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Zhang, Lei, Weimin Long, Dong Du, Zhibin Fan, Chao Jiang e Xia Jin. "A Novel Diamond/AlSi Composite Coating on Ti-6Al-4V SubStrate Made by Ultrasonic-Assisted Brazing". Coatings 13, n.º 9 (13 de setembro de 2023): 1596. http://dx.doi.org/10.3390/coatings13091596.
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Ultrasonic-assisted brazing (UAB) technology has been introduced to prepare the diamond/AlSi composite coating on Ti-6Al-4V substrate. The microstructure and wear properties of the coating were studied. The results showed that AlSi filler metal had a certain spreading and climbing phenomenon on the diamond surface, indicating a significant improvement in wettability between AlSi filler metal and diamond by ultrasonic-assisted brazing. Under ultrasound action, the microstructure of AlSi brazing alloy was greatly refined, and the Ti atoms in the Ti-6Al-4V substrate diffused to the interface between diamond and AlSi brazing alloy and formed TiC on diamond particles. There was no thermal damage to diamond particles when the brazing temperature was 750 °C. UAB improved the microhardness of the coating alloy matrix due to the increasing quantity and distribution range of TiAl3 as reinforced particles but had no obvious effect on the microhardness of the Ti-6Al-4V substrate. The wear resistance of Ti-6Al-4V substrate with diamond/AlSi composite coating was promoted due to the dense diamond particles, the formed TiC on diamond particles, and the increase in microhardness of the alloy matrix of diamond/AlSi coating under ultrasound action.
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Gao, Jie, Lingfan Zhang, Xin Liu e Wenqing Zhang. "Hierarchically structured, well-dispersed Ti4+ cross-linked chitosan as an efficient and recyclable sponge-like adsorbent for anionic azo-dye removal". RSC Advances 6, n.º 108 (2016): 106260–67. http://dx.doi.org/10.1039/c6ra24446g.
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One novel of sponge-like Ti4+ cross-linked chitosan (SL-TiCs) was prepared. The SL-TiCs had multiply nano-layer twisted sheets and high content of Ti4+, which can provide plenty channels for mass transfer and active sites for dyes adsorption.
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Kunheen, Khayas Omer, MC Tomichan, Rajeev PB e Adarsh Krishna K. Bhat. "Novel Adaptation of Suture Bridge Technique for Greater Tuberosity Redisplacement Post ORIF With PHILOS- A Technical Note". Trauma International 6, n.º 2 (2020): 15–18. http://dx.doi.org/10.13107/ti.2020.v06i02.107.
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Isolated Greater tuberosity (GT) fractures still pose a therapeutic challenge due to the wide variety of treatment options and lack of proper comparative studies on outcome. Plating still remains a valid option but has several unfavorable effects. One among them is redisplacement of tuberosity postoperatively especially in cases with comminution which may easily be missed in regular plain radiographs. Conventional techniques of fixation may remain insufficient in such scenarios. We hereby propose an adaptation of a described technique, in a 45-year-old male presenting with redisplacement of GT post plate fixation. Open double-row suture bridge construct was used to fix the displaced fragment maintaining the plate insitu and the patient had an excellent functional and radiological outcome on follow-up. Keywords: Greater tuberosity fracture; Comminution; Double-row fixation; Suture anchor; Suture Bridge technique; PHILOS; Redisplacement.
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Yang, Jitao. "A novel Method for Sternal Fixation in Cardiac Surgery: Initial Experience". Angiology & Vascular Surgery 7, n.º 2 (22 de julho de 2022): 1–5. http://dx.doi.org/10.24966/avs-7397/100096.
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Objectives: To investigate whether the Ni-Ti-shaped memory alloy embracing plate is an effective treatment for post -sternotomy complications and to see if it can improve the mechanical stability of sternal closure and to evaluate its initial outcome. Methods: One-hundred twenty patients from January 2012 through December 2015 underwent sternal fixation with the Ni-Ti-shaped memory alloy embracing plate in cardiac sugery. Sternal healing was evaluated by physical examination, wound healing complications and the Computed Tomography (CT) showings of coaptation the sternal halves. The pain scores were recorded preoperatively and postoperatively on day 3 to 7, discharge, 4 weeks, and 3 and 6 months. Results: The patients with Ni-Ti-shaped memory alloy embracing plate fixation had less postoprative comlications, such as fat liquefication, mediastinitis, sternal dehiscenc. The postoperative pain scores were significantly lower in patients with sternal fixation of embracing plates than that with wire cerclage. The life quanlity was imporoved in embracing plate fixation patients. Conclusion: The Ni-Ti-shaped memory alloy embracing plate significantly improved the sternal stability closure and life quanlity and reduced postoperative pain in cardiac surgery.
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Zhang, Ningbo, Boyu Ju, Taiqing Deng, Sen Fu, Cungao Duan, Yiwei Song, Yijun Jiang et al. "Effect of Volume Fraction of Reinforcement on Microstructure and Mechanical Properties of In Situ (Ti, Nb)B/Ti2AlNb Composites with Tailored Three-Dimensional Network Architecture". Materials 15, n.º 24 (19 de dezembro de 2022): 9070. http://dx.doi.org/10.3390/ma15249070.
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The mechanical properties of (Ti, Nb)B/Ti2AlNb composites were expected to improve further by utilizing spark plasma sintering (SPS) and inducing the novel three-dimensional network architecture. In this study, (Ti, Nb)B/Ti2AlNb composites with the novel architecture were successfully fabricated by ball milling the LaB6 and Ti2AlNb mixed powders and subsequent SPS consolidation. The influence of the (Ti, Nb)B content on the microstructure and mechanical properties of the composites was revealed by using the scanning electron microscope (SEM), transmission electron microscopy (TEM) and electronic universal testing machine. The microstructural characterization demonstrated that the boride crystallized into a B27 structure and the α2-precipitated amount increased with the (Ti, Nb)B increasing. When the (Ti, Nb)B content reached 4.9 vol%, both the α2 and reinforcement exhibited a continuous distribution along the prior particle boundaries (PPBs). The tensile test displayed that the tensile strength of the composites presented an increasing trend with the increasing (Ti, Nb)B content followed by a decreasing trend. The composite with a 3.2 vol% reinforcement had the optimal mechanical properties; the yield strengths of the composite at 25 and 650 °C were 998.3 and 774.9 MPa, showing an 11.8% and 9.2% improvement when compared with the Ti2AlNb-based alloy. Overall, (Ti, Nb)B possessed an excellent strengthening effect and inhibited the strength weakening of the PPBs area at high temperatures; the reinforcement content mainly affected the mechanical properties of the (Ti, Nb)B/Ti2AlNb composites by altering the α2-precipitated amount and the morphology of (Ti, Nb)B in the PPBs area. Both the continuous precipitation of the brittle α2 phase and the agglomeration of the (Ti, Nb)B reinforcement dramatically deteriorated the mechanical properties.
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Chen, Tijun, Libo Geng, He Qin e Min Gao. "Core-Shell-Structured Particle Reinforced A356 Matrix Composite Prepared by Powder-Thixoforming: Effect of Reheating Temperature". Materials 11, n.º 9 (13 de setembro de 2018): 1718. http://dx.doi.org/10.3390/ma11091718.
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A novel core-shell-structured Ti-(Al-Si-Ti) particle (Ti-(Al-Si-Ti)p) reinforced A356 matrix composite was fabricated by a new method, powder thixoforming, which combines the merits of both powder metallurgy and semisolid thixoforming. The effects of reheating temperature on the microstructure and tensile properties of the resulting composite were investigated. The results indicated that the thickening of the Al-Si-Ti compound shells, with rising the reheating temperature, significantly enhanced the strengthening role, but the fracture and peeling of the shells, at higher than 600 °C, impaired the strengthening effect. The composite formed at 600 °C had a favorable tensile elongation of 8.3% besides high tensile strengths. During tensile testing, the Ti@(Al-Si-Ti)p frequently fractured across the Ti cores and occasionally cracked around the Ti cores, but preferentially fractured between the outer cracked shells and the inner cores for the composites thixoformed at higher than 600 °C. The delayed formation of cracks in the Ti-(Al-Si-Ti)p and the small size of the cracks contributed to ductility improvement. The MSL model, modified according to the Ti@(Al-Si-Ti)p characteristics, was essentially suitable for predicting the yield strength of such composites. The largest contribution to the strength was resulted from solid solution strengthening of Ti element, but the strengthening role from geometrically necessary dislocations was significantly improved as the reheating temperature rose from 590 °C to 600 °C.
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Li, Zhi, Guangbo Che, Wei Jiang, Lihui Liu e Hairui Wang. "Visible-light-driven CQDs@MIL-125(Ti) nanocomposite photocatalyst with enhanced photocatalytic activity for the degradation of tetracycline". RSC Advances 9, n.º 57 (2019): 33238–45. http://dx.doi.org/10.1039/c9ra05600a.
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A novel CQDs@MIL-125(Ti) photocatalyst had been synthesized by a facile solvothermal process for the degradation of TC. The possible degradation mechanism was proposed based on the active species trapping experiments.
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Ewid, Mohammed, Mervat Naguib, Ali Alamer, Hala El Saka, Sharifa Alduraibi, Abdullah AlGoblan e Elzaki Ahmed. "Updated ACR Thyroid Imaging Reporting and Data Systems in risk stratification of thyroid nodules: 1-year experience at a Tertiary Care Hospital in Al-Qassim". Egyptian Journal of Internal Medicine 31, n.º 4 (dezembro de 2019): 868–73. http://dx.doi.org/10.4103/ejim.ejim_143_19.
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Abstract Background Thyroid imaging reporting and data system (TI-RADS) is assessment of risk stratification of thyroid nodules, using a score. A novel ACR (American College of Radiology) TI-RADS has been recently suggested by American College of Radiology. But, the utility of ACR TI-RADS in risk stratification for thyroid lesion needs further evaluation. Aim Of this study was to evaluate ACR TI-RADS classification in discriminating benign and from other thyroid lesions as detected by fine needle aspiration cytology (FNAC). Methods This retrospective study included all patients referred to our institute for FNAC of a thyroid nodule over 1 year. Thyroid nodules were categorized according to the 2017 ACR TI-RADS. Ultimately, efficacy of ACR TI-RADS in differentiating benign from non-benign nodules was assessed using ROC curve, cross-tabulation, and Chisquare tests. According to the results of FNAC, nodules were classified into 2 groups; benign lesions (Bethesda II) and malignant lesions (Bethesda IV, V). Results The percentages of Bethesda IV and V lesions defined in our ACR-TIRADS were as follows: ACR TI-RADS 1, 2 (0%), ACR TI-RADS 3 (4%), ACR TI-RADS 4 (6.6%), and ACR TI-RADS 5 (22.6%). ROC curve analysis for ACR TI-RADS to differentiate benign from non-benign pathology showed (AUC 0.60, 95% CI: 0.505–0.713). ACR TI-RADS had sensitivity, specificity, positive predictive value and negative predictive value 75%, 62.35 %, 15.7%, 96.3% respectively. Conclusion Differentiation between benign and malignant thyroid lesion can be suggested from the ultrasound based ACR TI-RADS system. FNAC might be deferred in patients having ACR TI-RADS 1 and 2.
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Sun, Yu, Qingping Liu, Zhenglei Yu, Luquan Ren, Xin Zhao e Jincheng Wang. "Study on Osseointegration Capability of β-Type Ti–Nb–Zr–Ta–Si Alloy for Orthopedic Implants". Materials 17, n.º 2 (19 de janeiro de 2024): 472. http://dx.doi.org/10.3390/ma17020472.
