Previously Unrecognized Source of Error in the Change in Maximum Total Point Motion to Determine Continuous Migration of Unstable Tibial Baseplates

In radiostereometric analysis (RSA), continuous migration denoted as ΔMTPM is the difference between maximum total point motion (MTPM) at 2 years relative to time zero and MTPM at 1 year relative to time zero. Continuous migration has been used to diagnose tibial baseplates as stable versus unstable when compared to a specified stability limit (i.e. value of ΔMTPM). If the same point experiences MTPM at 2 years and at 1 year (usually the case for marker-based RSA), then an implicit assumption is that the migration path between 2 years and 1 year is the same as the path between 1 year and time zero. This paper uses vector analysis to demonstrate a source of error in ΔMTPM not previously recognized and estimates the error magnitude based on the interplay of independent variables which affect the error. The two independent variables which affect the error are the angle between the two migration vectors (i.e., MTPM between time zero and 2 years and MTPM between time zero and 1 year) and the difference in magnitude of the two vectors. The relative error increased in an absolute sense as the angle between the vectors increased and decreased for larger differences in the magnitudes of the two vectors. For magnitude ratios ranging from 1.25 to 2, relative errors ranged from -21% to -3% at 10° and from -78% to -42% at 60°, respectively. Knowledge of these errors highlights a limitation in the use of ΔMTPM not previously recognized.

To Find out the Value of Hypermobility in Down’s Syndrome

Background: Down syndrome, the result of trisomy of chromosome 21, is one of the most common chromosomal abnormalities. Patients have a characteristic 8 facial appearance, variable levels of intelligence and self-care skills, and a variety of associated medical conditions. Orthopaedic manifestations occur frequently; most are related to hypotonia, joint hypermobility, and ligamentous laxity. Objective: Aim of the study is to find out the value of hyper mobility in down’s syndrome. Methodology: 30 Subjects including in my study ,study duration is 4 weeks, study setting is Maithree Special School, NIEPMD, REC Centre SRM Hospital. Outcome Measures: Beighton Scale, Goniometre Results: This beighton scale consists of goniometer measurement of thumb, metacarcophalangeal joints ,elbow joint , knee joints,trunk flexion .total point (9) point.50%of sample was scored 9 point.10%of sample was scored 8 point.7%of sample was s cored 7 points.35%of sample was scored 6 points. Conclusion: This study concluded that Down’s Syndrome children has hypermobility which needs to be investigated early and treated for better quality of life.

Students’ Cognitive Test Anxiety and Secondary School Examination Performance: Moderating Effect of Gender and School Sector

Despite a bulk of research in international context investigating the relationship of cognitive test anxiety with students’ academic performance, little work has yet been done in this area on samples of students in Pakistan. This correlational design study was, therefore, conducted to examine the relationship between secondary school students’ cognitive test anxiety and their examination performance in educational context of Pakistan and to ascertain how the direction and/or strength of this relationship may be moderated by students’ gender and their school sector. Data were collected on students’ cognitive test anxiety, total obtained marks in SSC examination and obtained marks in English along with students’ gender and school sector from 1712 mixed ability students enrolled in year 11 in 91 public and private institutions. Both the descriptive and inferential statistical techniques (i.e., Mean, SD and Independent samples t-test) along with Pearson’s R correlations and hierarchical multiple regression were performed to analyze the data. Results depicted that female sample students reported higher level of cognitive test anxiety in comparison to their male counterparts. Results also suggested a small but significant negative effect of cognitive test anxiety on students’ examination performance and that student cognitive test anxiety component accounted for 10% of variance in their examination performance. Results further revealed that the magnitude of relationship between students’ cognitive test anxiety and examination total point scores do not change much for the moderating variables and these variables accounted only for 3% of variance. The magnitude of moderating effect, however, found to be somewhat stronger in the school sector in comparison to students’ gender.

