bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of rotating hinge implants in revision total knee arthroplasty
Authors: Pasquier Gilles , Ehlinger Matthieu , Mainard Didier 
Published: June 2019

Hinged implants are the most constrained knee replacement prostheses. They are very useful in complex cases of total knee arthroplasty (TKA) revision. Hinged implants have evolved with rotating bearings and modularity that allows local joint reconstruction or segmental bone replacement. They are required when significant instability persists in cases with inadequate collateral ligaments and significant flexion laxity. They are now used when a large bone defect is reconstructed, or when bone fixation of the implant is questionable especially in the metaphyseal zone. The use of hinged implants in TKA revision is associated with high complication rates. Published outcomes differ based on the patients’ aetiology. The outcomes of rotating-hinged implants used in septic revisions or salvage situations are poorer than other types of revision and have a higher complication rate. The poor general health of these patients is often a limitation. Despite these relatively poor results, hinged implants continue to have a place in revision surgery to solve major instability or to obtain stable bone fixation of an implant when the metaphysis is filled with bone grafts or porous devices. Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180070
Comparison of gait kinematics in total and unicondylar knee replacement surgery
Authors: Agarwal A , Miller S , Hadden W , Johnston L , Wang W , Arnold G , Abboud RJ 
Published: June 2019

Introduction This study is aimed to compare kinematic gait data of patients who have undergone total and unicondylar knee replacement. Materials and methods This single-surgeon retrospective cohort study evaluated 13 patients with unilateral total knee arthroplasty (TKA) and 14 unicondylar knee arthroplasty (UKA). Gait analysis was carried out using a Vicon motion analysis system. The limits of knee flexion during stance phase, at heel strike and at loading response were measured. Results The total range of motion of the UKA knees was significantly greater than the TKA knees. UKA knees exhibited significantly greater knee extension during the stance phase than the TKA knees. Unlike TKA, UKA knees demonstrated improved knee flexion during the gait cycle when compared to the contralateral non-operated knee. The hips also demonstrated near normal hip flexion in UKA patients. Predictably, UKA knees had significantly greater varus compared with TKA in the coronal plane. Spatiotemporal variables demonstrated similar walking speed and step length to aid a fair comparison between knee replacement groups. Conclusions The UKA knees moved more physiologically in the sagittal plane with a greater range of motion during gait. Despite having a stiff gait pattern, the patients undergoing TKA demonstrated a more neutral alignment in the coronal plane. Neither type of knee arthroplasty restored knee kinematics to those of the non-operated side.
Validation of the acute cholecystectomy rate as a quality indicator for emergency general surgery using the SWORD database
Authors: Palser TR , Navarro AP , Swift S , Beckingham IJ 
Published: June 2019

Introduction Despite an increasing emphasis on data-driven quality improvement, few validated quality indicators for emergency surgical services have been published. The aims of this study therefore were: 1) to investigate whether the acute cholecystectomy rate is a valid process indicator; and 2) to use this rate to examine variation in the provision of acute cholecystectomy in England. Materials and methods The Surgical Workload and Outcomes Research Database (SWORD), derived from the Hospital Episode Statistics database, was interrogated for the 2012–2017 financial years. All adult patients admitted with acute biliary pancreatitis, cholecystitis or biliary colic to hospitals in England were included and the acute cholecystectomy rate in each one examined. Results A total of 328,789 patients were included, of whom 42,642 (12.9%) underwent an acute cholecystectomy. The acute cholecystectomy rate varied significantly between hospitals, with the overall rate ranging from 1.2% to 36.5%. This variation was consistent across all disease groupings and time periods, and was independent of the annual number of procedures performed by each NHS trust. In 41 (29.9%) trusts, fewer than one in ten patients with acute gallbladder disease underwent cholecystectomy within two weeks. Conclusions The acute cholecystectomy rate is easily measurable using routine administrative datasets, modifiable by local services and has a strong evidence base linking it to patient outcomes. We therefore advocate that it is an ideal process indicator that should be used in quality monitoring and improvement. Using it, we identified significant variation in the quality of care for acute biliary disease in England.
The role of intraoperative cholangiography in patients undergoing laparoscopic cholecystectomy for acute gallstone pancreatitis: is magnetic resonance cholangiopancreatography needed?
Authors: Thacoor A , Pike TW , Pathak S , Dixon J , Macutkiewicz C , Smith AM 
Published: June 2019