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Osseointegration is the basic condition for orthopedic implants to maintain long-term stability. In order to achieve osseointegration, a low elastic modulus is the most important performance indicator. It is difficult for traditional titanium alloys to meet this requirement. A novel β-titanium alloy (Ti–35Nb–7Zr–5Ta)98Si2 was designed, which had excellent strength (a yield strength of 1296 MPa and a breaking strength 3263 MPa), an extremely low elastic modulus (37 GPa), and did not contain toxic elements. In previous in vitro studies, we confirmed the good biocompatibility of this alloy and similar bioactivity to Ti-6Al-4V, but no in vivo study was performed. In this study, Ti-6Al-4V and (Ti–35Nb–7Zr–5Ta)98Si2 were implanted into rabbit femurs. Imaging evaluation and histological morphology were performed, and the bonding strength and bone contact ratio of the two alloys were measured and compared. The results showed that both alloys remained in their original positions 3 months after implantation, and neither imaging nor histological observations found inflammatory reactions in the surrounding bone. The bone–implant contact ratio and bonding strength of (Ti–35Nb–7Zr–5Ta)98Si2 were significantly higher than those of Ti-6Al-4V. The results confirmed that (Ti–35Nb–7Zr–5Ta)98Si2 has a better osseointegration ability than Ti-6Al-4V and is a promising material for orthopedic implants.
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Wang, Guangshun, Karen M. Watson, Alan Peterkofsky e Robert W. Buckheit. "Identification of Novel Human Immunodeficiency Virus Type 1-Inhibitory Peptides Based on the Antimicrobial Peptide Database". Antimicrobial Agents and Chemotherapy 54, n.º 3 (19 de janeiro de 2010): 1343–46. http://dx.doi.org/10.1128/aac.01448-09.
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ABSTRACT To identify novel anti-HIV-1 peptides based on the antimicrobial peptide database (APD; http://aps.unmc.edu/AP/main.php ), we have screened 30 candidates and found 11 peptides with 50% effective concentrations (EC50) of <10 μM and therapeutic indices (TI) of up to 17. Furthermore, among the eight peptides (with identical amino acid compositions but different sequences) generated by shuffling the sequence of an aurein 1.2 analog, two had a TI twice that of the original sequence. Because antiviral peptides in the database have an arginine/lysine (R/K) ratio of >1, increases in the Arg contents of amphibian maximin H5 and dermaseptin S9 peptides and the database-derived GLK-19 peptide improved the TIs. These examples demonstrate that the APD is a rich resource and a useful tool for developing novel HIV-1-inhibitory peptides.
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Wang, Xiao Peng, Yu Yong Chen, Fan Tao Kong e Shu Long Xiao. "Effect of HA Content on Microstructure and Compression Properties of Ti-Nb-Sn/HA Composites Fabricated by Plasma Current Activated Sintering". Materials Science Forum 816 (abril de 2015): 705–10. http://dx.doi.org/10.4028/www.scientific.net/msf.816.705.
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Novel bio-composites were synthesized by plasma current activated sintering from the Ti-35Nb-2.5Sn/HA powders ball-milled for 12 h. The aim of this study was to investigate the effects of HA content (5, 10 and 15 wt%) on sintering properties, microstructure and compression properties of Ti-35Nb-2.5Sn/HA bio-composites. Results indicated that sintering rate decreased slightly with the increase of HA content. The phases of sintered composites were mainly˰ڂ˽̤̹˼˰̘̑˼˰Ca3(PO4)2(TCP), TiO2, CaTiO3and TixPy. The grain size of sintered composites reduced with the increasing of HA content, and sintered composites with ultra fine grains were fabricated finally. The compression test showed that all the sintered composites had low elastic modulus and high compression strength. The elastic modulus of Ti-35Nb-2.5Sn/15HA sintered composites was 22GPa with a high strength of 877MPa.
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Jasim, Sundus, Zahraa Hussien Khalaf e Nawal Mohammed Dawood. "Effect of Si Content on Microstructure and Mechanical Behavior of Porous Ti-22 at% Nb Shape Memory Alloys for Biomedical Applications". Materials Science Forum 1089 (26 de maio de 2023): 109–19. http://dx.doi.org/10.4028/p-s028cu.
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Our research novel Ti-22Nb biomedical alloys made by powder metallurgy and analyze the effect of adding silicon at various weight ratios to the base alloy (0.4, 0.8, and 1.2 %at Si). In this work, the wear characteristics of Ti-Nb-Si alloys in dry conditions are examined, as well as the wear process. To measure the wear rate, a pin-on-disc wear testing apparatus was employed. The optical microstructure analysis showed that the microstructure had a mixture-like appearance and included only a small quantity of another phase. XRD results showed that the stability of the β phase increased with silicon concentration. The (Ti-22Nb) alloy's hardness and compressive strength both increased once silicon is added. Hardness also rises as the amount of silicon additions increases, with the maximum percentage (1.2 percent Si) resulting in the highest hardness and compressive strength
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Di Maio, Attilio, Hamza Olleik, Elise Courvoisier-Dezord, Sophie Guillier, Fabienne Neulat-Ripoll, Romain Haudecoeur, Jean-Michel Bolla et al. "Design and Synthesis of Novel Amino and Acetamidoaurones with Antimicrobial Activities". Antibiotics 13, n.º 4 (26 de março de 2024): 300. http://dx.doi.org/10.3390/antibiotics13040300.
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The development of new and effective antimicrobial compounds is urgent due to the emergence of resistant bacteria. Natural plant flavonoids are known to be effective molecules, but their activity and selectivity have to be increased. Based on previous aurone potency, we designed new aurone derivatives bearing acetamido and amino groups at the position 5 of the A ring and managing various monosubstitutions at the B ring. A series of 31 new aurone derivatives were first evaluated for their antimicrobial activity with five derivatives being the most active (compounds 10, 12, 15, 16, and 20). The evaluation of their cytotoxicity on human cells and of their therapeutic index (TI) showed that compounds 10 and 20 had the highest TI. Finally, screening against a large panel of pathogens confirmed that compounds 10 and 20 possess large spectrum antimicrobial activity, including on bioweapon BSL3 strains, with MIC values as low as 0.78 µM. These results demonstrate that 5-acetamidoaurones are far more active and safer compared with 5-aminoaurones, and that benzyloxy and isopropyl substitutions at the B ring are the most promising strategy in the exploration of new antimicrobial aurones.
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Komarova, Ekaterina G., Yurii P. Sharkeev, Mariya B. Sedelnikova, Konstantin A. Prosolov, Igor A. Khlusov, Oleg Prymak e Matthias Epple. "Zn- or Cu-Containing CaP-Based Coatings Formed by Micro-arc Oxidation on Titanium and Ti-40Nb Alloy: Part I—Microstructure, Composition and Properties". Materials 13, n.º 18 (16 de setembro de 2020): 4116. http://dx.doi.org/10.3390/ma13184116.
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Zn- and Cu-containing CaP-based coatings, obtained by micro-arc oxidation process, were deposited on substrates made of pure titanium (Ti) and novel Ti-40Nb alloy. The microstructure, phase, and elemental composition, as well as physicochemical and mechanical properties, were examined for unmodified CaP and Zn- or Cu-containing CaP coatings, in relation to the applied voltage that was varied in the range from 200 to 350 V. The unmodified CaP coatings on both types of substrates had mainly an amorphous microstructure with a minimal content of the CaHPO4 phase for all applied voltages. The CaP coatings modified with Zn or Cu had a range from amorphous to nano- and microcrystalline structure that contained micro-sized CaHPO4 and Ca(H2PO4)2·H2O phases, as well as nano-sized β-Ca2P2O7, CaHPO4, TiO2, and Nb2O5 phases. The crystallinity of the formed coatings increased in the following order: CaP/TiNb < Zn-CaP/TiNb < Cu-CaP/TiNb < CaP/Ti < Zn-CaP/Ti < Cu-CaP/Ti. The increase in the applied voltage led to a linear increase in thickness, roughness, and porosity of all types of coatings, unlike adhesive strength that was inversely proportional to an increase in the applied voltage. The increase in the applied voltage did not affect the Zn or Cu concentration (~0.4 at%), but led to an increase in the Ca/P atomic ratio from 0.3 to 0.7.
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Gao, Min, Tijun Chen e He Qin. "Effects of Mold Temperature on the Microstructure and Tensile Properties of Ti@(Al-Si-Ti)p/A356 Composite Prepared via Powder Thixoforming". Metals 8, n.º 10 (15 de outubro de 2018): 829. http://dx.doi.org/10.3390/met8100829.
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A novel A356 Al-based composite reinforced with Ti@(Al-Si-Ti) core-shell-structured particles (Ti@(Al-Si-Ti)p) was prepared utilizing powder thixoforming method. The effects of mold temperature on the microstructures and tensile properties of the composites, as well as the toughening mechanisms, were investigated. The results indicated that the primary α-Al particles gradually coarsened and evolved into large-sized interconnected particles with the rise of mold temperature. Simultaneously, the core-shell structured reinforcements tended to agglomerate and the eutectic Si phases gradually coarsened and became spheroidal. The tensile properties of the synthesized composites firstly increased as the mold temperature rose from 150 °C to 200 °C due mainly to the improvement of the microstructure compactness and the spheroidization of the eutectic Si phases, and then decreased resulting from the coarsening of both the primary particles and eutectic Si phases, the agglomeration of the reinforcing particles and the deteriorated microstructure compactness. The composite thixoformed at 200 °C had an excellent elongation of 8.3% besides high tensile strengths. The excellent ductility can be attributed to decreased crack size in the shell and delayed crack propagation by plastic deformation, and multiplication of secondary cracks in the Ti core that originated from the core-shell structure of the reinforcements.
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Jiang, Bicun, Fuqiang Liu, Yang Pan, Yan Tan, Chendong Shuang e Aimin Li. "Preparation of Graphite-UiO-66(Zr)/Ti electrode for efficient electrochemical oxidation of tetracycline in water". PLOS ONE 17, n.º 8 (9 de agosto de 2022): e0271075. http://dx.doi.org/10.1371/journal.pone.0271075.
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Tetracycline (TC) is widely-used antibiotic pollutant with high toxicity, refractory, persistence and bacteriostasis, and its removal from water needs to be enhanced. In this work, a novel Graphite-UiO-66(Zr)/Ti electrode was successfully prepared and evaluated for electrochemical oxidation degradation of TC. The electrochemical performance tests indicate the Graphite-UiO-66(Zr)/Ti electrode had higher electrochemical oxidation activity, which achieved higher TC removal efficiency (98.1% ± 1.5%) than Ti plate (65.2% ± 3.5%), Graphite-MIL-53(Al)/Ti electrode (79.5% ± 2.9%) and Graphite-MIL-100(Fe)/Ti electrode (89.0% ± 2.6%). The influence of operating condition was also systematically studied, and the optimized condition was pH 5.0, 20 mA/cm2 current density and 0.1 M electrolyte (Na2SO4). Through the liquid chromatography mass spectrometry (LC-MS), the TC degradation pathway by Graphite-UiO-66(Zr)/Ti electrode oxidation was proposed. Under the •OH free radical oxidative decomposition effect, the double bond, phenolic group and amine group of TC were attacked. TC was transformed into intermediate product ① (m/z = 447), then was further degraded to intermediates ② (m/z = 401) and ③ (m/z = 417). The latter was fragmented into small fractions ④ (m/z = 194), ⑤but-2-enedioic acid (m/z = 116) and ⑥oxalic acid (m/z = 90, the proposed intermediate). In addition, TC removal remained at 89.6% ± 2.7% in the sixth cycle of operation, which confirmed the efficient reusability and stability for antibiotics removal from water.
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DONG, QING, CHUANZHONG CHEN, DIANGANG WANG e QIANMAO JI. "PREPARATION AND MICROSTRUCTURE OF THIN TiO2 FILMS CONTAINING Ca AND P USING MICRO-ARC OXIDATION". Surface Review and Letters 12, n.º 04 (agosto de 2005): 555–59. http://dx.doi.org/10.1142/s0218625x05007426.