Early migration of a medially stabilized total knee arthroplasty

Aims Medial pivot (MP) total knee arthroplasties (TKAs) were designed to mimic native knee kinematics with their deep medial congruent fitting of the tibia to the femur almost like a ball-on-socket, and a flat lateral part. GMK Sphere is a novel MP implant. Our primary aim was to study the migration pattern of the tibial tray of this TKA. Methods A total of 31 patients were recruited to this single-group radiostereometric analysis (RSA) study and received a medial pivot GMK Sphere TKA. The distributions of male patients versus female patients and right versus left knees were 21:10 and 17:14, respectively. Mean BMI was 29 kg/m2 (95% confidence interval (CI) 27 to 30) and mean age at surgery was 63 years (95% CI 61 to 66). Maximum total point motions (MTPMs), medial, proximal, and anterior translations and transversal, internal, and varus rotations were calculated at three, 12, and 24 months. Patient-reported outcome measure data were also retrieved. Results MTPMs at three, 12, and 24 months were 1.0 mm (95% CI 0.8 to 1.2), 1.3 mm (95% CI 0.9 to 1.7), and 1.4 mm (0.8 to 2.0), respectively. The Forgotten Joint Score was 79 (95% CI 39 to 95) and Knee Injury and Osteoarthritis Outcome Score obtained at two years was 94 (95% CI 81 to 100), 86 (95% CI 75 to 93), 94 (95% CI 88 to 100), 69 (95% CI 48 to 88), and 81 (95% CI59 to 100) for Pain, Symptoms, Activities of Daily Living, Sport & Recreation, and Quality of Life, respectively. Conclusion In conclusion, we found that the mean increase in MTPM was lower than 0.2 mm between 12 and 24 months and thus apparently stable. Yet the GMK Sphere had higher migration at one and two years than anticipated. Based on current RSA data, we therefore cannot conclude on the long-term performance of the implant, pending further assessment. Cite this article: Bone Jt Open 2021;2(9):737–744.

How Many Total Points Should Your Course Have?

Background Instructors often use a point-based system for grading students (e.g., 100 or 1000 total points). This system can impact student outcomes. Objective The purpose of this research was to examine the implications of different point value courses for student emotions, perceptions of courses, and classroom performance. Method The lab-based study used an experimental design to gather student responses to a hypothetical course with one of three potential total point values (100, 1,000, or 100,000 points). The classroom-based study examined student responses to different point values in 12 actual courses in which students were enrolled (with either 100 or 1000 total points). Results In the lab-based study, courses with greater total point values (i.e., 1000 and 100,000) had greater emotional impact than a course with 100 total points. Participants in these conditions also preferred a course that featured a pass/fail scheme. In the classroom-based study, students in the 100-point condition (vs. 1000-point condition) missed more assignments, and as a consequence, performed more poorly in their course. Conclusion Higher total point values in courses may have a more significant impact on students’ emotions, and as a consequence, they may miss less work, and perform better in the course overall.

Maximum Total Point Motion of Five Points Versus All Points in Assessing Tibial Baseplate Stability

Maximum total point motion (MTPM), the point on a baseplate that migrates the most, has been used to assess the risk of tibial baseplate loosening using radiostereometric analysis (RSA). Two methods for determining MTPM for model-based RSA are to use either 5 points distributed around the perimeter of the baseplate or to use all points on the 3D model. The objectives were to quantify the mean difference in MTPM using 5 points vs. all points, compute the percent error relative to the 6-month stability limit for groups of patients, and to determine the dependency of differences in MTPM on baseplate size and shape. A dataset of 10,000 migration values was generated using the mean and standard deviation of migration in six degrees of freedom at 6 months from an RSA study. The dataset was used to simulate migration of 3D models (two baseplate shapes and two baseplate sizes) and calculate the difference in MTPM using 5 virtual points vs. all points and the percent error (i.e. difference in MTPM/stability limit) relative to the 6-month stability limit. The difference in MTPM was about 0.02 mm, or 4% percent relative to the 6-month stability limit, which is not clinically important. Furthermore, results were not affected by baseplate shape or size. Researchers can decide whether to use 5 points or all points when computing MTPM for model-based RSA. The authors recommend using 5 points to maintain consistency with marker-based RSA.