Introduction Intraoperative cholangiography is sporadically used in patients undergoing laparoscopic cholecystectomy to delineate common bile duct anatomy and exclude retained stones. In patients with acute gallstone pancreatitis, intraoperative cholangiography may reduce the need for preoperative magnetic resonance cholangiopancreatography. Materials and methods A retrospective review of a prospectively collected patient database was undertaken over a 15-year period. The primary objective was to evaluate intraoperative assessment of the common bile duct with intraoperative cholangiography in patients with acute gallstone pancreatitis. Results A total of 2215 patients underwent laparoscopic cholecystectomy between October 1998 and December 2013; 113 patients (of whom 77 were women) with a mean age of 54 years (range 16–88 years) were diagnosed with acute gallstone pancreatitis. Of these, 102 patients (90%) underwent laparoscopic cholecystectomy with intraoperative cholangiography, which was normal in 89 cases. Thirteen patients had choledocholithiasis on intraoperative cholangiography, 11 of whom were managed with concomitant trans-cystic duct exploration and clearance. Two patients required postoperative endoscopic retrograde cholangiopancreatography. Conclusions In patients diagnosed with acute gallstone pancreatitis, it is reasonable to proceed directly to surgery using intraoperative cholangiography on the same admission as the definitive assessment of the common bile duct. This negates the need for magnetic resonance cholangiopancreatography and can translate into cost savings and reduced length of stay.
Daycase trauma list: a safe and cost-effective service delivery
Authors: Athar MS , Fazal MA , Ashwood N , Arealis G , Buchanan D , Okoth FH 
Published: June 2019

Introduction Daycase trauma surgery is an evolving and a novel approach. The aim of our study was to report our experience of daycase trauma surgery with a focus on safety, patient experience, complications and limitations. Material and methods Patients scheduled and operated on a daycase trauma list from January 2013 to December 2016 were included in the study. Age, sex, case mix, readmissions within 48 hours, complications, patient satisfaction, reasons for overnight stay and cost effectiveness were evaluated. Results A total of 229 procedures were carried out. The mean age of the patients was 44.3 years (range 16–85 years) . There were 128 men and 101 women, 178 upper-limb and 51 lower-limb cases. Only 2.6% of the patients had stayed overnight for pain control, physiotherapy and neurological observations; 94.5% of the patients were satisfied. The mean visual analogue scale score for satisfaction was 8.7. There were no admissions within 48 hours of discharge and one complication with failure of ankle fixation. The estimated cost saving was £65,562. Conclusion We conclude that a daycase trauma service is safe, cost effective, and yields high patient satisfaction. It reduces the burden on hospital beds and a wide range of upper- and lower-limb cases can be performed as daycase trauma surgery with adequate planning and teamwork.
Enhancing the emergency general surgical service: an example of the aggregation of marginal gains
Authors: Panagiotopoulou IG , Bennett JMH , Tweedle EM , Di Saverio S , Gourgiotis S , Hardwick RH , Wheeler JMD , Justin Davies R 
Published: June 2019

Introduction We aimed to enhance the emergency general surgical service in our high-volume centre in order to reduce four-hour target breaches, to expedite senior decision making and to avoid unnecessary admissions. Materials and methods The aggregation of marginal gains theory was applied. A dual consultant on-call system was established by the incremental employment of five emergency general surgeons with a specialist interest in colorectal or oesophagogastric surgery. A surgical ambulatory care unit, which combines consultant-led clinical review with dedicated next-day radiology slots, and a dedicated working week half-day gastrointestinal urgent theatre session were instituted to facilitate ambulatory care pathways. Results The presence of two consultant surgeons being on call during weekday working hours decreased the four-hour target breaches and allowed consultant presence in the surgical ambulatory care clinic and the gastrointestinal urgent theatre list. Of 1371 surgical ambulatory care clinic appointments within 30 months, 1135 (82.7%) avoided a hospital admission, corresponding to savings of £309,752 . The coordinated functioning of the surgical ambulatory care clinic and the gastrointestinal urgent theatre list resulted in statistically significantly reduced hospital stays for patients operated for abscess drainage (gastrointestinal urgent theatre median 11 hours (interquartile range 3, 38) compared with emergency median 31 hours (interquartile range 24, 53), P < 0.001) or diagnostic laparoscopy/appendicectomy (gastrointestinal urgent theatre median 52 hours (interquartile range 41, 71) compared with emergency median 61 hours (interquartile range 43, 99), P = 0.005). Overnight surgery was reduced with only surgery that was absolutely necessary occurring out of hours. Conclusion The expansion of the ‘traditional’ on-call surgical team, the establishment of the surgical ambulatory care clinic and the gastrointestinal urgent theatre list led to marginal gains with a reduction in unnecessary inpatient stays, expedited decision making and improved financial efficiency.
Tłumacze bez Granic a status tłumacza
Authors: Masłowska Patrycja 
Published: May 2019