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Micro-arc oxidation (MAO) is a novel technique for producing oxide films on metals like Al , Mg , Ti and Zr . A ceramic-like film containing Ca and P was deposited on Ti-6Al-4V substrate by MAO in an electrolytic solution using a pulsed power supply. XRD indicated that the film was a mixture of anatase, rutile and VO. SEM showed that the surface of the film was microporous with 1–2 μm pores. EDS gave the element distributions of the cross-section. The result indicated that elements like Ca and P could be incorporated into the film during MAO process. The microhardness test showed that the film had an average hardness of 540 HV0.025.
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Chang, Yuh Ping, Ruei Hong Wang, Yu Yang Hung, Huann Ming Chou e Jin Chi Wang. "Electrical Contact Resistance Approach to Tribological Properties of Artificial Joints". Materials Science Forum 594 (agosto de 2008): 383–88. http://dx.doi.org/10.4028/www.scientific.net/msf.594.383.
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The tribo-electrification mechanisms had been successfully applied to dynamic monitor the tribological properties between the metal films by our laboratory members. Moreover, the novel method of using continuous tribo-electrification variations for monitoring showed more sensitive and discriminative than that by the continuous friction coefficient variations as usual. However, the above method is only suitable for the conducted material pairs. This study is based on the above views to further develop another novel method for dynamic monitoring the tribological properties between the semiconductor films in the friction process. The experiment was conducted by the self-developed friction tester and its measure system. The continuous variations of electrical contact resistance and friction coefficient were measured for monitoring the timings of film rupture between the semiconductor films. Moreover, the wear loss was measured by an accuracy balance and the SEM was used to observe the structures of material transfer. Therefore, the wear mechanisms of Ti sliding against Ti with TiO2-film under different normal loads can be investigated. According to the experimental results of this study, the novel method of using electrical contact resistance variations does show great potentialities for dynamic monitoring the tribological properties of the TiO2-film.
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O'Callaghan, Dermot S., Elton Rexhepaj, Kathy Gately, Linda Coate, David Delaney, Dearbhaile M. O'Donnell, Elaine Kay, Finbarr O'Connell, William M. Gallagher e Kenneth J. O'Byrne. "Tumour islet Foxp3+ T-cell infiltration predicts poor outcome in nonsmall cell lung cancer". European Respiratory Journal 46, n.º 6 (5 de novembro de 2015): 1762–72. http://dx.doi.org/10.1183/13993003.00176-2014.
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The impact of host immunity on outcome in nonsmall cell lung cancer (NSCLC) is controversial. We examined the relationship between lymphoid infiltration patterns in NSCLC and prognosis.Tumour- and stroma-infiltrating CD3+, CD8+ and forkhead box P3 (Foxp3)+ T-lymphocytes were identified using immunohistochemistry and a novel image analysis algorithm to assess total, cytotoxic and regulatory T-lymphocyte counts, respectively, in 196 NSCLC cases. The median cell count was selected as a cut-point to define patient subgroups and the ratio of the corresponding tumour islet:stroma (TI/S) counts was determined.There was a positive association between overall survival and increased CD8+ TI/S ratio (hazard ratio (HR) for death 0.44, p<0.001) but an inverse relationship between Foxp3+ TI/S ratio and overall survival (HR 4.86, p<0.001). Patients with high CD8+ islet (HR 0.48, p<0.001) and Foxp3+ stromal (HR 0.23, p<0.001) counts had better survival, whereas high CD3+ and CD8+ stromal counts and high Foxp3+ islet infiltration conferred a worse survival (HR 1.55, 2.19 and 3.14, respectively). By multivariate analysis, a high CD8+ TI/S ratio conferred an improved survival (HR 0.48, p=0.002) but a high Foxp3+ TI/S ratio was associated with worse survival (HR 3.91, p<0.001).Microlocalisation of infiltrating T-lymphocytes is a powerful predictor of outcome in resected NSCLC.
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Zhang, Shidong, Guang Jiang, Yang Yang, Hongtao Li, Fuyao Yan, Mufu Yan e Yanxiang Zhang. "Annealing Effect on Microstructure of Novel Ti Doped DLC Multilayer Films". Coatings 13, n.º 5 (26 de abril de 2023): 833. http://dx.doi.org/10.3390/coatings13050833.
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Diamond-like films (DLC) are an exceptional engineering material with excellent performance such as high hardness, low friction coefficient, superior wear resistance and chemical inertness. However, two major problems of high internal stress and poor thermal stability have seriously limited its industrial applications. In particular, the microstructures and properties of pure DLC films are highly sensitive to high temperature. Therefore, the purpose of this study is to investigate the effect of annealing temperature on the microstructures of the as-prepared films. Ti-doped DLC multilayer films were synthesized by closed field unbalanced magnetron sputtering. The as-deposited films were annealed in the range of 200 to 800 °C. The surface morphology, phase structure and bonding structure of the films were characterized by SEM, AFM, GIXRD and Raman spectroscopy. The resulting films remained a smooth surface after annealing and maintained the nature of amorphous carbon up to 600 °C. The formed phases of graphite carbon and TiC nanocrystallines occur above 600 °C. In addition, the D- and G-bands showed a significant blue shift and the FWHMG shows a declining trend up to 600 °C. This result revealed that the films had high graphitization temperature and good thermal stability due to the formation of TiC nanocrystallines and its novel structure design containing elemental doping, multilayer structuring and functionally graded layering.
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Nunes, Aline Raquel Vieira, Sinara Borborema, Leonardo Sales Araújo, Luiz Henrique de de Almeida e Michael J. Kaufman. "Production of a Novel Biomedical β-Type Titanium Alloy Ti-23.6Nb-5.1Mo-6.7Zr with Low Young’s Modulus". Metals 12, n.º 10 (24 de setembro de 2022): 1588. http://dx.doi.org/10.3390/met12101588.
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Metastable β titanium alloys are developed for biomedical applications due to their low Young’s moduli and functional properties. These alloys can be fitted to different parts of orthopedic implants through thermomechanical processing and chemical composition control. This study aimed to produce, process, and characterize a new metastable β titanium Ti-23.6Nb-5.1Mo-6.7Zr alloy on a semi-industrial scale for orthopedic implant manufacturing, and to discuss the influence of the cold rolling and transformed phases during aging in the microstructure and mechanical properties. This alloy was produced in a vacuum arc remelting furnace (VAR) and thermomechanically processed under different conditions. The samples were characterized by X-ray diffractometry, optical, and scanning electron microscopy, and Young’s modulus (YM) and Vickers Hardness (HV) tests. Among other processing conditions, the sample that was 50% cold rolled after solution treatment, which resulted in a microstructure with β and α″ phases, had the lowest YM (~57 GPa), and the sample aged at 300 °C for 2 h had the highest HV/YM ratio (5.42). The new alloy produced in this work, processed by different routes, showed better mechanical properties than most recently developed metastable Ti-β Alloys.
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Ashton, J., G. Cheng, I. Stafford, R. M. Beattie e S. Ennis. "DOP64 Utilising genomics to predict outcomes and delineate novel subgroups in inflammatory bowel disease". Journal of Crohn's and Colitis 17, Supplement_1 (30 de janeiro de 2023): i137—i140. http://dx.doi.org/10.1093/ecco-jcc/jjac190.0104.
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Abstract Background The rise of ‘big data’ in inflammatory bowel disease (IBD) presents an opportunity to improve understanding of pathogenesis and unpick the molecular complexity of this heterogenous condition. Personalisation of IBD management relies on predicting outcomes, response to therapy and prevention of complications. Here, we present results outlining subgrouping of patients and outcome prediction using multiomic/clinical data. Methods Using whole exome sequencing from 1100 patients in the Southampton IBD cohort, including 650 paediatric cases, we have performed iterative studies focused on 1) Impact of genomic variation across the NOD-signaling pathway measured by perturbation of transcription across multiple genes, 2) Development of NOD2 as a genomic biomarker of stricturing Crohn’s disease (CD), 3) Utilising machine learning and genomic data to develop disease classification models. These data utilise GenePy, a tool developed in house that summarises genomic variation to give a per individual, per gene deleteriousness metric. Results Within the NOD-signaling pathway patients harbouring deleterious variation in NOD2 had reduced NOD2 expression and increased NFKBIA expression, reflecting reduced NFKB signaling, figure 1A. We report deleterious variation in several key complexes including NOD2-RIPK2 and TAK1-TAB, resulted in reduced transcription of NFKB activators and alternative inflammatory pathway activation, figure 1C-D. Utilising genomic data we constructed a NOD2 prediction model for stricturing disease in Crohn’s disease; 56.7% of patients in the ‘high-risk group’ had stricturing behaviour, whilst in the low-risk group only 21.4% had strictures. Addition of terminal ileal (TI) disease to the NOD2 risk groups significantly improved prediction, figure 2A. Using survival modelling, high-risk group paediatric patients presenting with TI disease had a HR of 4.89 (P = 2.3×10-5) compared with the low-risk group patients without TI disease, figure 2B. Finally, we used supervised machine learning of genomic data to classify patients with CD or ulcerative colitis. We employed different gene lists and assessed how accurately we could assign patients to their diagnosis. An autoimmune gene panel produced the best model (AUROC 0.68), compared to an IBD panel (AUCROC 0.61). NOD2 was the most discriminating gene in all the gene panels. Conclusion These iterative projects demonstrate the utility of integrating genomic and clinical data to improve the subtyping of patients with IBD and provide disease prediction models. Future work will include analyses of additional inflammatory pathways and targeting different clinical outcomes. We hope clinical translation of these findings will be a step-change in precision medicine for IBD.
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Duncan, Warwick J., Sunyoung Ma, Allauddin Siddiqi e Reham B. Osman. "Zirconia versus Titanium Implants: 8-Year Follow-Up in a Patient Cohort Contrasted with Histological Evidence from a Preclinical Animal Model". Materials 15, n.º 15 (2 de agosto de 2022): 5322. http://dx.doi.org/10.3390/ma15155322.
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Zirconia ceramic (ZC) implants are becoming more common, but comparisons between preclinical histology and long-term clinical trials are rare. This investigation comprised (1) 8-year clinical follow-up of one-piece ZC or titanium (Ti) implants supporting full overdentures and (2) histomorphometric analysis of the same implants in an animal model, comparing implants with various surface treatments. Methods: (1) Clinical trial: 24 completely edentulous participants (2 groups of N = 12) received 7 implants (one-piece ball-abutment ZC or Ti; maxilla N = 4, mandible N = 3) restored with implant overdentures. Outcomes after 8-years included survival, peri-implant bone levels, soft-tissue responses, and prosthodontic issues. (2) Preclinical trial: 10 New Zealand sheep received 4 implants bilaterally in the femoral condyle: Southern Implants ZC or Ti one-piece implants, identical to the clinical trial, and controls: Southern ITC® two-piece implants with the same surface or Nobel (NBC) anodised (TiUnite™) surface. %Bone-implant contact (%BIC) was measured after 12 weeks of unloaded healing. Results: 8 of 24 participants (33%) of an average age of 75 ± 8 years were recalled; 21% of original participants had died, and 46% could not be contacted. 80.4% of implants survived; excluding palatal sites, 87.5% of Ti and 79% of ZC implants survived. All failed implants were in the maxilla. Three ZC implants had fractured. Bone loss was similar for Ti vs. ZC; pocket depths (p = 0.04) and attachment levels (p = 0.02) were greater for Ti than ZC implants. (1.7 ± 1.6 mm vs. 1.6 ± 1.3 mm). All implants in sheep femurs survived. %BIC was not statistically different for one-piece blasted surface Ti (80 ± 19%) versus ZC (76 ± 20%) or ITC® (75 ± 16 mm); NBC had significantly higher %BIC than ITC (84 ± 17%, p = 0.4). Conclusion: Short-term preclinical results for ZC and Ti one-piece implants showed excellent bone-implant contact in unloaded femoral sites. This differed from the long-term clinical results in older-aged, edentulous participants. While ZC and Ti implants showed equivalent performance, the risks of peri-implantitis and implant loss in older, completely edentulous patients remain a significant factor.
