110 research outputs found

    Prominent bulk pinning effect in the MgB_2 superconductor

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    We report the magnetic-field dependence of the irreversible magnetization of the recently discovered binary superconductor MgB2_{2}. For the temperature region of T<0.9TcT< 0.9T_c, the contribution of the bulk pinning to the magnetization overwhelms that of the surface pinning. This was evident from the fact that the magnetization curves, M(H)M(H), were well described by the critical-state model without considering the surface pinning effect. It was also found that the M(H)M(H) curves at various temperatures scaled when the field and the magnetization were normalized by the characteristic scaling factors H∗(T)H^\ast(T) and M∗(T)M^\ast(T), respectively. This feature suggests that the pinning mechanism determining the hysteresis in M(H)M(H) is unique below T=TcT=T_c.Comment: 4pages and 4 figures. Phys. Rev. B (accepted

    The Ginninderra CH4 and CO2 release experiment: An evaluation of gas detection and quantification techniques

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    A methane (CH4) and carbon dioxide (CO2) release experiment was held from April to June 2015 at the Ginninderra Controlled Release Facility in Canberra, Australia. The experiment provided an opportunity to compare different emission quantification techniques against a simulated CH4 and CO2 point source release, where the actual release rates were unknown to the participants. Eight quantification techniques were assessed: three tracer ratio techniques (two mobile); backwards Lagrangian stochastic modelling; forwards Lagrangian stochastic modelling; Lagrangian stochastic (LS) footprint modelling; atmospheric tomography using point and using integrated line sensors. The majority of CH4 estimates were within 20% of the actual CH4 release rate (5.8 g/min), with the tracer ratio technique providing the closest estimate to both the CH4 and CO2 release rates (100 g/min). Once the release rate was known, the majority of revised estimates were within 10% of the actual release rate. The study illustrates the power of measuring the emission rate using multiple simultaneous methods and obtaining an ensemble median or mean. An ensemble approach to estimating the CH4 emission rate proved successful with the ensemble median estimate within 16% for the actual release rate for the blind release experiment and within 2% once the release rate was known. The release also provided an opportunity to assess the effectiveness of stationary and mobile ground and aerial CH4 detection technologies. Sensor detection limits and sampling rates were found to be significant limitations for CH4 and CO2 detection. A hyperspectral imager\u27s capacity to image the CH4 release from 100 m, and a Boreal CH4 laser sensor\u27s ability to track moving targets suggest the future possibility to map gas plumes using a single laser and mobile aerial reflector

    Forearm rotation improves after corrective osteotomy in patients with symptomatic distal radius malunion

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    Objectives: Distal radius malunion can result in pain and functional complaints. One of the functional problems that can affect daily life is impaired forearm rotation. The primary aim of this study was to investigate the effect of corrective osteotomy for distal radius malunion on forearm rotation at 12 months after surgery. We secondarily studied the effect on grip strength, radiological measurements, and patient-reported outcome measurements (PROMs). Patients and methods: This cohort study analysed prospectively collected data of adult patients with symptomatic distal radius malunion. All patients underwent corrective osteotomy for malunion and were followed for 1 year. We measured forearm rotation (pronation and supination) and grip strength and analysed radiographs. PROMs consisted of the Patient-Rated Hand/Wrist Evaluation (PRWHE) questionnaire, Visual Analogue Scale for pain, and satisfaction with hand function. Results:Preoperative total forearm rotation was 112° (SD: 34°), of which supination of 49° (SD: 25°) was more impaired than pronation of 63° (SD: 17°). Twelve months after surgery, an unpaired Student's t-test showed a significant improvement of total forearm rotation to 142° (SD: 17°) (p &lt; 0.05). Pronation improved to 72° (SD: 10°), and supination to 69° (SD: 13°) (p &lt; 0.05). Grip strength, PROMs, as well as inclination and volar tilt on radiographs improved significantly during the first year after surgery (p &lt; 0.05). Conclusion: In patients with reduced forearm rotation due to distal radius malunion, corrective osteotomy is an effective treatment that significantly improves forearm rotation. In addition, this intervention improves grip strength, the PRWHE-score, pain, and satisfaction with hand function.</p