The objective of the present article is to analyse the influence of the organisation Translators Without Borders on the status of its volunteers: translators and community interpreters. The first chapter concerns main aspects of the translator's status. The second one presents briefly the types of Translators Without Borders activities, while the next one focuses on the characteristics of the types of translator's and interpreter's work for the organization. The last chapter includes the analysis of the translator's and interpreter's status aspects that are susceptible to impact of the described organization’s activities. Conclusions are ambiguous as the main reason of the Translators Without Borders foundation was not to improve the translator's status. However, membership may be beneficial under certain conditions.
Chaotic Mixing Analyses by Distribution Matrices
Authors: Anderson Patrick D. , Meijer Han E. H. 
Published: May 2019

Abstract
Distributive fluid mixing in laminar flows is studied using the concept of concentration distribution mapping matrices, which is based on the original ideas of Spencer & Wiley [1], describing the evolution of the composition of two fluids of identical viscosity with no interfacial tension. The flow domain is divided into cells, and large-scale variations in composition are tracked by following the cell-average concentrations of one fluid using the mapping method of Kruijt et al. [2]. An overview of recent results is presented here where prototype two- and three-dimensional time-periodic mixing flows are considered. Efficiency of different mixing protocols are compared and for a particular example the (possible) influence of fluid rheology on mixing is studied. Moreover, an extension of the current method including the microstructure of the mixture is illustrated. Although here the method is illustrated making use of these simple flows, more practical, industrial mixers like twin screw extruders can be studied using the same approach.
Calibration of a Commercial Kneader for Rheological Applications
Authors: Kealy Tim , Tiu Carlos 
Published: May 2019

Abstract
In the case of some highly viscous fluids, or thick pastes (such as those exhibiting high yield stress and/or high plastic viscosity), neither rotational nor tube type viscometers are suitable for rheological characterisation. Due to their capacity for generating and maintaining high torque or high rates of rotation, kneaders and mixers can often engender shear rates in excess of those of conventional rotational viscometers. Often these devices are instrumented, to measure and record the rate of rotation of the mixing blades and the related torque on the shaft turning the blades. The major problem facing users of these mixers lies in data interpretation, specifically in relating rate of rotation and torque data to shear rate and shear stress respectively. If it were possible to obtain such relationships, useful rheological data could be generated with instrumented mixers.
Blood Electrical Impedance Closely Matches Whole Blood Viscosity as Parameter of Hemorheology and Inflammation
Authors: Pop G.A.M. , Hop W.J. , Moraru L. , van der Jagt M. , Quak J. , Dekkers D. , Chang Z. , Gijsen F.J. , Duncker D.J. , Slager C.J. 
Published: May 2019