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Fowler, Lee, Arno Janse Van Vuuren, William Goosen, Håkan Engqvist, Caroline Öhman-Mägi e Susanne Norgren. "Investigation of Copper Alloying in a TNTZ-Cux Alloy". Materials 12, n.º 22 (8 de novembro de 2019): 3691. http://dx.doi.org/10.3390/ma12223691.
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Alloying copper into pure titanium has recently allowed the development of antibacterial alloys. The alloying of biocompatible elements (Nb, Ta and Zr) into pure titanium has also achieved higher strengths for a new alloy of Ti-1.6 wt.% Nb-10 wt.% Ta-1.7 wt.% Zr (TNTZ), where strength was closer to Ti-6Al-4V and higher than grade 4 titanium. In the present study, as a first step towards development of a novel antibacterial material with higher strength, the existing TNTZ was alloyed with copper to investigate the resultant microstructural changes and properties. The initial design and modelling of the alloy system was performed using the calculation of phase diagrams (CALPHAD) methods, to predict the phase transformations in the alloy. Following predictions, the alloys were produced using arc melting with appropriate heat treatments. The alloys were characterized using energy dispersive X-ray spectroscopy in scanning transmission electron microscopy (STEM-EDS) with transmission Kikuchi diffraction (TKD). The manufactured alloys had a three-phased crystal structure that was found in the alloys with 3 wt.% Cu and higher, in line with the modelled alloy predictions. The phases included the α-Ti (HCP-Ti) with some Ta present in the crystal, Ti2Cu, and a bright phase with Ti, Cu and Ta in the crystal. The Ti2Cu crystals tended to precipitate in the grain boundaries of the α-Ti phase and bright phase. The hardness of the alloys increased with increased Cu addition, as did the presence of the Ti2Cu phase. Further studies to optimize the alloy could result in a suitable material for dental implants.
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Xu, Mai, Chunli Gao, Xiaoyan Zhang, Xian Liang, Yunhu Hu e Fengwu Wang. "Development of SDS-Modified PbO2 Anode Material Based on Ti3+ Self-Doping Black TiO2NTs Substrate as a Conductive Interlayer for Enhanced Electrocatalytic Oxidation of Methylene Blue". Molecules 28, n.º 19 (9 de outubro de 2023): 6993. http://dx.doi.org/10.3390/molecules28196993.
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Efficient and stable electrode materials are urgently required for wastewater treatment in the electrocatalytic degradation of toxic and refractory organic pollutants. Ti3+ self-doping black TiO2 nanotube arrays (Ti/B-TiO2-NTs) as an interlayer were used for preparing a novel PbO2 electrode via an electrochemical reduction technology, and a sodium dodecyl sulfate (SDS)-modified PbO2 catalytic layer was successfully achieved via an electrochemical deposition technology. The physicochemical characterization tests showed that the Ti/B-TiO2-NTs/PbO2-SDS electrodes have a denser surface and finer grain size with the introduction of Ti3+ in the interlayer of Ti/TiO2-NTs and the addition of SDS in the active layer of PbO2. The electrochemical characterization results showed that the Ti3+ self-doping black Ti/TiO2-NTs/PbO2-SDS electrode had higher oxygen evolution potential (2.11 V vs. SCE), higher electrode stability, smaller charge-transfer resistance (6.74 Ω cm−2), and higher hydroxyl radical production activity, leading to it possessing better electrocatalytic properties. The above results indicated that the physicochemical and electrochemical characterization of the PbO2 electrode were all enhanced significantly with the introduction of Ti3+ and SDS. Furthermore, the Ti/B-TiO2-NTs/PbO2-SDS electrodes displayed the best performance on the degradation of methylene blue (MB) in simulated wastewater via bulk electrolysis. The removal efficiency of MB and the chemical oxygen demand (COD) could reach about 99.7% and 80.6% under the optimal conditions after 120 min, respectively. The pseudo-first-order kinetic constant of the Ti/B-TiO2-NTs/PbO2-SDS electrode was 0.03956 min−1, which was approximately 3.18 times faster than that of the Ti/TiO2-NTs/PbO2 electrode (0.01254 min−1). In addition, the Ti/B-TiO2-NTs/PbO2-SDS electrodes showed excellent stability and reusability. The degradation mechanism of MB was explored via the experimental identification of intermediates. In summary, the Ti3+ self-doping black Ti/TiO2-NTs/PbO2-SDS electrode is a promising electrode in treating wastewater.
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Jia, Xiaoyu, Darren Richard Feldman, Ilya Glezerman, Lindsay Joy Van Alstine, Dean F. Bajorin, Patricia Fischer, Amanda Hughes et al. "Phase I/II study of paclitaxel plus ifosfamide (TI) followed by high-dose paclitaxel, ifosfamide, and carboplatin (TIC) with autologous stem cell transplant (ASCT) for salvage treatment of germ cell tumors (GCT)." Journal of Clinical Oncology 31, n.º 15_suppl (20 de maio de 2013): 4534. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.4534.
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4534 Background: High-dose chemotherapy (HDCT) can achieve durable remissions in 30-60% of GCT patients (pts) requiring salvage treatment. This Phase I/II study investigated safety and efficacy of a novel high-dose regimen (TI-TIC) in this population. Methods: Pts age ≥18 with GCT and progression after ≥1 cisplatin-based regimen were eligible. TI-TIC consists of 1-2 cycles of conventional-dose paclitaxel plus ifosfamide (TI) q14-21 days followed by 3 cycles of high-dose TIC with ASCT q21-28 days. TI dosing was constant. In Phase I, high-dose TIC was administered in 1 of 5 cohorts (I: 6, 8 or 10g/m2; T: 200 or 250mg/m2; C: AUC=21 or 24) using a standard 3+3 dose escalation design to determine the maximal tolerated dose (MTD). In Phase II, Simon’s 2-stage optimal design was used to estimate the complete response (CR) rate at MTD. Results: Of 26 pts (25 male; median age 31; 21 nonseminoma, 5 seminoma) enrolled, 23 received ≥1 cycle of high-dose TIC. Primary sites included testis (n=15), mediastinum (n=6), other (5). In Phase I, 0/18 pts had dose-limiting toxicity (DLT) during TIC cycle 1, making cohort 5 (T 250mg/m2, I 10g/m2, C AUC=24) the MTD. Toxicities were similar to those reported with TI-CE (Feldman JCO 2010) with little variation across cohorts. However, 2/18 pts in Phase I (1 in cohort 4, 1 in cohort 5) developed grade 3 acute renal insufficiency after cycles 1 and 2 (cycle 3 not given). Both later developed chronic renal insufficiency with 1 pt requiring dialysis 10 months after TI-TIC. A third pt treated in Phase II developed a similar acute and then chronic renal insufficiency pattern with TIC cycles 1 and 2. In Phase II, 7/11 evaluable pts (64%, 90% one-sided CI 40%-100%) achieved a CR, 1 had a partial response with negative markers, and 3 had incomplete responses. Although the CR rate was sufficient to move to the second Simon’s stage, renal toxicity led to premature trial closure. Conclusions: Although there was preliminary evidence of efficacy, high dose TI-TIC was associated with acute and chronic renal insufficiency. TI-CE remains the standard high dose regimen for salvage treatment of GCT at MSKCC. Clinical trial information: NCT00423852.
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Peng, Ben, Long Wu, Jin-Hui Zhu, Yong Hou e Guo-Hua Zhang. "A novel method for preparing Ti5Si3 from Ti-bearing blast furnace slag". Metallurgical Research & Technology 117, n.º 6 (2020): 614. http://dx.doi.org/10.1051/metal/2020073.
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Effective recovery of titanium resources from titanium-bearing blast furnace slag had always been a difficult problem. In the present study, Ti5Si3 was synthesized via silicothermic reduction of titanium-bearing blast furnace slag. The effects of reduction temperature and reaction time on the formation of Ti5Si3 were studied by X-ray diffraction and scanning electron microscope. The results indicated that Ti5Si3 was the only silicide in the finally obtained products. Ti5Si3 will gradually sinter to form a porous skeleton, and a small amount of slag will be trapped in the porous skeleton of Ti5Si3. It provided a feasible route for the treatment of titanium-bearing blast furnace slag and the recovery of titanium resources. It was also found that the longer the reaction time and the higher the reaction temperature (1823 K), the less the slag trapped in the alloy will be.
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Gao, Jing, Junjuan Yan, Youzhi Liu, Jiacheng Zhang e Zhiyuan Guo. "A novel electro-catalytic degradation method of phenol wastewater with Ti/IrO2-Ta2O5 anodes in high-gravity fields". Water Science and Technology 76, n.º 3 (4 de maio de 2017): 662–70. http://dx.doi.org/10.2166/wst.2017.262.
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In the electro-catalytic degradation process of phenol wastewater, bubbles and mass transfer limitation will result in the decrease in wastewater degradation efficiency, a long electrolysis time and a high energy consumption. Self-made Ti/IrO2-Ta2O5 anodes and a high-gravity electro-catalytic reactor were used to improve them. The Ti/IrO2-Ta2O5 anode was prepared with a thermal decomposition method and characterized by scanning electron microscopy (SEM). Under optimum conditions, the removal efficiencies of phenol, total organic carbon (TOC) and chemical oxygen demand (COD) respectively reached 94.77%, 50.96% and 41.2% after 2 h electrolysis in the high-gravity field, which were respectively 10.93%, 16.72% and 24.84% higher than those in the normal gravity field. For about the same removal efficiencies, the electrolysis time and energy consumed in the high-gravity field were 33.3% and 15.4% lower than those consumed in the normal gravity field, respectively. The degradation pathway of phenol detected by high performance liquid chromatography (HPLC) was unchanged in the high-gravity field, but the degradation rate of phenol increased. The Ti/IrO2-Ta2O5 anode provided good stability because the removal efficiencies of phenol and TOC decreased slightly and the surface morphology of the coating was almost unchanged when it had been used in electrolysis for 11 months, about 1,200 h, in the high-gravity field. Results indicated that the phenol wastewater degradation efficiency was improved, the time was shortened, and the energy consumption was reduced in the high-gravity field.
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Hsu, Cheng-Hsun, Chun-Yin Lin e Jian-Xun Chen. "Wear and Corrosion Performance of Ti-6Al-4V Alloy Arc-Coated TiN/CrN Nano-Multilayer Film". Metals 13, n.º 5 (7 de maio de 2023): 907. http://dx.doi.org/10.3390/met13050907.
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The objective of this study was to investigate the effect of varying bias parameters (−50 V, −100 V, and −150 V) on the properties of TiN/CrN multilayer films deposited on Ti-6Al-4V alloy using the cathodic arc deposition (CAD) technique. The deposited films were characterized for their composition, structure, morphology, thickness, adhesion, and hardness. Wear and polarization tests were also conducted to determine the optimal bias condition for wear and corrosion resistance. The results showed that the TiN/CrN films possessed a nano-multilayered structure comprising TiN and CrN phases. The hard coating significantly increased the surface hardness of Ti-6Al-4V alloy up to three–five times. The coated specimens demonstrated superior wear resistance compared to the uncoated, with the −150 V specimen exhibiting the least wear rate. Furthermore, the −150 V specimen had the highest polarization impedance value, indicating the best corrosion resistance compared to the other bias conditions. In short, the use of CAD-coated TiN/CrN multilayer film enhanced the surface properties of Ti-6Al-4V alloy, with the best wear and corrosion resistance achieved at −150 V bias. These novel findings have significant implications for improving the performance and durability of Ti-6Al-4V alloy components in various industrial applications.
