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During cooling, conventional martensitic transformation can only be realized from austenite to martensite. Recently, a so-called reentrant martensitic transformation attracted much interest due to an additional transformation from martensite to austenite during further cooling. Obviously, materials with this reentrant transformation will increase the number of physical effects and possible applications. However, until now, only bulk samples have been available, which are not suitable for applications in micro-devices. In this work, we focus on the Co-Cr-Ga-Si system and examine the suitability of this system for the growth of thin films. We observed that the films grow epitaxially on MgO (100) substrates and exhibit a martensitic transformation if deposited at a sufficiently high temperature or with an additional heat treatment. Films within the austenite state are ferromagnetic while films within the martensitic state just exhibit a very low ferromagnetic order.
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INTRODUCTION: Infantile hypertrophic pyloric stenosis is treated by either open pyloromyotomy (OP) or laparoscopic pyloromyotomy (LP). The aim of this meta-analysis was to compare the open versus laparoscopic technique. METHODS: A literature search was conducted from 1990 to February 2021 using the electronic databases MEDLINE, Embase, and Cochrane Central Register of Controlled Trials. Primary outcomes were mucosal perforation and incomplete pyloromyotomy. Secondary outcomes consisted of length of hospital stay, time to full feeds, operating time, postoperative wound infection/abscess, incisional hernia, hematoma/seroma formation, and death. RESULTS: Seven randomized controlled trials including 720 patients (357 with OP and 363 with LP) were included. Mucosal perforation rate was not different between groups (relative risk [RR] LP versus OP 1.60 [0.49-5.26]). LP was associated with nonsignificant higher risk of incomplete pyloromyotomy (RR 7.37 [0.92-59.11]). There was no difference in neither postoperative wound infections after LP compared with OP (RR 0.59 [0.24-1.45]) nor in postoperative seroma/hematoma formation (RR 3.44 [0.39-30.43]) or occurrence of incisional hernias (RR 1.01 [0.11-9.53]). Length of hospital stay (-3.01 h for LP [-8.39 to 2.37 h]) and time to full feeds (-5.86 h for LP [-15.95 to 4.24 h]) were nonsignificantly shorter after LP. Operation time was almost identical between groups (+0.53 min for LP [-3.53 to 4.59 min]). CONCLUSIONS: On a meta-level, there is no precise effect estimate indicating that LP carries a higher risk for mucosal perforation or incomplete pyloromyotomies compared with the open equivalent. Because of very low certainty of evidence, we do not know about the effect of the laparoscopic approach on postoperative wound infections, postoperative hematoma or seroma formation, incisional hernia occurrence, length of postoperative stay, time to full feeds, or operating time.
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Hérnia Incisional , Laparoscopia , Estenose Pilórica Hipertrófica , Piloromiotomia , Abscesso/cirurgia , Hematoma/cirurgia , Humanos , Hérnia Incisional/epidemiologia , Hérnia Incisional/etiologia , Hérnia Incisional/cirurgia , Lactente , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Estenose Pilórica Hipertrófica/cirurgia , Piloromiotomia/efeitos adversos , Piloromiotomia/métodos , Piloro/cirurgia , Seroma , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgiaRESUMO
BACKGROUND: Statistic scripts are often made by mathematicians and cryptic for clinicians or non-mathematician scientists. Nevertheless, almost all research projects necessitate the application of some statistical tests or at least an understanding thereof. The present review aims on giving an overview of the most common statistical terms and concepts. It further ensures good statistical practice by providing a five-step approach guiding the reader to the correct statistical test. METHODS AND RESULTS: First, different types of variables and measurements to describe a data set with means of descriptive statistics are introduced. The basic thoughts and tools of interferential statistics are presented, and different types of bias are discussed. Then in the final paragraph, the most commonly used statistical tests are described. A smartphone app accessible via QR code finally guides the reader in five steps to the correct statistical test, depending on the data used in order to avoid commonly performed mistakes. CONCLUSIONS: The five-step approach sets a new minimal standard for good statistical practice.