AbstractRed blood cell aggregation (RBCa) is a sensitive inflammation marker. RBCa determination from erythrocyte sedimentation rate, ESR, is used since long, but is unspecific unless corrected for hematocrit, Ht. Whole blood viscosity measurement at low shear rate is also sensitive to RBCa but is cumbersome to apply. To investigate whether electrical blood impedance, being sensitive to spatial red cell distribution, can be a good alternative to determine RBCa in low shear conditions. Blood was collected from 7 healthy volunteers. From each 16 different samples were prepared with 4 different Ht’s and with 4 different fibrinogen concentrations. Viscosity was measured at low shear rate (4.04 s-1) with a rotational viscometer at 37˚C. Electrical blood impedance was measured during similar shear conditions and temperature in a specially designed cuvette. ESR was determined according to Westergren. A logarithmic increase of viscosity as well as of capacitance, Cm, is seen when fibrinogen rises and an exponential increase when Ht rises. However, ESR shows a logarithmic decrease with increasing Ht and an exponential increase when fibrinogen rises. The viscosity could be accurately described using an exponential model. Under similar low shear conditions and temperature in-vitro, either whole blood viscosity or electrical blood capacitance reflect red blood cell aggregation due to fibrinogen and Ht variation in a similar way.
Characterization of the Linear Viscoelastic Region in Suspensions of Zirconium Oxide: Cohesive Energy Obtained From the Critical Parameters
Authors: Megías-Alguacil David 
Published: May 2019

Abstract
The linear viscoelastic regions (L.V.R.) of suspensions of zirconium oxide particles were determined and characterized through the so-called "critical parameters". These are the values of shear-stress and strain at the crossover between the linear and the non-linear viscoelastic responses. From these magnitudes, the cohesive energy between the particles is calculated as a function of volume fraction of solids and at different electrolyte concentrations. The oscillatory measurements were carried out using a constant-stress rheometer at a fixed frequency of 1 Hz and increasing shear-stress. The suspensions cover a volume fraction range between 3% - 25% with electrolyte (sodium chloride) concentrations of 10-1 M, 10−2 M, 10−3 M and 10−5 M. Two different kinds of ZrO2 particles were used: commercially obtained -with no defined geometry- and spheres synthesized by us following the method described by Aiken, Hsu and Matijevic [1].
Discrete Relaxation Spectrum and K-BKZ Constitutive Equation for PVC, NBR and Their Blends
Authors: Sodeifian Gholamhossein , Haghtalab Ali 
Published: May 2019

Abstract
Frequency sweep experiments were performed on poly(vinyl chloride) (PVC) and acrylonitrile butadiene rubber (NBR) as well as their miscible blends PVC/NBR (70/30), PVC/NBR (50/50), and PVC/NBR (30/70) in oscillatory shear. The samples were prepared by mechanical blending at 160˚C. In order to investigate the validity of time temperature superposition (TTS) principle the loss angle δ versus the logarithm of the absolute value of the complex modulus, G*, were plotted. It was shown that the TTS principle is not valid for the above-mentioned polymer materials and therefore they are not thermorheologically simple. Master curves of PVC, NBR, and PVC/NBR (50/50) blend were therefore obtained approximately. Using a nonlinear regression method, discrete relaxation spectra were determined for PVC, NBR, and PVC/NBR (50/50). To study non-linear viscoelasticity behavior, the experiments of steady shear, start up steady shear, and step strain were carried out. The damping function was determined by the step strain experiments. Using K-BKZ constitutive equation, the shear viscosity and the shear stress growth function were calculated from the discrete relaxation spectra and the damping function and then compared to experimental data. The K-BKZ constitutive equation provides very good prediction over the entire range of experimental results.
Rheological Testing of Xerographic Liquid Inks: A Need for Printing Technology
Authors: Valverde J.M. , Pérez A.T. , Castellanos A. , Viturro R.E. 
Published: May 2019

Abstract
Rheological properties of xerographic liquid inks of different concentrations of solid particles have been tested. Generally we have found that viscosity decreases with increasing shear rate, i.e. the system is pseudoplastic as corresponds to the break down of aggregated particles by the applied shear. The viscosity of inks may vary in orders of magnitude depending on solids concentration, reaching up values of ~ 108 Pas for solids concentration of 40 wt%. The existence of a yield critical stress has been discussed and we estimate that it increases exponentially with solids concentration. We have looked for possible differences in the rheological behavior of ink samples obtained either diluting more concentrated inks or drying less concentrated ones. Concentration and dilution of xerographic inks do not change their rheological properties meaning that the microscopic structure of the concentrated dispersion is broken (when diluting) and recovered (when drying) reversibly. On the other hand processed ink (previously subjected to high mechanical and electrostatic stresses) behaves differently than non-processed ink. The properties of processed inks are not totally recovered when diluting, manifesting itself in a higher effective apparent viscosity. This result should be of main concern to liquid ink based printing technologies, for which elimination of waste by recycling processed ink is a major goal.
A Quick Guide to Better Viscosity Measurements of Highly Viscous Fluids
Authors: Schweizer Thomas 
Published: May 2019

