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Zirconia ceramics exhibit a martensitic phase transformation that enables large strains of order 10%, making them prospects for shape-memory and superelastic applications at high temperature1-5. Similarly to other martensitic materials, this transformation strain can be engineered by carefully alloying to produce a more commensurate transformation with reduced hysteresis (difference in transformation temperature on heating and cooling)6-11. However, such 'lattice engineering' in zirconia is complicated by additional physical constraints: there is a secondary need to manage a large transformation volume change12, and to achieve transformation temperatures high enough to avoid kinetic barriers6. Here we present a method of augmenting the lattice engineering approach to martensite design to address these additional constraints, incorporating modern computational thermodynamics and data science tools to span complex multicomponent spaces for which no data yet exist. The result is a new zirconia composition with record low hysteresis of 15 K, which is about ten times less transformation hysteresis compared to typical values (and approximately five times less than the best values reported so far). This finding demonstrates that zirconia ceramics can exhibit hysteresis values of the order of those of widely deployed shape-memory alloys, paving the way for their use as viable high-temperature shape-memory materials.
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OBJECTIVES: To systematically review long-term (> 5 years) outcomes of ESP surgery for OSA treatment over 17 years. METHODS: Systemic review of MEDLINE, Google Scholar, Cochrane Library and Evidence Based Medicine Reviews to identify publications relevant to OSA and Expansion Pharyngoplasty and its variants. All relevant studies published between January 2007 and June 2023 were included. RESULTS: Twelve studies were included in this systematic review with a combined total of 1373 patients who had the ESP procedure were included. The clinical outcomes included encouraging long-term success rate, reductions in Epworth sleepiness scale, good mean disease alleviation, anatomical structural area and volume improvements, blood pressure reductions, biochemical improvements in acute phase reactants after ESP surgery, reductions in intra-ocular pressures, and post-operative reduction of sympathetic overdrive. CONCLUSIONS: Seventeen years on, the expansion sphincter pharyngoplasty has demonstrated not only increase in anatomical area and volume but significant desired improvements in polysomnographic, clinical and biochemical parameters post-surgery.
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Faringe , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/cirurgia , Faringe/cirurgia , Resultado do Tratamento , Procedimentos Cirúrgicos Otorrinolaringológicos/métodosRESUMO
Grain refinement is a widely sought-after feature of many metal production processes and frequently involves a process of recrystallization. Some processing methods use very high strain rates and high strains to refine the grain structure into the nanocrystalline regime. However, grain refinement processes are not clear in these extreme conditions, which are hard to study systematically. Here, we access those extreme conditions of strain and strain rate using single copper microparticle impact events with a laser-induced particle impact tester. Using a combined dictionary-indexing electron backscatter diffraction and scanning transmission electron microscopy approach for postmortem characterization of impact sites, we systematically explore increasing strain levels and observe a recrystallization process that is facilitated by nanotwinning, which we term nanotwinning-assisted dynamic recrystallization. It achieves much finer grain sizes than established modes of recrystallization and therefore provides a pathway to the finest nanocrystalline grain sizes through extreme straining processes.
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Alumínio , Cobre , Alumínio/química , CristalizaçãoRESUMO
OBJECTIVE: A 15 year review of the outcomes and success rates of the Expansion Sphincter Pharyngoplasty (ESP) in the treatment of patients with obstructive sleep apnea (OSA). METHODS: A systemic review with two independent searches of MEDLINE, Google Scholar, Cochrane Library and Evidence-Based Medicine Reviews to identify publications relevant to OSA and Expansion Pharyngoplasty. All relevant studies published before 31 December 2021 were included. RESULTS: Sixteen studies were included in this strict systematic review with a total of 747 patients who had the ESP procedure were included. The mean age was 41.3 years, mean BMI 28.2, the mean pre-op AHI was 32.3 and post-op AHI was 10.0 (p < 0.05), the mean pre-op ESS was 11.4, had reduced to post-op 5.3 (p < 0.05), and the mean pre-op snore VAS decreased from 8.7 to 2.9 (p < 0.05), with a mean follow-up time of 9.5 months. The overall pooled success rate for all the 747 patients was 80.0%. There were no significant reported complications noted in these studies. CONCLUSION: After 15 years of presence, the expansion sphincter pharyngoplasty has shown to be reliably effective in the management of patients with OSA.