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Smartphone , HumanosRESUMO
BACKGROUND: Infantile hypertrophic pyloric stenosis (IHPS) is a disorder of young children (aged one year or less) and can be treated by laparoscopic (LP) or open (OP) longitudinal myotomy of the pylorus. Since the first description in 1990, LP is being performed more often worldwide. OBJECTIVES: To compare the efficacy and safety of open versus laparoscopic pyloromyotomy for IHPS. SEARCH METHODS: We conducted a literature search on 04 February 2021 to identify all randomised controlled trials (RCTs), without any language restrictions. We searched the following electronic databases: MEDLINE (1990 to February 2021), Embase (1990 to February 2021), and the Cochrane Central Register of Controlled Trials (CENTRAL). We also searched the Internet using the Google Search engine (www.google.com) and Google Scholar (scholar.google.com) to identify grey literature not indexed in databases. SELECTION CRITERIA: We included RCTs and quasi-randomised trials comparing LP with OP for hypertrophic pyloric stenosis. DATA COLLECTION AND ANALYSIS: Two review authors independently screened references and extracted data from trial reports. Where outcomes or study details were not reported, we requested missing data from the corresponding authors of the primary RCTs. We used a random-effects model to calculate risk ratios (RRs) for binary outcomes, and mean differences (MDs) for continuous outcomes. Two review authors independently assessed risks of bias. We used GRADE to assess the certainty of the evidence for all outcomes. MAIN RESULTS: The electronic database search resulted in a total of 434 records. After de-duplication, we screened 410 independent publications, and ultimately included seven RCTs (reported in 8 reports) in quantitative analysis. The seven included RCTs enrolled 720 participants (357 with open pyloromyotomy and 363 with laparoscopic pyloromyotomy). One study was a multi-country trial, three were carried out in the USA, and one study each was carried out in France, Japan, and Bangladesh. The evidence suggests that LP may result in a small increase in mucosal perforation compared with OP (RR 1.60, 95% CI 0.49 to 5.26; 7 studies, 720 participants; low-certainty evidence). LP may result in up to 5 extra instances of mucosal perforation per 1,000 participants; however, the confidence interval ranges from 4 fewer to 44 more per 1,000 participants. Four RCTs with 502 participants reported on incomplete pyloromyotomy. They indicate that LP may increase the risk of incomplete pyloromyotomy compared with OP, but the confidence interval crosses the line of no effect (RR 7.37, 95% CI 0.92 to 59.11; 4 studies, 502 participants; low-certainty evidence). In the LP groups, 6 cases of incomplete pyloromyotomy were reported in 247 participants while no cases of incomplete pyloromyotomy were reported in the OP groups (from 255 participants). All included studies (720 participants) reported on postoperative wound infections or abscess formations. The evidence is very uncertain about the effect of LP on postoperative wound infection or abscess formation compared with OP (RR 0.59, 95% CI 0.24 to 1.45; 7 studies, 720 participants; very low-certainty evidence). The evidence is also very uncertain about the effect of LP on postoperative incisional hernia compared with OP (RR 1.01, 95% CI 0.11 to 9.53; 4 studies, 382 participants; very low-certainty evidence). Length of hospital stay was assessed by five RCTs, including 562 participants. The evidence is very uncertain about the effect of LP compared to OP (mean difference -3.01 hours, 95% CI -8.39 to 2.37 hours; very low-certainty evidence). Time to full feeds was assessed by six studies, including 622 participants. The evidence is very uncertain about the effect of LP on time to full feeds compared with OP (mean difference -5.86 hours, 95% CI -15.95 to 4.24 hours; very low-certainty evidence). The evidence is also very uncertain about the effect of LP on operating time compared with OP (mean difference 0.53 minutes, 95% CI -3.53 to 4.59 minutes; 6 studies, 622 participants; very low-certainty evidence). AUTHORS' CONCLUSIONS: Laparoscopic pyloromyotomy may result in a small increase in mucosal perforation when compared with open pyloromyotomy for IHPS. There may be an increased risk of incomplete pyloromyotomy following LP compared with OP, but the effect estimate is imprecise and includes the possibility of no difference. We do not know about the effect of LP compared with OP on the need for re-operation, postoperative wound infections or abscess formation, postoperative haematoma or seroma formation, incisional hernia occurrence, length of postoperative stay, time to full feeds, or operating time because the certainty of the evidence was very low for these outcomes. We downgraded the certainty of the evidence for most outcomes due to limitations in the study design (most outcomes were susceptible to detection bias) and imprecision. There is limited evidence available comparing LP with OP for IHPS. The included studies did not provide sufficient information to determine the effect of training, experience, or surgeon preferences on the outcomes assessed.