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Wang, Yihao, Limin Jia, Erhu Yan, Zhijie Guo, Shuo Zhang, Tangwei Li, Yongjin Zou et al. "Phase Equilibria of the V-Ti-Fe System and Its Applications in the Design of Novel Hydrogen Permeable Alloys". Membranes 13, n.º 10 (27 de setembro de 2023): 813. http://dx.doi.org/10.3390/membranes13100813.
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The precise liquidus projection of the V-Ti-Fe system are crucial for designing high-performance hydrogen permeation alloys, but there are still many controversies in the research of this system. To this end, this article first uses the CALPHAD (CALculation of PHAse Diagrams) method to reconstruct the alloy phase diagram and compares and analyses existing experimental data, confirming that the newly constructed phase diagram in this article has good reliability and accuracy. Second, this obtained phase diagram was applied to the subsequent development process of hydrogen permeation alloys, and the (Ti65Fe35)100−xVx (x = 0, 2.5, 5, 10, 15, 25) alloys with dual-phase {bcc-(V, Ti) + TiFe} structure were successfully explored. In particular, the alloys with x values equal to 2.5 at.% and 5 at.% exhibit relatively high hydrogen permeability. Third, to further increase the H2 flux permeation through the alloys, a 500-mm-long tubular (Ti65Fe35)95V5 membrane for hydrogen permeation was prepared for the first time. Hydrogen permeation testing showed that this membrane had a very high H2 flux (4.06 mL min−1), which is ca. 6.7 times greater than the plate-like counterpart (0.61 mL min−1) under the same test conditions. This work not only indicates the reliability of the obtained V-Ti-Fe phase diagram in developing new hydrogen permeation alloys, but also demonstrates that preparing tubular membranes is one of the most important means of improving H2 flux.
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Chikwanda, Hilda, e L. Mahlatji. "Mechanical Alloying of Ti-Based Materials". Key Engineering Materials 770 (maio de 2018): 95–105. http://dx.doi.org/10.4028/www.scientific.net/kem.770.95.
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Mechanical alloying (MA) is a simple and versatile dry powder processing technique that has been used for the manufacture of both equilibrium and metastable phases of commercially useful and scientifically interesting materials. It owes its origin to an industry need to develop a nickel-based super alloy for gas turbine applications that had both oxide dispersion strengthening and precipitation hardening. This far-from equilibrium powder metallurgy processing technique involves fracturing, welding and re-welding of powder particles in a High Energy Ball Mill (HEBM). MA is an economically viable process with important technical advantages. Its utmost advantage is in the synthesis of novel alloys, e.g., alloying of ordinarily immiscible elements, that is not possible by any other technique. As MA is a completely solid-state processing technique, the limitations imposed by phase diagrams do not apply to it. The MA process is capable of producing different types of metastable effects in a variety of alloy systems. Some of the metastable effects achieved by MA are solid solution formation and amorphisation. MA has the possibility of producing superior and enhanced materials than those produces by conventional methods. In this work a review of MA and its present and potential applications for Ti-based materials are presented.
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Tan, Y. K., C. Hong, H. LI, J. C. Allen e J. Thumboo. "AB1328 A FEASIBILITY STUDY ON A NOVEL COMBINED THERMAL IMAGING AND CLINICAL JOINT ASSESSMENT APPROACH USING ULTRASOUND DETECTED JOINT INFLAMMATION OUTCOMES IN RHEUMATOID ARTHRITIS". Annals of the Rheumatic Diseases 81, Suppl 1 (23 de maio de 2022): 1770.1–1770. http://dx.doi.org/10.1136/annrheumdis-2022-eular.2.
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BackgroundThermal imaging (TI) is a portable, low cost imaging tool with high feasibility for use. Clinical joint assessment.Is routinely performed in rheumatoid arthritis (RA) patient care.ObjectivesTo assess a combined TI and clinical joint assessment (CTCA) approach in comparison with TI alone using ultrasound (US) detected joint inflammation outcomes as a gold standard.MethodsBilateral (BL) hand and wrist (22 joint sites) were assessed in this cross-sectional study. For TI (performed in a draft free room with a controlled temperature of around 22°C), the adjusted maximum (Tmax), minimum (Tmin) and average (Tavg) temperatures were derived by subtracting a control temperature (lowest Tmin at the joints per subject) from the Tmax, Tmin and Tavg per joint. US power Doppler (PD) and greyscale (GS) joint inflammation were graded semi-quantitatively (0-3) using validated scoring methods. Joint swelling and tenderness were graded as yes = 1 or no = 0. To increase the relative weightage of CTCA-MAX, CTCA-MIN and CTCA-AVG on the CTCA scores, if the joint was swollen and/or tender, the adjusted Tmax, Tmin and Tavg at each joint were multiplied by a factor of 2; otherwise, they remained unchanged. Receiver operating characteristic (ROC) analysis assessed the performance of TI and CTCA in identifying joints with US PD score > 1 and GS score > 1. A parameter was selected as a univariate predictor if statistically significant (P < 0.05) with area under the ROC curve (AUC) ≥ 0.70.ResultsThis study included 814 joints from 37 RA patients (mean disease duration, 30.9 months; mean DAS28, 4.43). For both TI and CTCA, out of the 22 joints sites, 3 joint sites were evaluated for PD score > 1 and 14 joint sites for GS score > 1; the remaining joint sites had AUC results unavailable due to small number of outcomes. For TI (Table 1), 3 joint sites had ≥ 1 predictive parameter for either PD score > 1 and/or GS score > 1 as follows: left (L) wrist and right (R) MCPJ 1, AUCs (0.813 to 0.897) for PD score > 1; L wrist and R MCPJs 1 and 3, AUCs (0.808 to 0.947) for GS score > 1. For CTCA (Table 1), 6 joint sites had ≥ 1 predictive parameter for either PD score > 1 and/or GS score > 1 as follows: BL wrists, AUCs (0.726 to 0.899) for PD score > 1; BL wrists, MCPJs 2 and 3, AUCs (0.739 to 0.931) for GS score > 1.Table 1.Identifying joints with ultrasound PD score >1 & GS score >1Thermal Imaging aloneCTCAJointUScriterionParameter (AUC ≥ 0.7& P <0.05)AUC(95% CI)Cut-offJointUScriterionParameter (AUC ≥ 0.7& P <0.05)AUC (95% CI)Cut-offLRLRLPD score >1Adjusted Tmax**0.841 (0.691, 0.992)4.7L & RPD score >1CTCA-MAX**0.899 (0.797, 1)**0.776 (0.578, .973)9.47.3WristAdjusted Tmin**0.813 (0.669, 0.958)2.85WristCTCA-MIN**0.861 (0.735, 0.987)*0.7265.74.45(0.526, 0.926)Adjusted Tavg**0.849 (0.714, 0.985)3.9CTCA-AVG**0.889 (0.781, 0.997)*0.7617.35.95(0.563, 0.959)GS score >1Adjusted Tmax**0.827 (0.687, 0.966)4.7GS score >1CTCA-MAX**0.918 (0.833, 1)**0.81387.3(0.632, 0.994)Adjusted Tmin**0.808 (0.67, 0.947)2.85CTCA-MIN**0.873 (0.761, 0.986)**0.7664.44.45(0.581, 0.951)Adjusted Tavg**0.837 (0.707, 0.967)3.9CTCA-AVG**0.913**0.8025.55.95(0.824, 1)(0.62, 0.985)RPD score >1Adjusted Tmax*0.897 (0.726, 1)5.7L & RGS score >1CTCA-MAX-*0.758-9.8(0.494, 1)MCPJ 1MCPJ 2GS score >1Adjusted Tmax*0.936 (0.813, 1)7.2CTCA-MIN*0.902*0.7392.753.9(0.775, 1)(0.443, 1)Adjusted Tmin*0.932 (0.793, 1)3.95CTCA-AVG*0.931**0.7634.75.5(0.835, 1)(0.474, 1)Adjusted Tavg*0.947 (0.868, 1)4.9L & RGS score >1CTCA-MAX*0.914*0.8736.3512.2(0.735, 1)(0.617, 1)RGS score >1Adjusted Tmax*0.922 (0.76, 1)4.6MCPJ 3CTCA-MIN-*0.902-3.15(0.75, 1)MCPJ 3CTCA-AVG-*0.902-4.1(0.728, 1)Corresponding P-value: statistically significance at *P <0.05, **P<0.01.ConclusionA novel CTCA approach helps discriminate the severity of US detected joint inflammation in RA at more joint sites when compared to TI alone; this includes the commonly affected BL wrists, MCPJs 2 and 3. Further validation work in a larger RA cohort will be required.Disclosure of InterestsNone declared
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Ahmed, Sadia T., Stevyn Fernandes, Qi Gao, Thomas J. Ow, Richard V. Smith, Bradley A. Schiff e Vikas Mehta. "Use of Predictive Modeling to Tailor Molecular Testing Utilization for Thyroid Nodules". Otolaryngology–Head and Neck Surgery 165, n.º 3 (30 de março de 2021): 406–13. http://dx.doi.org/10.1177/01945998211004155.
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Objective Various risk stratification systems for cytologically indeterminate thyroid nodules are available. However, malignancy risk assessment data, such as ultrasound features, are not always used when the decision is to order molecular testing or not. Our aim was to investigate the utility of molecular testing after incorporating an algorithm with ultrasound-based risk of malignancy (ROM) estimation. Study Design Diagnostic/prognostic study. Setting Single-institution urban tertiary care center. Methods We performed a single-institution retrospective chart review of all thyroid nodules that had undergone molecular testing. A web-based Malignancy Risk Estimation System for Thyroid Nodules was utilized with ultrasound findings to stratify malignancy risk according to the Korean Thyroid Imaging Reporting and Data System (TI-RADS), French TI-RADS, American Association of Clinical Endocrinology guideline, and American Thyroid Association guideline. A novel algorithm for utilizing molecular testing at our institution was developed with the Korean TI-RADS and with recommendations from the American Thyroid Association and National Comprehensive Cancer Network. Results The Korean TI-RADS performed best in our population (area under the curve = 0.83). A positive molecular test result had a positive association with a higher ROM according to all 4 models ( P < .05). Use of our algorithm prior to molecular testing would have prevented 38% of benign/low-ROM negative nodules (n = 28) from being tested. Conclusion In patients with indeterminate thyroid nodules, an algorithm built on pre- and posttest probability to guide molecular testing might reduce unnecessary testing of benign and low-risk nodules.
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Kirmizis, Dimitrios, Elaine Bowes, Behzad Ansari e Hugh Cairns. "Exit-Site Relocation: A Novel, Straightforward Technique for Exit-Site Infections". Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 39, n.º 4 (julho de 2019): 350–55. http://dx.doi.org/10.3747/pdi.2017.00214.