    Preoperative Indicators of the Effectiveness of Surgical Release in Patients with de Quervain Disease:A Prospective Cohort Study

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    Background: A significant proportion of patients report persistent pain after surgical release for de Quervain disease (DQ). This study aimed to investigate the effectiveness of a surgical release for DQ and to identify the preoperative factors associated with pain after a surgical release for DQ. Methods: This prospective cohort study included 707 patients who underwent surgical release and completed a visual analogue scale questionnaire (VAS; range 0 to 100). We used a paired t test to analyze the effectiveness of the surgical release on pain at 3 months postoperatively compared with the preoperative measure. A hierarchical multivariable linear regression model was created to investigate the contribution of patient-related and disease-related characteristics to postoperative pain. Results: All VAS domains showed improvement after surgical release. On average, the mean VAS pain decreased by 44 points (95% CI, 42, 46). Smoking (B = 6.37; P &lt; 0.01), younger age (B = -0.35; P &lt; 0.01), longer duration of complaints (B = 0.13; P &lt; 0.01), concomitant surgery (B = 14.40; P &lt; 0.01), and higher VAS pain scores at intake (B = 0.15; P &lt; 0.01) were associated with worse VAS pain scores postoperatively. Together, the variables explained 11% of the variance in mean VAS pain score at 3 months follow-up. Conclusions: This study confirms that surgical treatment for DQ significantly reduces patient-reported pain. Smoking, younger age, concomitant surgery, duration of complaints, and higher VAS pain scores at intake are associated with worse patient-reported pain 3 months after surgical release. However, the small effects suggest that these factors should not be considered the only important factors. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.</p

    Patient-Reported Outcomes and Function after Surgical Repair of the Ulnar Collateral Ligament of the Thumb

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    Purpose: The purpose of this study was to report prospectively collected patient-reported outcomes of patients who underwent open thumb ulnar collateral ligament (UCL) repair and to find risk factors associated with poor patient-reported outcomes. Methods: Patients undergoing open surgical repair for a complete thumb UCL rupture were included between December 2011 and February 2021. Michigan Hand Outcomes Questionnaire (MHQ) total scores at baseline were compared to MHQ total scores at three and 12 months after surgery. Associations between the 12-month MHQ total score and several variables (i.e., sex, injury to surgery time, K-wire immobilization) were analyzed. Results: Seventy-six patients were included. From baseline to three and 12 months after surgery, patients improved significantly with a mean MHQ total score of 65 (standard deviation [SD] 15) to 78 (SD 14) and 87 (SD 12), respectively. We did not find any differences in outcomes between patients who underwent surgery in the acute (&lt;3 weeks) setting compared to a delayed setting (&lt;6 months). Conclusions: We found that patient-reported outcomes improve significantly at three and 12 months after open surgical repair of the thumb UCL compared to baseline. We did not find an association between injury to surgery time and lower MHQ total scores. This suggests that acute repair for full-thickness UCL tears might not always be necessary. Type of study/level of evidence: Therapeutic II.</p

    Genes in the Ureteric Budding Pathway: Association Study on Vesico-Ureteral Reflux Patients

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    Vesico-ureteral reflux (VUR) is the retrograde passage of urine from the bladder to the urinary tract and causes 8.5% of end-stage renal disease in children. It is a complex genetic developmental disorder, in which ectopic embryonal ureteric budding is implicated in the pathogenesis. VUR is part of the spectrum of Congenital Anomalies of the Kidney and Urinary Tract (CAKUT). We performed an extensive association study for primary VUR using a two-stage, case-control design, investigating 44 candidate genes in the ureteric budding pathway in 409 Dutch VUR patients. The 44 genes were selected from the literature and a set of 567 single nucleotide polymorphisms (SNPs) capturing their genetic variation was genotyped in 207 cases and 554 controls. The 14 SNPs with p<0.005 were included in a follow-up study in 202 cases and 892 controls. Of the total cohort, ∼50% showed a clear-cut primary VUR phenotype and ∼25% had both a duplex collecting system and VUR. We also looked for association in these two extreme phenotype groups. None of the SNPs reached a significant p-value. Common genetic variants in four genes (GREM1, EYA1, ROBO2 and UPK3A) show a trend towards association with the development of primary VUR (GREM1, EYA1, ROBO2) or duplex collecting system (EYA1 and UPK3A). SNPs in three genes (TGFB1, GNB3 and VEGFA) have been shown to be associated with VUR in other populations. Only the result of rs1800469 in TGFB1 hinted at association in our study. This is the first extensive study of common variants in the genes of the ureteric budding pathway and the genetic susceptibility to primary VUR