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Faringe , Apneia Obstrutiva do Sono , Adulto , Humanos , Faringe/cirurgia , Ronco , Resultado do TratamentoRESUMO
OBJECTIVES: Systematic review of palate surgery for the treatment of OSA. METHODS: Independent searches to identify publications relevant to OSA treatment and upper airway palate surgery. All relevant studies published between January 2001 and February 2018 were included. Inclusion criteria were adult patients, documented airway evaluation methods and absent hypopharyngeal collapse. Outcomes included success rates of treatment, AHI, Epworth scale, QOL and snoring VAS. RESULTS: Fifty-nine papers with a total of 2715 patients, UPPP accounted for 16.7% of all the procedures. Evident differentiation progressing from 2001 to 2018, from 2001 to 2010, the percentage of UPPP procedures were 25.67%, from 2011 to 2018, there were only 12.6% of UPPP procedures. The average follow up was 8.18 months. Meta-analysis on the AHI change for all procedures, showed the fixed effect AHI per follow-up (FU) month change was 1.45 (95% CI 1.33, 1.8), p < 0.001; while for ESS, the fixed effect AHI per FU month change was 0.61 (95% CI 0.56, 0.66), p < 0.001. The mean decrease in AHI was from 35.66 to 13.91 (p < 0.001). The mean decrease in ESS was from 11.65 to 5.08 (p < 0.001). The mean AHI change was 19.9 (p < 0.001). The mean ESS change was 5.8 (p < 0.001). The overall pooled success rate was 67.5%. Meta-analysis of the procedures, showed that the respective mean AHI reduction was 24.7 for the anterior palatoplasty (p = 0.015), 19.8 for the lateral/expansion pharyngoplasty (p = 0.046), and 17.2 for the uvulopalatopharyngoplasty (p = 0.360). CONCLUSIONS: Better understanding of the upper airway and objective airway evaluation diagnostic techniques and innovative palate surgeries have improved success rates of OSA surgery.
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Palato/cirurgia , Apneia Obstrutiva do Sono/cirurgia , Adulto , Humanos , Faringe/cirurgia , Fatores de TempoRESUMO
This study seeks to determine the success rates of the expansion sphincter pharyngoplasty and its variants on the treatment of obstructive sleep apnea (OSA). Systematic review and meta-analysis. Two independent searches of MEDLINE, Google Scholar, Cochrane Library and Evidence Based Medicine Reviews to identify publications relevant to OSA and expansion pharyngoplasty. All relevant studies published before 31 March 2015 were included. Five studies were included in the systematic review and meta-analysis. The numbers of patients in each paper ranged from 10 to 85 (total = 155), and mean age ranged from 8 to 56 years. Substantial and consistent improvement in PSG outcomes were observed post-expansion pharyngoplasty patients, with or without multilevel surgery groups. The results showed that the expansion pharyngoplasty technique has significantly lower AHI than control group [Standardised mean difference -7.32, 95 %CI (-11.11, -3.52), p = 0.0002]; however, substantial heterogeneity between these studies were observed. The mean pre-operative AHI (in the five papers) improved from 40.0 ± 12.6 to 8.3 ± 5.2 post-operatively. The overall pro-rated pooled success rate for all the patients was 86.3 %. The expansion pharyngoplasty is effective in the management of patients with OSA.
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Faringe/cirurgia , Apneia Obstrutiva do Sono/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Humanos , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/fisiopatologia , Adulto JovemRESUMO
Accurate pattern center determination has long been a challenge for the electron backscatter diffraction (EBSD) community and is becoming critically accuracy-limiting for more recent advanced EBSD techniques. Here, we study the parameter landscape over which a pattern center must be fitted in quantitative detail and reveal that it is both "sloppy" and noisy, which limits the accuracy to which pattern centers can be determined. To locate the global optimum in this challenging landscape, we propose a combination of two approaches: the use of a global search algorithm and averaging the results from multiple patterns. We demonstrate the ability to accurately determine pattern centers of simulated patterns, inclusive of effects of binning and noise on the error of the fitted pattern center. We also demonstrate the ability of this method to accurately detect changes in pattern center in an experimental dataset with noisy and highly binned patterns. Source code for our pattern center fitting algorithm is available online.