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BackgroundExit-site infection (ESI) and tunnel infection (TI) of the peritoneal dialysis (PD) catheter are significant causes of catheter or even method loss as well as patient morbidity. Among the methods that have been in use thus far, the removal and replacement of the catheter often needs to be followed by switching temporarily to hemodialysis, whereas catheter splicing or unroofing of the tunnel tract and shaving/removal of the superficial catheter cuff have not gained universal acceptance thus far.MethodsWe treat chronic ESI with exit-site relocation under local anesthetic with removal of the external cuff. For the purposes of this study, we conducted a retrospective cohort analysis of all exit-site relocations performed using that technique over a 5-year period.ResultsTwenty-seven patients (16 male, mean age 58 years, range 23 – 81 years) with chronic ESI underwent exit-site relocation under local anesthetic as a day-case procedure. Follow-up was 47.5 ± 22.4 months (range 10.8 – 79.4 months). No dialysate leaks occurred following the procedure. Peritoneal dialysis was resumed immediately. The procedure resulted in long-term resolution of the infection in 20 of the 27 patients (74%). In 7 patients (26%), the catheter had to be removed eventually, either because of ESI recurrence (5 patients) or TI (2 patients), which in 2 cases was subsequently complicated by PD peritonitis, and the patients were switched to hemodialysis.ConclusionThe technique described herein is a safe, straightforward, and effective method for the treatment of chronic ESI while the patient remains on PD and avoids switching to hemodialysis.
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Schrenk, Florian, Lorenz Lindenthal, Gernot Pacholik, Tina Navratil, Tobias Maximilian Berger, Hedda Drexler, Raffael Rameshan, Thomas Ruh, Karin Föttinger e Christoph Rameshan. "Perovskite-Type Oxide Catalysts in CO2 Utilization: A Principal Study of Novel Cu-Doped Perovskites for Methanol Synthesis". Compounds 2, n.º 4 (14 de dezembro de 2022): 378–87. http://dx.doi.org/10.3390/compounds2040031.
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Six different perovskite-type oxides were investigated with respect to their ability for methanol synthesis via H2 and CO2: Fe-, Mn-, and Ti-based perovskites were prepared with and without Cu doping. For assessment, the catalysts were subjected to preliminary tests at atmospheric pressure to evaluate their ability to activate CO2. Additional catalytic tests with the doped versions of each catalyst type were carried out in a pressured reactor at 21 bar. After the measurements, the catalysts were characterized with X-ray diffraction (XRD) and scanning electron microscopy (SEM). All catalysts were able to produce methanol in the pressure tests. CO2 conversions between 14% and 23% were reached at 400 °C, with the highest methanol selectivity at the lower temperature of 250 °C. The combination of XRD and SEM revealed that the Fe-based and Ti-based perovskites were stable under reaction conditions and that catalytically highly active and stable nanoparticles had formed. The minor formation of CaCO3, which is a deactivating phase, was observed for one catalyst. These nanoparticles showed resistance to coking and sintering. However, the yield and selectivity for methanol need to be improved via the further tailoring of the perovskite composition.
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Liu, Yiwei, Kai Chen, Tianshuo Song, Bohan Chen, Qiang Li e Chaoqun Xia. "Improvement of Mechanical Properties for a Novel Zr–Ti–V Alloy via Hot-Rolling and Annealing Treatment". Crystals 12, n.º 12 (5 de dezembro de 2022): 1765. http://dx.doi.org/10.3390/cryst12121765.
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In this experiment, an annealing treatment was carried out for a rolled Zr–Ti–8V alloy, and the toughening mechanism of the material was thoroughly analyzed by combining advanced material characterization and other testing methods. The phase composition of the Zr–Ti–8V alloy was sensitive to the applied annealing temperature, while a series of changes in the phase composition of the alloy were induced by enforcing bigger thermal budgets. Implementing a temperature value of 450 °C led to a higher α-phase content, in striking contrast with the case where a lower annealing temperature of 400 °C was applied. The β grains that were stretched in the alloy’s rolling direction and annealed at 600 °C to 800 °C were recrystallized. As a result, the acquired configuration was equiaxed with β grains. The extracted results revealed that the alloy annealed at 450 °C showed a good strong–plastic ratio, with tensile strength and elongation of 1040 MPa and 8.2%, respectively. In addition, the alloy annealed at 700–800 °C showed good plasticity properties. From the hardness tests and friction wear experiments on all the experimental alloys, it was demonstrated that the dual-phase alloy with α + β had higher hardness and wear resistance, whereas the opposite trend was observed for the single β-phase alloy.
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Munoz, Carlos Jose, Ivan Susin Pires, Andre F. Palmer, Pedro Cabrales e Srila Gopal. "Heme Scavenging with Apohemoglobin-Haptoglobin Complex in Beta Thalassemia Intermedia Improves Anemia and Iron Indices: A Novel Therapeutic Approach". Blood 138, Supplement 1 (5 de novembro de 2021): 3082. http://dx.doi.org/10.1182/blood-2021-153017.
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Abstract Beta-thalassemia intermediate (TI) is a genetic disorder of hemoglobin (Hb) synthesis characterized by anemia, ineffective erythropoiesis and iron overload. TI treatment is complex and regular transfusion therapy may be needed for growth failure, skeletal deformity, exercise intolerance, or when Hb levels decline because of progressive splenomegaly. Iron overload can be seen in TI, and serum ferritin measurement may often underestimate the extent of iron overload. There are limited therapeutic options for management of anemia and iron overload in TI. In this study, we look at the potential use of an engineered scavenger protein complex (apoHb-Hp) as a strategy to treat anemia in TI using a C57BL/6 mouse model. Sixteen beta-thalassemic mice (C57BL/6 heterozygous for the Hbb β-globin gene deletion (Hbb td3th/BrjK) (beta-thalassemia, Jackson Laboratory)) were treated with 50 µL of apoHb-Hp complex at a concentration of 27.95 mg/mL for six weeks to simultaneously scavenge cell-free Hb and free heme. Animal weight and RBC parameters (Hb, hematocrit (Hct), red blood cell (RBC) count, red cell distribution width) were measured at baseline and at 6 weeks post treatment. Total iron levels, transferrin concentration and transferrin saturation were measured at the third and sixth week of treatment. At the end of the experiment, the spleen and liver weights were measured and markers of liver function (Alanine transaminase (ALT), Aspartate transaminase (AST), Alkaline phosphatase (ALP)) were assessed. Further, total iron content of the liver and spleen was quantified using a using Perls' staining for non-heme ferric iron (Fe3+). The mean Hb at baseline for this cohort was 10.5 g/dL, Hct was 36% and RBC count was 7.6 10 6/ µL. After treatment with apoHb-Hp complex for 6 weeks, Hb levels improved to 11.3 g/dL and Hct to 38% vs. Hb of 10.1 g/dL and Hct of 35% for vehicle treated animals. The mean total RBC count at was 9.2 10 6/ µL following treatment with apoHb-Hp, and 7.7 10 6/ µL for vehicle treated animals at 6 weeks. Iron parameters were also improved, with lower mean serum iron levels in the apoHb-Hp treated group at 6 weeks when compared to vehicle control (90.5 µg/dL vs. 135.2 µg/dL, p < 0.05). Serum transferrin levels were 131.1 mg/dL vs. 90.3 mg/dL (p<0.05) for the apoHb-Hp and vehicle treated groups at 6 weeks respectively. Furthermore, when compared to control mice, apoHb-Hp mice had a significant reduction in both liver and spleen weights at 6 weeks- liver 5.7g vs. 5.2g (p<0.05) and spleen 3.8g vs. 3.4g (p<0.05) respectively. Finally, liver function tests also showed improvement following treatment with apoHb-Hp at 6 weeks, ALT 71.1 units/L vs. 85.5 units/L for the vehicle, AST levels 180.2 units/L vs. 217.6 for the vehicle (p <0.05) of, and ALP levels 247.3 units/L vs. 304.4 units/L (p <0.05). Our study demonstrates that apoHb-Hp can improve anemia and reduce iron toxicity in TI mice as well as improve liver and spleen parameters. Thus, apoHb-Hp may be a potential treatment strategy in this disease and merits further study. Figure 1 Figure 1. Disclosures Gopal: Alexion: Speakers Bureau; GBT: Consultancy; Pharming: Consultancy; Rigel Pharmaceuticals: Other: Clinical Trial, Research Funding.
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Tang, Wei, Xiaobin Zhang, Chuankui Yu, Linlang Wu, Han Zhang e Chenglin Li. "Microstructural Evolution and Deformation Behavior of a Solution-Treated Ti-Al-Mo-Fe Metastable Beta Titanium Alloy during Room-Temperature Deformation". Crystals 13, n.º 5 (15 de maio de 2023): 818. http://dx.doi.org/10.3390/cryst13050818.
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Beta titanium (β-Ti) alloys have been widely used in aerospace and biomedical implants due to their specific strengths, low elastic modulus, and their resistance to corrosion. As β titanium alloy is a novel metastable, Ti-2Al-9.2Mo-2Fe (wt.%) alloy is essential to understand microstructural evolution and deformation behavior at room temperature to improve the strength–ductility balance. The deformation behavior and microstructural evolution of the Ti-2Al-9.2Mo-2Fe alloy during room-temperature deformation has been investigated via electron backscatter diffraction (EBSD) and electron channeling contrast imaging (ECCI). It was found that the β-solution-treated alloy exhibited a single β phase with a lower β stability. However, the α/β-solution-treated alloy exhibited a layered structure, consisting of fine α + β grain layers and coarse β grain layers, and the β in the coarse grain layer had a lower stability, but the β in the fine grain layer had a higher stability owing to the coexistence of α. The β-solution-treated alloy was mainly deformed via {332}<113> deformation twinning, thus showing very high ductility; uniform elongation of approximately 35%. The α/β-solution-treated alloy was deformed via two mechanisms, namely {332}<113> deformation twinning in the coarse grain layers and dislocation slip in the fine grain layers. The α/β-solution-treated alloy exhibited high strength with a lower ductility due to the small amount of deformation twinning.
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Yang, Nana, Qing Li, Xinyue Zhang, Jingjing Xu, Shengyong Xu e Fengyu Liu. "From Transparent Cranial Windows to Multifunctional Smart Cranial Platforms". Electronics 11, n.º 16 (16 de agosto de 2022): 2559. http://dx.doi.org/10.3390/electronics11162559.
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In this paper, we briefly reviewed the development of cranial windows and their functions in brain sciences. We demonstrated that a 3D-printed titanium frame coated with a polydimethylsiloxane (PDMS) film could serve as an excellent transparent cranial window for long-period, in vivo optical experiments in mice and rats, and the devices also allowed multiple injections through the elastic PDMS window, without leaking. Our large-area honeycomb structured Ti-PDMS samples had a relative transparent area ratio of over 90% but a mechanical strength close to that of a human skull, showing a promising potential for applications in large animals as multifunctional cranial windows. We also suggested that more functional modules could be integrated in the large-area Ti-PDMS cranial device, thus turning it into a novel wearable smart platform for wireless data communication, electro-probing and brain stimulation, optical imaging, transcranial injection, and so on, for both fundamental research on neuroscience and clinical practices dealing with brain damage and disease.
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Potvin, Pierre G., e Benjamin G. Fieldhouse. "An NMR study of mixed, tartrate-containing TiIV complexes". Canadian Journal of Chemistry 73, n.º 3 (1 de março de 1995): 401–13. http://dx.doi.org/10.1139/v95-053.
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The reactions of amines and amino alcohols with diisopropyl or diethyl R,R- or S,S-tartrate and Ti(OiPr)4 were examined by 1H and 13C NMR to obtain and characterize nonfluxional complexes with the tartrate units in novel binding modes. The mildly acidic 8-hydroxyquinoline and N-phenyl-N-benzoylhydroxylamine selectively formed the products of a double OiPr substitution, Ti2(tartrate)2(ligand)2(OiPr)2, and the products of double tartrate substitution, Ti(ligand)2(OiPr)2, while 2,4-pentanedione formed only the latter Basic amino alkanols formed diastereomerically pure Ti2(tartrate)2(aminoalkoxide)(OiPr)3 species. N,N-Dimethyl-2-aminoethanol (Hdmae) also and uniquely formed monomeric Ti(tartrate)2(Hdmae)2 species that could be described as doubly zwitterionic. Secondary or tertiary amines formed triply C2-symmetric Ti3(tartrate)4(amine)2(OiPr)4 assemblies. Some minor components were believed to be μ-OiPr species. All mixed complexes except Ti(tartrate)2(Hdmae)2 contained chelating and bridging tartrate units, without coordination by ester carbonyls. A nonchelating, nonbridging tartrate unit was also present in the amino alcohol cases. Primary amines, aromatic amines, and hydrazines all failed to provide identifiable complexes. As well, N,N-dibenzylhydroxylamine failed to generate in solution the complex that had previously been characterized by X-ray crystallography. Amidst the rich chemistry of TiIV-tartrate systems, the evident selectivities in product formation were ascribed to macro-ring closures that are specifically directed by the electronic nature of the addend. Transient OiPr-bridged intermediates were also implicated. Keywords: mixed TiIV alkoxides, chiral TiIV alkoxides, enantiospecific complexation.