    Transitional Care for Patients with Congenital Colorectal Diseases: An EUPSA Network Office, ERNICA, and eUROGEN Joint Venture

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    Background: Transition of care (TOC; from childhood into adulthood) of patients with anorectal malformations (ARM) and Hirschsprung disease (HD) ensures continuation of care for these patients. The aim of this international study was to assess the current status of TOC and adult care (AC) programs for patients with ARM and HD. Methods: A survey was developed by members of EUPSA, ERN eUROGEN, and ERNICA, including patient representatives (ePAGs), comprising of four domains: general information, general questions about transition to adulthood, and disease-specific questions regarding TOC and AC programs. Recruitment of centres was done by the ERNs and EUPSA, using mailing lists and social media accounts. Only descriptive statistics were reported. Results: In total, 82 centres from 21 different countries entered the survey. Approximately half of them were ERN network members. Seventy-two centres (87.8%) had a self-reported area of expertise for both ARM and HD. Specific TOC programs were installed in 44% of the centres and AC programs in 31% of these centres. When comparing centres, wide variation was observed in the content of the programs. Conclusion: Despite the awareness of the importance of TOC and AC programs, these programs were installed in less than 50% of the participating centres. Various transition and AC programs were applied, with considerable heterogeneity in implementation, content and responsible caregivers involved. Sharing best practice examples and taking into account local and National Health Care Programs might lead to a better continuation of care in the future. Level of Evidence: III

    Surgical stabilization for symptomatic carpometacarpal hypermobility; a randomized comparison of a dorsal and a volar technique and a cohort of the volar technique

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    BACKGROUND: Hypermobility of the first carpometacarpal joint is mostly surgically treated with a volar approached stabilization by Eaton, but recent studies indicate the importance of the dorsoradial and intermetacarpal ligaments (DRL and IML) for carpometacarpal joint stability. The aim of this study was to compare a dorsal and volar technique for primary carpometacarpal hypermobility regarding pain and functional outcome. METHODS: Patients with non-degenerative, painful carpometacarpal hypermobility were included and were randomly assigned to either the volar technique using the FCR, or a dorsal technique using the ECRL. After premature termination of the trial, we followed all patients treated with the volar approach. Pain, strength, and ADL function using DASH and Michigan Hand Questionnaires (MHQ) were measured at baseline and 3 and 12 months after surgery. RESULTS: After including 16 patients, the randomized trial comparing the volar and dorsal technique was terminated because of significant increased pain in the dorsal group. Although none of the other outcome measures were significant in the underpowered comparison, in line with the pain scores, all variables showed a trend towards a worse outcome in the dorsal group. Between 2009 and 2012, 57 thumbs were surgically stabilized. We found significant better pain and MHQ scores, and after 1 year improved grip and key pinch strength. Patients returned to work within 8 (±7) weeks, of which 85 % in their original job. CONCLUSIONS: Surgical stabilization of the thumb is an effective method for patients suffering from hypermobility regarding pain, daily function, and strength. We recommend a volar approach. Level of Evidence: Level I, therapeutic stud

    Author Correction: The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data

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    The following authors were omitted from the original version of this Data Descriptor: Markus Reichstein and Nicolas Vuichard. Both contributed to the code development and N. Vuichard contributed to the processing of the ERA-Interim data downscaling. Furthermore, the contribution of the co-author Frank Tiedemann was re-evaluated relative to the colleague Corinna Rebmann, both working at the same sites, and based on this re-evaluation a substitution in the co-author list is implemented (with Rebmann replacing Tiedemann). Finally, two affiliations were listed incorrectly and are corrected here (entries 190 and 193). The author list and affiliations have been amended to address these omissions in both the HTML and PDF versions
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