Abstract
The performance of tests with elastic liquids at high shear rates is cumbersome due to viscous dissipation heating, high normal forces, and - above all - edge fracture. This paper shows how such measurements can be improved and simplified over the conventional cone-plate technique by using a partitioned plate. For a polystyrene melt with zero shear viscosity 44.5 kPas at 190˚C, steady state viscosities can be obtained up to 100 s−1. For samples with twice the diameter of the sensing area of the tool, the strain beyond which disturbances can be noticed is about 2 - 3 times higher than for conventional cone-plate. As a consequence of the design, precise viscosity measurements can be made without knowing the exact radius of the sample and without well centring it. This geometry is ideal for quick and dirty loading. Drawbacks are that the tool requires regular cleaning of the ring gap, that it can only be fitted to rheometers with a non-displacing force measuring cell (force rebalance transducer), and that it is not suited to measure low viscous systems such as polymer solutions.
Present status of prophylactic thyroidectomy in pediatric multiple endocrine neoplasia 2: a nationwide survey in Japan 1997–2017
Authors: Matsushita Rie , Nagasaki Keisuke , Ayabe Tadayuki , Miyoshi Yoko , Kinjo Saori , Haruna Hidenori , Ihara Kenji , Hasegawa Tomonobu , Ida Shinobu , Ozono Keiichi , Minamitani Kanshi 
Published: May 2019

Abstract

Background
In Japan, prophylactic thyroidectomy involves out-of-pocket expense. The American Thyroid Association (ATA) recommends prophylactic thyroidectomy for medullary thyroid carcinoma (MTC) during early childhood in patients with multiple endocrine neoplasia type 2 (MEN2). The ATA reports a high frequency of postoperative complications in childhood, which also influenced the delay of prophylactic thyroidectomy in Japan.

Methods
This retrospective study of multiple medical centers in Japan included individuals aged <20 years diagnosed with germline RET mutations between 1997 and 2017. The onset and onset possibility were defined based on confirmed lesions or calcitonin levels. The definition of risk and prophylactic thyroidectomy were based on the ATA 2015 revised guideline.

Results
Twenty-one patients with MEN2 were enrolled (highest risk, n = 5; high risk, n = 5; and moderate risk, n = 11). The cumulative incidence of the onset/onset possibility reached 50% at 5 and 8 years and 100% at 9 years and 17 years in high- and moderate-risk patients, respectively. Of 7 patients with MEN2A, 71% underwent prophylactic thyroidectomy. Only one 5-year-old patient (C634Y) had increased serum calcitonin level after prophylactic thyroidectomy in the MEN2A group. The only permanent complication, which did not occur in patients who underwent total thyroidectomy alone, was hypoparathyroidism (33% of patients). This permanent complication occurred with clinically developed MTC. No permanent postoperative complications occurred in patients aged 5–6 years.

Conclusions
Prophylactic thyroidectomy reduces recurrence and postoperative complications in pediatric patients with MEN2. Early thyroidectomy based on only calcitonin level could possibly reduce thyroidectomy delay.
Competitive balance with unbalanced schedules
Authors: Lee Young Hoon , Kim Yongdai , Kim Sara 
Published: May 2019

Abstract
Many empirical studies on competitive balance (CB) use the ratio of the actual standard deviation to the idealized standard deviation of win percentages (RSD). This paper suggests that empirical studies that use RSD to compare CB among different leagues are invalid, but that RSD may be used for time-series analysis on CB in a league if there are no changes in season length. When schedules are unbalanced and/or include interleague games, the final winning percentage is a biased estimator of the true win probability. This paper takes a mathematical statistical approach to derive an unbiased estimator of within-season CB that can be applied to not only balanced but also unbalanced schedules. Simulations and empirical applications are also presented, which confirm that the debiasing strategy to obtain the unbiased estimator of within-season CB is still effective for unbalanced schedules.