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Hosoe, Naoki, Kazuo Ohtsuka, Yutaka Endo, Makoto Naganuma, Noriyuki Ogata, Yuichiro Kuroki, Seiko Sasanuma et al. "Insertability comparison of passive bending single-balloon prototype versus standard single-balloon enteroscopy: a multicenter randomized non-blinded trial". Endoscopy International Open 06, n.º 10 (outubro de 2018): E1184—E1189. http://dx.doi.org/10.1055/a-0650-4168.
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Abstract Background and study aims Traversing the ileocecal valve (ICV) is technically challenging with a retrograde approach to single-balloon enteroscopy (SBE). A novel technique called responsive insertion technology (RIT) colonoscopy was developed to obtain a higher cecal intubation rate in this setting. A prototype long SBE equipped with RIT (P-SBE) was developed to obtain superior insertability. The aim of this study was to compare the insertability of a standard single-balloon enteroscope (S-SBE) versus a P-SBE. Patients and methods This study was a multicenter, randomized, non-blinded, trial of 62 patients with small bowel pathologies. All procedures were performed with SBE via the trans-anal route. Procedure success was defined as stable intubation of the terminal ileum (TI) 20 cm beyond the ICV. The primary variable was time to reach stable TI intubation 20 cm beyond the ICV (TSTII). If stable TI intubation was not achieved within 10 minutes, the initial SBE was removed through the indwelling overtube and replaced with another SBE. Results Sixty patients were examined with two patients excluded from this study. TSTII using P-SBE was significantly decreased compared to S-SBE (mean P-SBE vs S-SBE: 98.3 vs 169.4 second, P = 0.006). The completion rates for stable intubation within 10 minutes of using P-SBE and S-SBE were 96.8 % and 86.2 %, respectively (P = 0.19). On endoscope replacement, all patients had achieved stable TI intubation. Conclusions SBE with RIT improves insertability when traversing the ileocecal valve in retrograde SBE.
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Păun, Angela Gabriela, Cristina Dumitriu, Camelia Ungureanu e Simona Popescu. "Silk Fibroin/ZnO Coated TiO2 Nanotubes for Improved Antimicrobial Effect of Ti Dental Implants". Materials 16, n.º 17 (26 de agosto de 2023): 5855. http://dx.doi.org/10.3390/ma16175855.
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The aim of the present research is to develop a novel hybrid coating for a Ti dental implant that combines nature-inspired biomimetic polymers and TiO2 nanostructures with an entrapped ZnO antimicrobial agent. ZnO was used in other studies to cover the surface of Ti or Ti–Zr to reduce the need of clinical antibiotics, prevent the onset of peri-implantitis, and increase the success rate of oral clinical implantation. We developed an original coating that represents a promising approach in clinical dentistry. The titanium surface was first anodized to obtain TiO2 nanotubes (NT). Subsequently, on the NT surface, silk fibroin isolated from Bombyx mori cocoons was deposited as nanofibers using the electrospun technique. For an improved antibacterial effect, ZnO nanoparticles were incorporated in this biopolymer using three different methods. The surface properties of the newly created coatings were assessed to establish how they are influenced by the most important features: morphology, wettability, topography. The evaluation of stability by electrochemical methods in simulated physiological solutions was discussed more in detail, considering that it could bring necessary information related to the behavior of the implant material. All samples had improved roughness and hydrophilicity, as well as corrosion stability (with protection efficiency over 80%). The antibacterial test shows that the functional hybrid coating has good antibacterial activity because it can inhibit the proliferation of Staphylococcus aureus up to 53% and Enterococcus faecalis up to 55%. All Ti samples with the modified surface have proven superior properties compared with unmodified TiNT, which proved that they have the potential to be used as implant material in dentistry.
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Xu, Lang, e Zhongwei Huang. "Effect of Surface Nanomodification of Titanium Implants on Adhesion, Bone Bonding, and Bacterial Aggregation of Gingival Epithelial Cells and Fibroblasts". Science of Advanced Materials 15, n.º 8 (1 de agosto de 2023): 1072–81. http://dx.doi.org/10.1166/sam.2023.4508.
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Implant-supported dentures have become a major approach to edentulous/defective repair. Peri-implantitis is a major factor leading to implant failure. The emergence of antibacterial peptides has provided a novel idea for the study of antibacterial coatings on implant surfaces. The antibacterial peptide GL13K was modified onto the surface of titanium (Ti) by silanization with 3-chloropropyltriethoxysilane, and its physicochemical properties were characterized. After its coculture with Porphyromonas gingivalis (P. g) in vitro, the cell activity was detected, and the antibacterial properties were analyzed. After its coculture with gingival fibroblasts (GFs) in vitro, CCK-8 was adopted to detect cell proliferation and analyze cytotoxicity. After its coculture with gingival epithelial cells (GECs) and GFs in vitro, the adhesion was demonstrated by acridine orange staining and DAPI staining. The smooth Ti implant (S/T), the microgroove Ti implant (E/T), and the GL13K-modified microgroove Ti implant (GL13K/E/T) were implanted into the inferolateral aspect of the femoral condyle of the right posterior limb of healthy New Zealand rabbits. Four weeks after surgery, the levels of osteoprotegerin (OPG) and nuclear factor-kappa B ligand (RANKL) in the bone tissue around the implant were detected by immunohistochemistry. The results revealed that relative to the S/T and E/T materials, the surface roughness and contact angle of the GL13K/E/T material were enhanced, while the metabolic activity and colony count of P. g were decreased. S/T, E/T, and GL13K/E/T materials had no notable effect on the viability of GFs (P > 0.05). Relative to the S/T material, the numbers of GECs and GFs attached to the surfaces of the E/T and GL13K/E/T materials were drastically increased (P < 0.05). Furthermore, relative to the S/T group, OPG levels in the peri-implant bone tissues of the E/T and GL13K/E/T groups were increased, while the RANKL level was decreased (P < 0.05). In contrast to group E/T, OPG in the peri-implant bone tissue of rabbits of the GL13K/E/T group was increased, while the RANKL was decreased (P < 0.05). In summary, the Ti implant with a microgroove structure modified by the antibacterial peptide GL13K had an ideal antibacterial effect and promoted the adhesion and growth of GECs and GFs. In addition, the antibacterial peptide GL13K-modified Ti implant with a microgroove structure could promote early bone bonding.
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SUZUKI, YOSHIKAZU, MARIE-HÉLÈNE BERGER, DANIELA D'ELIA, PIERRE ILBIZIAN, CHRISTIAN BEAUGER, ARNAUD RIGACCI, JEAN-FRANÇOIS HOCHEPIED e PATRICK ACHARD. "SYNTHESIS AND MICROSTRUCTURE OF A NOVEL TiO2 AEROGEL–TiO2 NANOWIRE COMPOSITE". Nano 03, n.º 05 (outubro de 2008): 373–79. http://dx.doi.org/10.1142/s1793292008001222.
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TiO 2 aerogel–10 mol% TiO 2 nanowire composite was prepared by a sol–gel technique with the addition of TiO 2 nanowires to TiO 2 sol, followed by supercritical drying in CO 2. TiO 2 nanowires (anatase with minor rutile phases) as dispersoid were prepared by a hydrothermal process followed by calcination in air at 600°C. The TiO 2 nanowires were dispersed in a 2-propanol/ H 2 O / HNO 3 solution, and the mixture was added drop by drop to a tetrabutyl orthotitanate [i.e. Ti (IV) n-butoxide] solution in 2-propanol. After gelation, the TiO 2 alcogel– TiO 2 nanowire composite was dried in supercritical CO 2 to obtain the final, TiO 2 aerogel– TiO 2 nanowire composite. TEM analysis revealed that a unique "nanowire network" structure was formed within the mesoporous aerogel matrix. The aerogel– TiO 2 nanowire composite had a relatively large surface area 427 m2/g, with mesopores ~ 16 nm in diameter and a pore of volume of 1.63 cm3/g.
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Cui, Tao, Hong Wei Zhao, Chuang Liu e Ye Tian. "Microstructure Evolution of Ti-6Al-4V Alloy during High Speed Cutting: An Investigation Using Finite Element Simulation". Applied Mechanics and Materials 421 (setembro de 2013): 193–200. http://dx.doi.org/10.4028/www.scientific.net/amm.421.193.
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In this paper, a novel model combining the microstructure prediction model and a modified constitutive model of the Johnson-Cook (JC) model was developed and embedded into FEM software via the user subroutine. The chip formation and microstructure evolution in high speed cutting of Ti-6Al-4V alloy were simulated based on the presented model. The results indicated that dynamic recrystallization mainly happened in ASBs, where the grain size had a big decline. According to the variation of cutting temperature and grain size of microstructure, the mechanism of the adiabatic shear bands (ASBs) formation was investigated deeply and concluded that dynamic recrystallization was the root cause of the serrated chip formation.
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Hegelund, L., e JT Sørensen. "Measuring fearfulness of hens in commercial organic egg production". Animal Welfare 16, n.º 2 (maio de 2007): 169–71. http://dx.doi.org/10.1017/s0962728600031250.
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AbstractTo evaluate agreement between flock-based fear tests used in welfare assessments of laying hens in commercial organic farms, three tests were applied in 27 flocks of layers. Tests were performed at 35 and 55 weeks of age and were based on the concepts of ‘novel object’, ‘sudden sound’ and two different measures of ‘approaching human’. In general, agreements between tests were poor. The two measures based on ‘approaching human’ had the highest agreement, while the agreement between all other flock-based tests were lower. There was low agreement between testing at age 35 and 55 weeks.In order to evaluate the degree to which the flock-based fear tests reflect individual hens' underlying fearfulness; tonic immobility (TI) tests were also applied on individual hens in eight flocks. There was large individual variation in the duration of tonic immobility, but also significant difference between flocks regarding mean duration of immobilisation. However there was no statistically significant association between TI-tests and flock-based tests. These results emphasise the need for careful consideration of choice of test stimuli for flock-based fear tests, and indicate that the investigated flock-based fear tests do not reflect the individual hens' underlying fearfulness.
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Napol’skikh, Julia, Andrei Shoppert, Irina Loginova, Sergey Kirillov e Dmitry Valeev. "Selective Recovery of Scandium (Sc) from Sulfate Solution of Bauxite Residue Leaching Using Puromet МТS9580 Ion-Exchange Sorption". Metals 14, n.º 2 (15 de fevereiro de 2024): 234. http://dx.doi.org/10.3390/met14020234.