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OBJECTIVE: Does nasal surgery affect multilevel surgical success outcome. METHODS: Prospective eight country nonrandomized trial of 735 obstructive sleep apnea (OSA) patients, who had multilevel palate and/or tongue surgery, divided into two groups, with or without nose surgery. RESULTS: There were 575 patients in nose group, 160 patients in no nose group. The mean age for nose group 44.6 ± 11.4, no nose group 44.2 ± 11.8. Mean preoperative BMI for nose group 27.5 ± 3.6, no nose group 27.5 ± 4.1, mean postoperative BMI nose group 26.3 ± 3.7, no nose group 27.1 ± 3.8 (P = .006). Mean preoperative AHI nose group 32.7 ± 19.4, no nose group 34.3 ± 25.0 (P = .377); and mean postoperative AHI nose group 13.5 ± 10.2, no nose group 17.1 ± 16.0 (P = .001). Mean preoperative ESS nose group was 11.3 ± 4.7, no nose group was 10.4 ± 5.4 (P = .051); and mean postoperative ESS nose group was 5.3 ± 3.2, no nose group was 6.7 ± 2.8 (P = .001). The nose group had higher percentage change (adjusted for age, gender, BMI) in AHI (33.7%, 95% CI 14% to 53.5%) compared to the no nose group (P = .001); the nose group also had more percentage change in ESS (37%, 95% CI 23.6% to 50.3%) compared to the no nose group (P < .001). Change in BMI did not affect AHI nor ESS change (Cohen effect 0.03 and 0.14, respectively). AHI change in both groups were also statistically significant in the mild OSA (P = .008) and the severe OSA (P = .01). Success rate of surgery for the nose group 68.2%, while the no nose group 55.0% (P = .002). CONCLUSION: Combining nose surgery in multilevel surgery improves surgical success. LEVEL OF EVIDENCE: IIC.
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OBJECTIVES/HYPOTHESIS: To investigate long-term complications of newer reconstructive palate surgery techniques. STUDY DESIGN: Retrospective case-series analysis. METHODS: Retrospective six-country clinical study of OSA patients who had nose and palate surgery. RESULTS: There were 217 patients, mean age = 43.9 ± 12.5 years, mean body mass index = 25.9 ± 4.7, mean preoperative apnea-hypopnea index [AHI] = 30.5 ± 19.1, follow-up 41.3 months. A total of 217 palatal procedures were performed, including 50 expansion sphincter pharyngoplasties (ESP), 34 functional expansion pharyngoplasties (FEP), 40 barbed reposition pharyngoplasties (BRP), 64 modified uvulopalatopharyngoplasties (mUPPP), 11 uvulopalatal flap procedures (UPF), nine suspension pharyngoplasties (SP), eight relocation pharyngoplasties (RP), and one z-pharyngoplasty (ZPP). Complications included were constant and/or felt twice per week; dry throat (7.8%), throat lump feeling (11.5%), throat phlegm (10.1%), throat scar feeling (3.7%), and difficulty swallowing (0.5%). Of the 17 patients who had a dry throat complaint, two were constant (one SP, one RP), 15 were occasional (10 mUPPP, three SP, two BRP). Of the 25 patients with the throat lump feeling, four were constant (three RP, one ZPP), 21 were occasional (10 mUPPP, five SP, five UPF, one BRP). Of the 22 patients with the throat phlegm feeling, four were constant (two SP, two RP), 18 were occasional (10 mUPPP, four BRP, two FEP, two SP). Of the eight patients with throat scar feeling, eight were occasional (four SP, two mUPPP, one FEP, one RP), none were constant. One patient had difficulty swallowing (RP procedure). There was no velopharyngeal incompetence, taste disturbance, nor voice change. Highest symptom complaints were mUPPP, SP, and RP, whereas the lowest symptom complaint was ESP. CONCLUSIONS: Newer palatal techniques have shown to have less long-term complications compared to the older ablative techniques. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2281-2284, 2020.