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Laparoscopia/métodos , Estenose Pilórica/cirurgia , Piloromiotomia/métodos , Abscesso/epidemiologia , Humanos , Hipertrofia/cirurgia , Hérnia Incisional/epidemiologia , Lactente , Recém-Nascido , Perfuração Intestinal/epidemiologia , Laparoscopia/efeitos adversos , Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Piloromiotomia/efeitos adversos , Piloro/patologia , Piloro/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecção da Ferida Cirúrgica/epidemiologiaRESUMO
The discovery of the high maximum energy product of 59 MGOe for NdFeB magnets is a breakthrough in the development of permanent magnets with a tremendous impact in many fields of technology. This value is still the world record, for 40 years. This work reports on a reliable and robust route to realize nearly perfectly ordered L10 -phase FePt nanoparticles, leading to an unprecedented energy product of 80 MGOe at room temperature. Furthermore, with a 3 nm Au coverage, the magnetic polarization of these nanomagnets can be enhanced by 25% exceeding 1.8 T. This exceptional magnetization and anisotropy is confirmed by using multiple imaging and spectroscopic methods, which reveal highly consistent results. Due to the unprecedented huge energy product, this material can be envisaged as a new advanced basic magnetic component in modern micro and nanosized devices.
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PURPOSE: The Core Outcome Measure Index (COMI) is a brief and multidimensional, patient-orientated outcome questionnaire that assesses chronic pain and quality of life after groin hernia repair. The primary aim of this study was to prospectively assess the COMI-hernia score, over an extended period of time in a single large cohort of patients. METHODS: Two hundred and twenty-eight male patients with inguinal hernia repair were included in the present study. Patients were recruited prospectively with an average follow-up of 3 years. RESULTS: COMI-hernia total and the COMI-hernia pain scores were significantly lower following surgery and remained unchanged over time. Young patients' age (p = 0.043), high preoperative COMI-hernia total score (p = 0.018), and bilateral hernias (p = 0.035) were identified as independent risk factors for adverse outcome after groin hernia repair. Both COMI-hernia total and the COMI-hernia pain scores significantly (p < 2.2*10-16 and p < 1.638*10-11) correlated with patient's satisfaction. CONCLUSIONS: The COMI score reflects a reliable tool to assess the outcome following groin hernia repair.