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Rare earth elements (REEs) and Sc are concentrated in aluminum production byproducts. The novel REEs recovery approach, which involves leaching with acid at a pH > 3 in the presence of MgSO4, results in the formation of a pregnant leach solution (PLS) with a low concentration of iron (Fe) and titanium (Ti) and a large number of valuable elements. This work studies the application of chelating resin Puromet МТS9580 in the sorption recovery of Sc from sulfate solutions. To analyze the static Sc sorption data, Langmuir, Freundlich, and Temkin isotherm models were used. The Langmuir isotherm model was the best fitted to the experimental data, with a coefficient of determination (R2) of 0.983. The dynamic adsorption experiment was conducted using a PLS and a simulated solution without contaminants. Adsorption of Sc from the simulated solution was better fitted to the Thomas model with a Sc capacity greater than 6.4 mg mL−1. Because Ti had a gradual decrease in C/C0, which the Thomas model was unable to simulate, the modified dose-response (MDR) model fitted better with PLS with a Sc capacity greater than 3.8 mg mL−1. The NaHCO3 solution (200 g L−1) effectively desorbed Sc (>98%) from simulated and PLS solutions after 1.5 h of stirring in a batch mode. After 1.5 h of desorption, the concentration of Sc in the desorption solution was 461.5 mg L−1, while the concentration of Mg and Ti was lower than 200 mg L−1 and 50 mg L−1, respectively.
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Bally, Cecile, Raphael Itzykson, Berangere Gruson, Dreyfus Francois, Virginie Siguret, Anne-Laure Taksin, Benoit de Renzis et al. "Azacitidine (AZA) After Failure of Lenalidomide (LEN) in Low/Int-1 Risk MDS with Del 5q". Blood 118, n.º 21 (18 de novembro de 2011): 2786. http://dx.doi.org/10.1182/blood.v118.21.2786.2786.
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Abstract Abstract 2786 Background: LEN is currently the reference treatment of low/int 1 (lower) risk MDS with del 5q, yielding RBC transfusion independence (TI) in two thirds of the cases, with a median RBC-TI duration of 2.2 years. (MDS 003 trial, List, NEJM, 2006). In case of primary or secondary failure of LEN, however combined analysis of MDS 003 and MDS 004 trial showed prognosis to be unfavorable and treatment approaches uncertain. We report results of treatment with AZA in 13 lower risk MDS with del 5q with primary or secondary failure of LEN. Methods: The 13 cases were treated between November 2005 and June 2011 in 10 centers of the Groupe Francophone des Myelodysplasies (GFM). At onset of LEN, median age was 71 years, M/F 0.43, 7 patients (pts) had RAEB 1 and 6 RA, 11 had isolated del 5q and 2 had 1 additional chromosomal abnormality. IPSS was low in 6 and int 1 in 7 patients. The LEN dose was 5mg/d, 10mg/d 3 weeks/4weeks, 10mg/d in 8, 3 and 2 patients, respectively. 11 (85%) patients had achieved RBC-TI, for a median duration of 26.3m (range 5.8–57.3)(secondary failures), while 2 patients had not achieved RBC-TI (primary failures). At onset of AZA, 11 patients had progressed with a change in WHO category (RA to RAEB1, or RAEB 1 to RAEB2) in 8 patients, and/or acquisition of additional chromosomal abnormalities in 9 patients, 5 eventually having complex karyotype, of whom 2 had chromosome 17 abnormality leading to TP53 gene deletion (TP53 mutation analysis is in progress); IPSS was low (n=0), int 1 (n= 3), int 2 (n=2), high (n=8). Prior to onset of AZA, attempts had been made to increase the LEN dose from 5 to 10 mg/d in 2 patients, without success. Results: AZA was administered at the FDA/EMEA approved schedule (75mg/m2/dx7) in 12 pts, and reduced (5 day schedule) in 1 pt. The median number of cycles administered was 6 (range 1–23). Five patients (46%) achieved a response according to IWG 2006 criteria, including CR, PR, HI in 1, 0 and 4 pts respectively. All 5 responders achieved RBC –TI. 4 patients received less than 4 cycles of AZA: 2 stopped AZA after 1 cycle for hematological toxicity, 1 stopped after 3 cycles for progression, 1 pt died from septic shock after 3 cycles. Response duration was 2.9+, 4.4+, 6.2+, 13.8, and 24.6 months, respectively. No responder was allografted, but the age of responders was 68, 70, 78, 78 and 86 years, respectively. Median survival from onset of AZA was 8.8 m (range 0.8–24.9). The 5 responders were still alive 3+, 4.4+, 6.2+, 13.9+ and 24.8+ m after onset of AZA, while median survival in non-responders was 8.7 months. Among the 5 patients who responded to AZA, 4 had at onset of AZA a high IPSS, 3 had complex karyotype and 2 one additional chromosomal abn, while 4/5 had previously achieved RBC-TI with LEN (with a median duration of 26.1 months). Neither of the 2 patients with TP53 deletion responded to AZA. Finally, among the 2 primary failures to Lenalidomide, one achieved HI with AZA (of 4.4+ months duration) and the other died within 2 months. Conclusion: In this relatively small series almost 40% of the patients with lower risk MDS and del 5q who progressed under LEN could be salvaged by AZA, and might expect survival prolongation. The appearance of novel chromosomal abnormalities or complex karyotype at progression did not predict poor response to AZA, while we are currently analyzing the prognostic value of TP 53 mutations, which occur frequently at th at disease stage (Jadersten, JCO 2011), on response to AZA. Disclosures: Fenaux: Celgene: Honoraria, Research Funding.
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Mittelman, Moshe, David H. Henry, John Glaspy, Anil Tombak, Rosemary Anne Harrup, Krzysztof Madry, Barbara Grabowska, Uwe Platzbecker, Tyson Lee e Katharina Modelska. "Efficacy and Safety of Roxadustat for Treatment of Anemia in Patients with Lower-Risk Myelodysplastic Syndrome (LR-MDS) with Low Red Blood Cell (RBC) Transfusion Burden: Results of Phase III Matterhorn Study". Blood 142, Supplement 1 (28 de novembro de 2023): 195. http://dx.doi.org/10.1182/blood-2023-180749.
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Presented on behalf of all MATTERHORN (FGCL-4592-082) study investigators Introduction: For patients (pts) with LR-MDS, anemia poses a major clinical challenge, with limited response to first-line erythropoietin (EPO)-stimulating agents (ESAs) and a median duration of response ≤2 years. Further, pts with RBC transfusion dependence (≥2 packed RBC [pRBC] units every 8 weeks [Q8W]) are less likely to respond to ESAs. Anemia treatments with novel mechanisms of action enabling transfusion independence (TI) are needed to reduce frequent RBC transfusion burden. Roxadustat is a first-in-class, hypoxia-inducible factor prolyl hydroxylase inhibitor for treatment of anemia with chronic kidney disease. In the MATTERHORN (NCT03263091) dose-selection stage, roxadustat was well-tolerated, and 37.5% of pts (9/24) with LR-MDS and low RBC transfusion burden ([LTB] 1 pRBC unit Q8W for two consecutive 8-week periods or 2-4 pRBC units Q8W) achieved TI. In the MATTERHORN double-blind stage, TI response rate and safety of roxadustat were further assessed. Methods: MATTERHORN is an ongoing, double-blind, Phase III, randomized, placebo (PBO)-controlled trial. Eligible adult pts (≥18 years of age) had very low-, low-, or intermediate-risk primary MDS per Revised International Prognostic Scoring System (IPSS-R) classification (<5% bone marrow blasts); hemoglobin (Hb) ≤10.0 g/dL at baseline (BL); and LTB. Prior ESA use (>8 weeks before randomization) was permitted. Pts were randomized 3:2 to roxadustat or PBO, then stratified by serum EPO concentration (≤200 or 200-400 mIU/mL), IPSS-R risk, and transfusion burden. Pts received oral roxadustat (starting dosage: 2.5 mg/kg three times weekly based on the dose-selection stage) or PBO with best supportive care (BSC; per institutional criteria, including RBC transfusion) for a 52-week treatment period, followed by a 4-week follow-up period. Primary efficacy endpoint was percentage of pts with TI (the absence of RBC transfusion) for ≥56 consecutive days during the first 28 treatment weeks (TI responder). The percentage of pts with TI and mean Hb increase of ≥1.0 and ≥1.5 g/dL (averaged over 8 weeks) compared with BL pretransfusion Hb was also assessed (to be reported separately). Safety (including treatment-emergent adverse events [TEAEs] and serious TEAEs) was evaluated throughout the study. Results: As of the final 28-week interim analysis of the double-blind stage (data cutoff: April 24, 2023), 140 pts (82 roxadustat, 58 PBO) were randomized and treated. Across arms, median age was 71.5 years (range, 26-96), 59.3% (83/140) were male, and 80.0% (112/140) were white. Most pts (72.1% [101/140]) had IPSS-R low-risk disease and a transfusion burden of 2-4 pRBC units Q8W (92.1% [129/140]). Median (range) BL transfusion burden was 2.5 (1-10) pRBC units. Seventy pts (50.0%) received prior ESAs (98.6% [69/70] were ESA-refractory). Eighty-four pts (41/82 [50.0%] roxadustat, 43/58 [74.1%] PBO) completed 28 weeks of treatment, and 15 pts (6/82 [7.3%] roxadustat, 9/58 [15.5%] PBO) were continuing treatment. Median (range) treatment duration was 24.1 (1.1-28.0) weeks for the roxadustat arm and 28.0 (0.1-28.0) weeks for the PBO arm. A greater percentage of pts in the roxadustat arm compared with the PBO arm were TI responders (47.5% vs. 33.3%). However, this difference did not reach statistical significance ( p=0.22; figure). Percentages of pts with TEAEs of any grade, serious TEAEs, and TEAEs leading to treatment discontinuation were similar across arms (table). Six deaths occurred on study (roxadustat: pneumonia [n=2], acute myocardial infarction and ischemic stroke [n=1], multiorgan failure [n=1]; PBO: urosepsis [n=1], disease progression [n=1]). Three pts (all in roxadustat arm) progressed to acute myeloid leukemia. The study was terminated by the sponsor and is currently being completed. Conclusions: Despite not meeting the primary endpoint, roxadustat plus BSC was well-tolerated, and a high percentage of pts with LR-MDS and LTB were TI responders. The high TI response rate in the PBO arm, historically poor outcomes in pts with ESA-refractory disease, and the inclusion of pts who were not transfusion-dependent (1 pRBC unit Q8W) may have contributed to the lack of a statistically significant difference in TI response rates between arms. MATTERHORN outcomes highlight the continued unmet need for effective and safe therapies that reduce RBC transfusion burden in LR-MDS.
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Cui, Ning, Qianqian Wu, Kexiao Bi, Tiewei Xu e Fantao Kong. "Effect of Heat Treatment on Microstructures and Mechanical Properties of a Novel β-Solidifying TiAl Alloy". Materials 12, n.º 10 (23 de maio de 2019): 1672. http://dx.doi.org/10.3390/ma12101672.
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The effect of heat treatment on the microstructures and mechanical properties of a novel β-solidifying Ti–43Al–2Cr–2Mn–0.2Y alloy was investigated. A fully lamellar (FL) microstructure with a colony size of about 100 μm was obtained by heat treatment at 1320 °C/10 min/furnace cooling (FC). A duplex (DP) microstructure with globular γ grains and γ/α2 lamellae was obtained by heat treatment at 1250 °C/4 h/FC. The residual hard–brittle β0 phase was also eliminated after heat treatment. The mechanical properties of the β-solidifying TiAl alloy depended closely on the heat treatment. The FL alloy had better fracture toughness, and the fracture toughness (KIC) value was 24.15 MPa·m1/2. The DP alloy exhibited better ductility, and the room temperature (RT) elongation of the alloy could reach 1%. The elongation of the alloy with different microstructures sharply increased when the temperature increased from 700 to 750 °C, indicating that the microstructure had no effect on the ductile–brittle transition temperature of the β-solidifying TiAl alloy. The fracture morphologies of different tensile specimens were observed. Interlamellar and translamellar fractures were the main fracture features of the FL alloy. Intergranular, translamellar, and interlamellar fractures were the main fracture features of the DP alloy.