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Nariz/cirurgia , Palato/cirurgia , Procedimentos de Cirurgia Plástica/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Apneia Obstrutiva do Sono/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Faringite/epidemiologia , Faringite/etiologia , Complicações Pós-Operatórias/etiologia , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Insuficiência Velofaríngea/epidemiologia , Insuficiência Velofaríngea/etiologiaRESUMO
OBJECTIVES/HYPOTHESIS: Our objective was to determine whether drug-induced sleep apnea (DISE) affects the successfulness of the surgical outcome. STUDY DESIGN: Prospective, seven-country, nonrandomized trial. METHODS: There were 326 consecutive obstructive sleep apnea (OSA) patients who had nose, palate, and/or tongue surgery included in the study. DISE was performed in only one group. RESULTS: There were 170 patients in the DISE group and 156 patients in no-DISE group. The mean preoperative body mass index (BMI) for the DISE group was 27.6 ± 4.6, whereas in the no-DISE group it was 28.1 ± 3.9 (P = .23). The mean preoperative systolic blood pressure (SBP) for the DISE group was 130.4 ± 16.7, whereas in the no-DISE group it was 142.9 ± 15.5 (P < .001). The mean preoperative diastolic blood pressure (DBP) for the DISE group was 81.4 ± 9.7, whereas in the no-DISE group it was 89.1 ± 9.7 (P < .001). The mean preoperative apnea-hypopnea index (AHI) for the DISE group was 32.6 ± 18.8, whereas in the no-DISE group it was 33.7 ± 19.6 (P = .61). The mean postoperative AHI for the DISE group was 15.9 ± 12.6, whereas in the no-DISE group it was 13.2 ± 8.8 (P = .023). The age-, gender-, BMI-adjusted percentage change in AHI for the DISE group was -48.4 ± 31.9, whereas in the no-DISE group it was -59.8 ± 18.6 (P < .001). The age-, gender-, and BMI-adjusted success rate for the DISE group was 66.5%, whereas in the no-DISE group it was 80.8% (P = .004). The age-, gender-, and BMI-adjusted change in SBP for the DISE group was -6.1 ± 8.6, whereas in the no-DISE group it was -13.3 ± 11.1 (P < .001). The age-, gender-, and BMI-adjusted change in DBP in the DISE group was -5.2 ± 12.1, whereas in the no-DISE group it was -12.4 ± 11.7 (P < .001). The mean age- and gender-adjusted change in BMI for the DISE group was -4.6 ± 12.9, whereas in the no-DISE group it was -6.3 ± 18.5 (P = .34). The Cohen effect of BMI on the overall AHI, lowest oxygen saturation, and blood pressure changes was 0.08. CONCLUSIONS: DISE may not significantly affect surgical success in OSA. LEVEL OF EVIDENCE: 2c Laryngoscope, 130:551-555, 2020.
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Endoscopia/métodos , Hipnóticos e Sedativos/farmacologia , Apneia Obstrutiva do Sono/cirurgia , Sono/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
OBJECTIVES/HYPOTHESIS: To evaluate if upper airway surgery reduces blood pressure in patients with obstructive sleep apnea (OSA). STUDY DESIGN: Prospective series. METHODS: A prospective series of 112 consecutive OSA patients with hypertension (HTN). All patients were > 18 years old, respiratory disturbance index >5, all levels of apnea-hypopnea index (AHI), with a history of HTN treated with medication for at least 6 months. Surgical procedures included septoplasty, turbinate reduction, palate surgery, and tongue base reduction. RESULTS: There were 92 men and 20 women, with a mean age of 48.6 years, mean body mass index (BMI) was 27.5 (range, 19.7-34.7). Mean follow-up was 16.1 months. The mean preoperative AHI was 32.6 (range, 1.2-104), with the mean lowest oxygen saturation (LSAT) of 79.9% (range, 52%-93%). The mean adjusted preoperative and postoperative systolic blood pressure (SBP) was reduced from 146 ± 15.3 mm Hg to 122 ± 12.5 mm Hg (P < .001), and diastolic blood pressure (DBP) was reduced from 91 ± 10.2 mm Hg to 76 ± 7.8 mm Hg (P < .001). There was a decrease in overall BMI from 27.5 ± 3.6 to 25.5 ± 3.0 (P < .001); however, based on multivariate analysis, the reduction in SBP and DBP was not affected by this BMI reduction. Fifty-eight patients (51.8%) did not require their antihypertensive after surgery. There was poor correlation noted between HTN with AHI, LSAT, and oxygen duration <90%. CONCLUSIONS: Upper airway surgery does reduce SBP and DBP in patients with OSA. LEVEL OF EVIDENCE: 4. Laryngoscope, 128:523-527, 2018.
