

Rape straw was used as the raw material for the biochar in this study, which was then changed using acid, alkali, and magnetic techniques. The laccase was attached using the adsorptions-crosslinking process, and the three modified biochars served as the carriers. The ideal circumstances for laccase immobilization were explored, and both biochar and immobilized laccase's characteristics were examined. The removal of 2,4-dichlorophenol (2,4-DCP) by immobilized laccase from modified biochar and its degradation products were researched. The main conclusions are as follows: the optimal concentration of glutaraldehyde (GLU) was 4%, and the pH was four, and the enzyme dosage was 1.75 mg/mL for the immobilized laccase of acid-modified biochar (SBC@LAC). The optimal concentration of GLU was 5%; the pH was four, and the enzyme dosage was 2 mg/mL for immobilized laccase from alkali-modified biochar (JBC@LAC). The optimal concentration of GLU was 5%; the pH was four, and the enzyme dosage was 1.75 mg/mL for immobilized laccase from magnetically modified biochar (CBC@LAC). SEM images could show the changes in the surface morphology of biochar caused by three modification methods. The BET results demonstrated that acid and magnetic modification increased the specific surface area of biochar, and alkali modification mainly expanded the pore size of biochar. FT-IR and XRD showed that modification and laccase loading had little effect on the structure of biochar. The stability of immobilized laccase was better than that of free laccase in acid-base, heat, and storage. Among the three modified biochar immobilized laccases, JBC@LAC showed the best acid-base stability and thermal stability, and the relative enzyme activity changed the least when pH and temperature conditions changed. The storage stability of SBC@LAC is the best. After 30 days of storage, the relative enzyme activity is still 83%. The removal rates of 2,4-DCP were 57, 99, and 63%, respectively, by SBC@LAC, JBC@LAC, and CBC@LAC. After five reuses, the removal rates of 2,4-DCP by SBC@LAC, JBC@LAC and CBC@LAC were 26, 42, and 27%, respectively. The intermediate products of 2,4-DCP degradation by immobilized laccase were p-phenol, p-benzoquinone and maleic acid.


Assuntos
Enzimas Imobilizadas , Lacase , Lacase/química , Enzimas Imobilizadas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Álcalis
9.
Chem Commun (Camb) ; 59(34): 5098-5101, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37039059

RESUMO

Herein, quinary CoFeNiCuCr sulfide nanosheets with a high-entropy feature and rough surface were fabricated via a topotactic transformation pathway from high-entropy layered metal hydroxides, and display facile pre-oxidation and improved intrinsic activity towards the robust oxygen evolution reaction.

10.
J Colloid Interface Sci ; 642: 41-52, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37001456

RESUMO

Electro-oxidation reactions (EORs) are important half reactions in overall and assisted water electrolysis, which are crucial in achieving economic and sustainable hydrogen production and realizing simultaneous wastewater treatment. Current studies indicate that the high-valence metal ions that are locally enriched in the catalysts or generated in situ during the anodic preoxidation process are active species for EORs. Hence, designing (pre)catalysts with enriched local active sites and boosted preoxidation is of great importance. In this work, with a focus on improving the EOR performance toward the oxygen evolution reaction (OER) and the urea oxidation reaction (UOR), we fabricated a lattice-disordered high-entropy FeCuCoNiZn hydroxide nanoarray catalyst that exhibits robust bifunctional OER and UOR behavior. The high-entropy feature could bring in a unique catalytic ensemble effect and remarkably improve the intrinsic OER/UOR activity. The lattice-disordered structure could not only enrich the local high-valence metal ions as active sites but also provide abundant reactive surface sites to accelerate the preoxidation process, thus leading to enriched active sites for the OER and UOR. Benefitting from the structural merits, the lattice-disordered high-entropy catalyst exhibits excellent OER and UOR activity with low overpotential, large current density and enhanced intrinsic activity, and no performance degradation but dramatic 35.3% and 88.7% enhancement in activity can be achieved during the long-term OER and UOR tests, respectively. The robust OER and UOR performance makes the lattice-disordered high-entropy catalyst a promising candidate for overall and urea-assisted water electrolysis from industrial, agricultural and sanitary wastewater.

11.
J Clin Med ; 12(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36769809

RESUMO

The optimal number of examined lymph nodes (ELNs) for gastric signet ring cell carcinoma recommended by National Comprehensive Cancer Network guidelines remains unclear. This study aimed to determine the optimal number of ELNs and investigate its prognostic significance. In this study, we included 1723 patients diagnosed with gastric signet ring cell carcinoma in the Surveillance, Epidemiology, and End Results database. X-tile software was used to calculate the cutoff value of ELNs, and the optimal number of ELNs was found to be 32 for adequate nodal staging. In addition, we performed propensity score matching (PSM) analysis to compare the 1-, 3-, and 5-year survival rates; 1-, 3-, and 5-year survival rates for total examined lymph nodes (ELNs < 32 vs. ELNs ≥ 32) were 71.7% vs. 80.1% (p = 0.008), 41.8% vs. 51.2% (p = 0.009), and 27% vs. 30.2% (p = 0.032), respectively. Furthermore, a predictive model based on 32 ELNs was developed and displayed as a nomogram. The model showed good predictive ability performance, and machine learning validated the importance of the optimal number of ELNs in predicting prognosis.