Intra-operative Clodronate Rinsing Improves the Integration of the Femoral Stem in a Prospective, Double-blinded, Randomized, Placebo-controlled Clinical RSA-study

Background: Periprosthetic bone loss after Total Hip Arthroplasty (THA), detected as an early migration of the prosthesis may predict later loosening of the implant. Objective: We hypothesized that intra-operative bisphosphonate rinsing would reduce bone resorption after THA. It might therefore be possible to achieve better early fixation of the implant. Methods: Nineteen patients suffering from arthrosis were recruited in a prospective, double-blinded, randomized, placebo-controlled clinical pilot trial. Patients were operated with an uncemented Bimetric stem using tantalum markers. The femoral proximal intramedullary canal was rinsed with 1mM clodronate in nine patients and with saline in 10 patients. These patients were followed for two years using radiostereometric analysis (RSA), dual energy x-ray absorptiometry (DXA) and the Harris Hip Score (HHS). Results: We did not found any significant differences between the study groups with regards to the primary output measures (maximum total point motion, MTPM). However, there was evidence that clodronate could affect periprosthetic bone quality; a beneficial effect in BMD in Gruen zone 3 during the two-year follow-up was observed, BMD decreased less in the clodronate group (p = 0.02). The maximal x-translation of the stem at 3-24 months was significantly two-fold, being higher in the placebo group (p = 0.02). The baseline BMD and the maximal total point motion (MTPM) at 3-24 months showed a positive correlation in the clodronate group and a negative correlation in the placebo group. Conclusion: In conclusion, further studies with larger patient groups and longer follow-up periods are needed to estimate the clinical importance of these findings and further to prove if an intraoperative clodronate rinsing prior to application of femoral stem during THA can prevent periprosthetic bone loss. Clinical Trial Registration No.: NCT03803839

Transient methane emissions in the Permian Basin

<p>The Permian Basin is the largest and fastest growing oil and gas (O&G) producing region in the United States. Methane (CH4), a powerful greenhouse gas, is emitted from both routine and abnormal or avoidable operating conditions in the Permian Basin, including O&G production, distribution, and processing. The time scales over which these emissions persist is uncertain, and this uncertainty can lead to large discrepancies in bottom-up emission accounting. Here, we conducted an extensive airborne campaign across the majority (55,000 km<sup>2</sup>) of the Permian Basin with imaging spectrometers to quantify individual CH4 point sources at the facility scale. We revisited each source multiple times and found that CH4 sources exhibited 26% persistence on average. Persistence-averaged CH4 emissions follow a heavy-tailed distribution, with 20% of facilities constituting 60% of the total point source budget. We quantified the total CH4 flux in the region (point + area sources) through an inverse analysis with satellite observations, and find that point sources make up 50% of the regional CH4 budget. Sector attribution of plumes shows that 50% of detected emissions result from O&G production, 38% from gathering, and 12% from processing plants. Imaging spectroscopy allows for identification of flares, and we find that 12% of CH4 plume emissions were associated with either active or inactive flares, and often emitting above 1000 kg CH4 h<sup>-1</sup>, even under active flaring. These results show that regular plume-scale monitoring in heterogeneous O&G basins is necessary to understand the high intermittency of operations and resulting emissions.</p>

Concepts et réalités du cinéma 360°

Although creating and displaying 360° environment animated images can be dated to the origins of cinema, audiovisual industry in the broadest sense of the term, has never been as interested by it as today. With or without headphones, the main problem with such media is no longer reception, distribution or production, but perhaps an adapted content. Creators have new constraints imposed by 360º such as, frame pseudo-liberation, managing to focus spectator attention on the central narrative or filming and hiding a crew when filming with a total point of view.In this paper we will explore some of these challenges. Firstly, we will try to understand narrative mechanisms and technological constraints of 360° medium analysing a few selected productions. Secondly, we will present some personal work where issues related to writing, aesthetics, production, post-production and distribution will be explained.To conclude, is important to explain why 360° audiovisual does not offer a real formal innovation but rather invites us to rediscover cinema and its concepts.