Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Context: Sit-to-stand tasks are commonly facilitated by modifying the initial position of the center of mass relative to the feet. It was hypothesized that modifications in the center of mass trajectory during sit-to-stand tasks altered the total body momentum at seat departure and redistributed the lower extremity net joint moments.', 'Between-task within-subject comparison was employed using a robust statistical method to accommodate for small sample size.', 'Six individuals performed four sit-to-stand tasks with systematic modifications in the initial center of mass position by varying the orientation of the lower extremity segments. The momentum of the center of mass and lower extremity net joint moments were quantified and compared.', 'Reducing the horizontal center of mass displacement significantly reduced horizontal total body momentum required at seat departure. Sit-to-stand tasks initiated with more horizontal shank and thigh positions required significantly greater knee and hip extensor net joint moments than those with more vertical shank and thigh positions. Sit-to-stand tasks initiated with vertical shank positions also required significantly greater hip extensor net joint moments as compared to those with more horizontal shank orientations.
Answer: When changes in initial center of mass position are made, alteration in center of mass horizontal momentum and the orientation of the lower extremity segments relative to the reaction force are observed. Consequently, mechanical demand imposed on the ankle, knee, and hip joint is redistributed. The magnitude of the net joint moments is dependent on the segment orientation, the reaction force, and the adjacent net joint moment.
Does modifying center of mass trajectory during sit-to-stand tasks redistribute the mechanical demand across the lower extremity joints?

Context: The aim of this study was to evaluate how closely analysis of bone quality performed using the bone mineral density (BMD) values obtained by quantitative computerized tomography (QCT) reflected the histologic bone density.', "Eighteen patients requiring implant therapy underwent CT scanning. Their data were processed using Image Master software, and the BMD was calculated by measuring the Hounsfield units and relating those values to a phantom (Calibration Phantom, Quantitative Technologies). Each patient wore a radiographic-surgical template in which titanium cylinders were placed as a drilling guide for preparation of the implant site. The mouth regions where the titanium guides were placed (on the CT images and in the patient's mouth) corresponded to the implant sites where the BMD was measured and where tissue specimens for histomorphometric analysis retrieved. Forty specimens measuring 6 mm in length and 2 mm in diameter were obtained. Histomorphometric analysis was performed by digitizing the images, which were subsequently analyzed using the image analysis software IAS 2000. The bone volume (BV) was calculated as a percentage by dividing the area occupied by the mineralized bone over the entire microscopic field.", 'The results of the statistical analysis showed a Pearson correlation coefficient of 0.691 between the BV and BMD values, with a P value < 0.01, which was considered significant.
Answer: The results of this study support the use of QCT to assess the bone quality before implant placement to improve the planning of implant treatment.
Are bone mineral density and bone histomorphometry statistically related?

Context: To avoid adverse patient outcomes from inappropriate treatment, it is recommended that an atrial electrogram (AEG) be recorded whenever atrial arrhythmias develop in patients after cardiac surgery. However, AEGs are not commonly performed because nurses lack knowledge about differentiating atrial rhythms on AEGs.', "To investigate whether completing a novel online evidence-based education program on interpreting AEGs would improve critical care nurses' AEG interpretation.", 'Specialized critical care nurses were taught about obtaining and interpreting atrial rhythms on AEGs using a 42-minute online mini-movie. AEG interpretation was assessed pre and two and eight weeks post-intervention.', 'AEG interpretation increased two weeks post intervention and was retained at eight weeks. Some participants used this newly acquired knowledge to interpret arrhythmias that were not taught during the education program.
Answer: Accurate interpretation of AEGs is an easy skill for specialized critical care nurses to learn via an online education program.

Does atrial electrogram interpretation improve after an innovative education program?