12.
J Colloid Interface Sci ; 630(Pt A): 257-265, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242885

RESUMO

Enriching the active sites and enhancing the intrinsic activity of a single site are two basic strategies for improving the activity toward the electrocatalytic oxygen evolution reaction (OER), and designing an advanced microstructure with a boosted pre-oxidation process can further guarantee durability toward long-term catalysis. Herein, we propose a dual oxidation strategy of a Co Prussian blue analog (Co PBA), which simultaneously achieves Co3+ active site enrichment, in situ CeO2 decoration and lattice disordering with abundant undercoordinated sites, realizing highly efficient and ultrastable OER performance. The dual oxidation process can induce the enrichment of high-valence Co ions by combined chemical oxidation and d-f electron coupling compared to the singly oxidized catalysts, thereby providing more active sites with enhanced intrinsic activity for the early triggered OER process. In addition, the disordered lattice can provide abundant reactive Co sites for the pre-oxidation process, thereby leading to obvious activation of the catalysts and remarkable operational stability due to the substantially accumulated Co3+ sites. Benefitting from the structural advantages of lattice-disordered dual-oxidized Co PBA nanocages, a low overpotential of 240 mV can be achieved for a 10 mA cm-2 current density, and the large catalytic current density and intrinsic activity are among the best compared to those of previously reported PBA-based and PBA-derived catalysts and even RuO2 and IrO2. In addition, ultrastable OER behavior with a 263 % activity enhancement in 150 h can result, making the dual-oxidized catalyst a promising candidate for water electrolysis.

13.
Front Oncol ; 13: 1309724, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38375202

RESUMO

Purpose: Several surgical risk models are widely utilized in general surgery to predict postoperative morbidity. However, no studies have been undertaken to examine the predictive efficacy of these models in biliary tract cancer patients, and other perioperative variables can also influence morbidity. As a result, the study's goal was to examine these models alone, as well as risk models combined with disease-specific factors, in predicting severe complications. Methods: A retrospective study of 129 patients was carried out. Data on demographics, surgery, and outcomes were gathered. These model equations were used to determine the morbidity risks. Severe morbidity was defined as the complication comprehensive index ≥ 40. Results: Severe morbidity was observed in 25% (32/129) patients. Multivariate analysis demonstrated that four parameters [comprehensive risk score ≥1, T stage, albumin decrease value, and international normalized ratio (INR)] had a significant influence on the probability of major complications. The area under the curve (AUC) of combining the four parameters was assessed as having strong predictive value and was superior to the Estimation of Physiologic Ability and Surgical Stress System (E-PASS) alone (the AUC value was 0.858 vs. 0.724, p = 0.0375). The AUC for the modified E-PASS (mE-PASS) and Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM) in patients over the age of 70 was classified as no predictive value (p = 0.217 and p = 0.063, respectively). Conclusion: The mE-PASS and POSSUM models are ineffective in predicting postoperative morbidity in patients above the age of 70. In biliary tract cancer (BTC) patients undergoing radical operation, a combination of E-PASS and perioperative parameters generates a reasonable prediction value for severe complications.

14.
Chem Commun (Camb) ; 58(85): 11981-11984, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36214391

RESUMO

Herein, a high-entropy amorphous oxycyanide porous nanocube pre-catalyst was developed for the oxygen evolution reaction (OER). Benefitting from the facile pre-oxidation and enhanced intrinsic activity of the high-entropy catalyst, a highly efficient and ultrastable OER performance was achieved.

15.
Sci Rep ; 12(1): 16586, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36198740

RESUMO

In order to investigate the influence of minor Ru on the electrochemical behaviour and structural characteristics of passive films on the surface of Ti-6Al-4V alloys under various oil and gas exploration conditions, electrochemical techniques, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and corrosion simulation tests were carried out. The results revealed that the oil and gas exploration conditions had a serious impact on the electrochemical behaviour and corrosion resistance of the tested alloys. The passivation film resistance and corrosion potential of the tested titanium alloys were significantly reduced with increasing acidity and temperature. With the addition of minor ruthenium, the potential of the passive film on the Ti-6Al-4V-0.11Ru alloy surface increased because of the high surface potential of the ruthenium element. The contents of metallic ruthenium and tetravalent titanium oxide TiO2 in the surface film of the Ti-6Al-4V-0.11Ru alloy both increased with increasing temperature, which led to increase the thickness, stability, corrosion resistance and repairability of the passive film on the surface of the Ti-6Al-4V-0.11Ru alloy being better than those qualities of Ti-6Al-4V. These results were also confirmed by corrosion simulation tests.