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Pressão Sanguínea/fisiologia , Hipertensão/cirurgia , Sistema Respiratório/cirurgia , Apneia Obstrutiva do Sono/cirurgia , Adulto , Idoso , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Septo Nasal/cirurgia , Palato/cirurgia , Estudos Prospectivos , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/fisiopatologia , Língua/cirurgia , Resultado do Tratamento , Conchas Nasais/cirurgiaRESUMO
BACKGROUND: Continuous positive airway pressure (CPAP) is typically recommended as first line therapy for obstructive sleep apnea, but the adherence rate of CPAP is problematic. This study's objective was to systematically review the literature relating to CPAP as first line therapy for OSA and compare it to surgical literature on the same topic. METHODS: A systematic review was conducted according to PRISMA guidelines, examining Medline-Ovid, Embase, and Pubmed databases. The primary search objective was to identify all papers reporting the results of (1) randomized clinical trials (RCT) of CPAP for the treatment of adults with OSA; and (2) both randomized and non-randomized clinical trials and case series on the surgical treatment of OSA in adults. A PhD-level biostatistician first screened papers, and then those that met study criteria were retrieved and analyzed using standardized forms for each author. The primary outcomes were adherence rates of CPAP. RESULTS: A total of 82 controlled clinical trials for CPAP and 69 controlled and non-controlled surgery trials were identified for analysis. Variation in CPAP use within reported RCT trials were identified, and the majority of patients in the studies would eventually be considered non-adherent to CPAP. CONCLUSIONS: When considering the numerous patient-related factors that come into play when CPAP is prescribed, the concept of CPAP as gold-standard therapy for OSA should be reconsidered. In many cases surgery can provide a better overall outcome. This study's results suggest that certain patients with OSA may be managed more effectively with surgery than CPAP, without confounding issues of treatment adherence.
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Pressão Positiva Contínua nas Vias Aéreas/métodos , Cooperação do Paciente , Apneia Obstrutiva do Sono/terapia , HumanosRESUMO
To evaluate the success rates of combined Expansion Sphincter Pharyngoplasty and the Anterior Palatoplasty in the treatment of OSA. A two center prospective series of 73 patients with OSA. All patients were >18 years old, retro-palatal obstruction, concentric velo-pharyngeal collapse, BMI < 33, Friedman clinical stage II, with all grades of AHI. The procedure involved the anterior palatoplasty, tonsillectomy and expansion sphincter pharyngoplasty with or without nasal surgery. There were 68 men and 5 women, the mean age was 46.8 years old (range of 25-67 years), mean BMI was 25.5 (range of 20.3-31.2). All patients had pre-operative and post-operative PSG. The AHI improved in all patients, mean AHI improved from 26.3 ± 17.7 to 12.6 ± 5.8 (p < 0.001). There were 20 mild OSA, 33 moderate OSA and 20 severe OSA patients. Twenty-three patients had pre-operative DISE, and 61 patients had nose/palate surgery, while only 12 had palate surgery alone. The overall success rate (50 % reduction and AHI < 20) was 86.3 %. The mean snore scores (VAS) improved from 8.8 ± 1.2 to 2.0 ± 1.3 (p < 0.001). The mean Epworth score improved from 11.5 ± 2.2 to 2.9 ± 2.1 (p < 0.001). Lowest oxygen saturation also improved in all patients. Subjectively, all the patients felt less tiredness. Pre-operative DISE assessment did not seem to confer any advantage over the patients who had no pre-operative DISE (p = 0.027), and patients who had nose/palate surgery seemed to have better success rates compared to those who only had palate surgery (p = 0.081). This combined technique has been shown to be effective in selected group of OSA patients. Level of evidence IV.
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OBJECTIVES/HYPOTHESIS: To illustrate the reliability of the Pang-Rotenberg (PR) sign as a prognosticator of snoring surgery. Our hypothesis was that patients who are PR-positive have better snoring reduction scores and outcomes than PR-negative patients after nose and palate surgery. STUDY DESIGN: A multicenter prospective series of 153 patients with snoring. METHODS: All patients graded the snoring intensity on a visual analog scale (VAS). All 137 patients enrolled had both the nose surgery and palate surgery. The control group consisted of 16 patients who underwent nasal surgery alone. RESULTS: There were 122 men and 15 women, the mean age was 44.6 years old, and mean body mass index was 26.1. There were 15 simple snorers and 122 obstructive sleep apnea patients. Patients who were PR-positive showed significantly better postoperative snoring VAS reduction (from 9.04 to 1.02) compared to those patients who were PR-negative (from 8.91 to 3.14) (P < .001). The mean follow-up time was 7.4 months. The control group had poor snoring VAS reduction from 9.21 to 6.72. After adjusting for covariates that influence the snoring VAS change due to surgery, we found that PR-negative patients achieved an average of 5.78 improvement in snoring VAS, whereas PR-positive patients achieved an average of 8.02 improvement in snoring VAS (P < .001). CONCLUSIONS: The PR sign is a reliable prognosticator of snoring reduction, after combined nose and palate surgery, for patients with troublesome snoring.