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Hérnia Inguinal/cirurgia , Herniorrafia/efeitos adversos , Medição da Dor , Dor Pós-Operatória/epidemiologia , Qualidade de Vida , Adulto , Fatores Etários , Idoso , Dor Crônica/epidemiologia , Estudos de Coortes , Seguimentos , Hérnia Inguinal/diagnóstico , Herniorrafia/métodos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/diagnóstico , Estudos Prospectivos , Medição de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários , Fatores de TempoRESUMO
BACKGROUND: It is still not clear if the contralateral side should be explored in children with unilateral inguinal hernias. The primary aim of the present study was to assess the incidence of metachronous contralateral inguinal hernias (MCIHs) in the pediatric population. The second aim was to assess factors associated with increased risk of MCIH development. METHODS: Prospective studies including patients from 0-19 years undergoing unilateral inguinal hernia repair without surgical exploration of the contralateral side between 1947 and April 2020 with a minimal follow-up of one year were searched. Searches included EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials. RESULTS: Seven studies involving 1774 children (1452 boys (82%) and 322 girls (18%) were identified. Overall the incidence of MCIH was 6%. Incidence of MCIH development was significantly higher in children with initial left-sided (9%) versus right-sided (3%) hernia (OR 2.55 with 95% CI from 1.56 to 4.17; Pâ=â0.0002), in female (8%) versus male (4%) children (OR 1.74 with 95% CI from 1.01 to 3.01; Pâ=â0.0469) and in patients with open (14%) versus closed (3%) contralateral processus vaginalis (CPV) (OR 4.17 with 95% CI from 1.25 to 13.9; Pâ=â0.0202). There was no significant difference in MCIH development depending on follow-up duration (follow-up of ≤2 years (i.e. 1-2 years): calculated MCIH incidence 5% (95% CI from 0.00 to 0.11%; 3 studies; 569 patients), follow-up of ≥3 years (i.e. 3-4 years): 6% (95% CI from 0.03 to 0.09; 3 studies, 983 patients)) or patients' age (MCIH incidence in children <1 year: 6.9%; older children: 4.5%; OR 1.87 with 95% CI from 0.97 to 3.62; Pâ=â0.0618). CONCLUSIONS: Overall incidence of MCIH development is 6%. Initial left-sided hernia, female gender and open CPV are risk factors for MCIH development.
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Hérnia Inguinal/epidemiologia , Hérnia Inguinal/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Hérnia Inguinal/diagnóstico , Humanos , Incidência , Lactente , Recém-Nascido , Canal Inguinal/patologia , Masculino , Estudos Prospectivos , Fatores de Risco , Adulto JovemRESUMO
OBJECTIVE: The 24-hour work shifts are newly permitted to first-year surgical residents in the United States. Whether surgery novices' motor activity is affected by sleep deprivation is controversial. MATERIALS AND METHODS: This study assesses sleep deprivation effects in computer-simulated laparoscopy in 20 surgical novices following 24 hours of sleep deprivation and after resting using a virtual-reality trainer. Participants were randomly assigned to perform simulator tests either well rested or sleep deprived first. RESULTS: Of 3 different tasks performed, no significant differences in total time to complete the procedure and average speed of instruments were found. Instrument path length was longer following sleep deprivation (P=0.0435) in 1 of 3 tasks. Error rates (ie, noncauterized bleedings, perforations, etc.), as well as precision, and accuracy rates showed no difference. None of the assessed participants' characteristics affected simulator performance. CONCLUSIONS: Twenty-four hours of sleep deprivation does not affect laparoscopic performance of surgical novices as assessed by computer-simulation.
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Competência Clínica/estatística & dados numéricos , Internato e Residência/normas , Laparoscopia/normas , Transtornos do Sono do Ritmo Circadiano/complicações , Adulto , Idoso , Simulação por Computador , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Destreza Motora/fisiologia , Treinamento por Simulação , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Adulto JovemRESUMO
OBJECTIVE: The aim of the present study was to investigate the outcomes of different treatment options for acute and chronic pilonidal disease in a single large cohort of patients. MATERIALS AND METHODS: Four hundred and twenty-one consecutive patients (171 with chronic disease and 250 with acute abscess formation) who underwent surgery between 2003 and 2012 were included in the present study. Primary outcomes included symptomatic recurrence, time to wound healing, and time off from work. The median follow-up was 5.3 years. RESULTS: In patients with acute abscess formation, the relapse rate was significantly higher (P = 0.0001) if they were treated with abscess excision (38.9%) compared with a wide local excision (13.3%). Time to relapse was significantly longer (P = 0.0205) in patients treated with wide local excision (median 7 vs 3 months), whereas time to wound healing and the days off from work were similar among groups. In chronic disease, the relapse rate was similar in patients treated with wide local excision followed by secondary wound healing (11.3%) when compared with patients treated with limited excision (27.6%) or wide excision with primary wound closure (26.8%). The time to wound healing was shortest in patients with primary wound closure following wide local excision, and the time off from work was not significantly different between groups. CONCLUSION: Wide local excision with secondary wound healing seems to be the favorable operation method for acute and chronic pilonidal disease.