16.
J Colloid Interface Sci ; 627: 891-899, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35901568

RESUMO

Oxygen evolution reaction (OER), the rate-limiting half reaction of water electrolysis, plays as a crucial role in improving the overall efficiency of the coupled hydrogen evolution. To date, earth-abundant OER catalysts have been extensively studied, while unfortunately their catalytic activity and operational stability still need to be further optimized. In this work, we fabricated a highly efficient OER catalyst based on two-dimensional (2D) NiCoFe layered double hydroxide (LDH)/MoO3 stacked heterostructure with enriched active sites and optimal electronic structure via an electrostatic-driven self-assembly process. The rough surface of the 2D heterostructure could offer abundant reactive sites for the pre-oxidation reaction, thereby leading to fast generation of the high-valence active species for OER, and the multi-metal synergy and oriented interlayered charge transfer could further enhance the intrinsic OER activity, finally resulting in enhanced OER performance with low overpotential, large current density, high intrinsic activity and excellent operational stability.


Assuntos
Oxigênio , Água , Catálise , Hidrogênio , Eletricidade Estática
17.
Exp Ther Med ; 24(2): 537, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35837064

RESUMO

The present study aimed to explore the biological functions of microRNA (miR)-146b-5p and homeodomain interacting protein kinase 1 (HIPK1) in the progression of hepatic fibrosis (HF) and to identify the underlying mechanism. A rat HF model was established by administering a subcutaneous injection of carbon tetrachloride (CCl4). Relative levels of miR-146b-5p and HIPK1 in fibrotic rat liver tissues and the rat hepatic stellate cell (HSC) line HSC-T6 were measured by quantitative reverse transcription PCR, western blotting and immunohistochemistry. Following activation of HSC-T6 cells by lipopolysaccharide (LPS) induction, cell viability was examined by MTT assay. Transfection of miR-146b-5p mimic or inhibitor into HSC-T6 cells was performed, with the aim to identify the influence of miR-146b-5p on HSC-T6 cell behavior. The targeting relationship between miR-146b-5p and HIPK1 was predicted by TargetScan 7.2 and StarBase 3.0 and it was later verified by a dual-luciferase reporter assay. Through lentivirus transfection, the biological function of HIPK1 in regulating the progression of HF and the underlying mechanism were investigated. The results showed that miR-146b-5p was upregulated in liver tissues of rats with HF and activated HSC-T6 cells, while HIPK1 was downregulated in liver tissues of rats with HF and activated HSC-T6 cells. miR-146b-5p was able to upregulate the activation markers of LPS-induced HSC-T6 cells, upregulate COL1A1 and TGF-ß, increase cell viability and contribute to fibrosis progression. HIPK1 was validated as the direct target of miR-146b-5p and its overexpression could effectively reduce the effect of miR-146b-5p in contribution to the progression of HF. In conclusion, miR-146b-5p was significantly upregulated during the progression of HF. By targeting and downregulating HIPK1, miR-146b-5p could significantly activate HSCs, upregulate COL1A1 and TGF-ß and contribute to fibrosis progression. miR-146b-5p is a potential biomarker and therapeutic target for HF.

18.
Chem Commun (Camb) ; 58(43): 6360-6363, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35543095

RESUMO

In this work, Co-based nanocatalysts with variable degrees of sulfurization (DoS) were fabricated for the oxygen evolution reaction (OER). The partially sulfurized catalyst with a medium DoS could exhibit a promoted pre-oxidation process, leading to a highly efficient and ultrastable OER performance.

19.
Chem Commun (Camb) ; 58(48): 6845-6848, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35616607

RESUMO

In this work, cerium-incorporated Co-based catalysts encapsulated in nitrogen-doped carbon were fabricated for the electrocatalytic hydrazine oxidation reaction (HzOR). The Ce incorporation could lead to the formation of surface oxide nanolayers with a disordered lattice, endowing the catalyst with enriched active sites and enhanced intrinsic activity for promoted HzOR.

20.
Sci Rep ; 12(1): 4526, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296762

RESUMO

Titanium alloy has become a promising candidate material for oil country tubular goods (OCTGs) in harsh service environments owing to its high specific strength, low density, low elastic modulus, excellent toughness, excellent anti-fatigue and corrosion resistance. However, because the high-quality natural gas resources in China are mainly concentrated deep underground, titanium alloy tubing and casing will bear great external pressure loads underground, so the collapse strength of titanium alloy tubing and casing is very important for the safety of the string in the well. In this paper, a new collapse strength calculation model, the strength collapse criterion model (SCM), was proposed for titanium alloy tubing and casing. 35 different specifications of titanium alloy tubing and casing were selected for the full-scale collapse tests to verify the reliability of the established SCM model. Furthermore, the effect of different key parameters (such as strength, ovality, eccentricity and residual stress) on collapse strength of titanium alloy pipes were investigated systematically and compared with the same specifications of steel pipes. The strength collapse criterion model and analysis results can provide a technical reference for the design and use of titanium alloy OCTGs in the petroleum and natural gas industries.

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