Accurately detecting active objects undergoing state changes is essential for comprehending human interactions and facilitating decision-making. The existing methods for active object detection (AOD) primarily rely on visual appearance of the objects within input, such as changes in size, shape and relationship with hands. However, these visual changes can be subtle, posing challenges, particularly in scenarios with multiple distracting no-change instances of the same category. We observe that the state changes are often the result of an interaction being performed upon the object, thus propose to use informed priors about object related plausible interactions (including semantics and visual appearance) to provide more reliable cues for AOD. Specifically, we propose a knowledge aggregation procedure to integrate the aforementioned informed priors into oracle queries within the teacher decoder, offering more object affordance commonsense to locate the active object. To streamline the inference process and reduce extra knowledge inputs, we propose a knowledge distillation approach that encourages the student decoder to mimic the detection capabilities of the teacher decoder using the oracle query by replicating its predictions and attention. Our proposed framework achieves state-of-the-art performance on four datasets, namely Ego4D, Epic-Kitchens, MECCANO, and 100DOH, which demonstrates the effectiveness of our approach in improving AOD. The code and models are available at https://github.com/idejie/KAD.git.

No abstract

ObjectiveThe optimal surgical intervention on the treatment for proximal humeral fractures (PHFs) remains uncertain. The aim of this study was to evaluate clinical outcomes following fixation of PHFs by intramedullary nails or locking platesMethodsThe Cochrane Library, PubMed, EMBASE, China Knowledge Resource Integrated (CNKI), Chongqing VIP and Wanfang databases were systematically searched for studies published between January 01, 1996 and December 31, 2016 that investigated intramedullary nail vs. locking plate in the surgical treatment of PHFs. A meta-analysis examined incision length, blood loss, operation time, fracture healing time, Constant scores and post-operative complications. The methodological and evidence quality were also assessed by MINORS and GRADE system.ResultsFrom the original 1024 references, 20 studies involving 1384 patients met the eligibility criteria. Analyses showed that intramedullary nails were superior to locking plates in incision length, peri-operative bleeding time, operation time and fracture healing time. However, there were no differences between treatments in Constant score or post-operative complications.ConclusionAlthough the evidence quality was poor, the results suggest that compared with locking plates, intramedullary nails may be a better choice for the repair of PHFs.

Background. The biomechanical effect of two implants, namely, proximal femoral nail antirotation for Asia (PFNA-II) and Expert Asian Femoral Nail (A2FN), for treating subtrochanteric fracture during healing stages, is still unclear. Methods. A 3D finite element model of an intact femur was constructed and validated. The fractured and postoperative models were accordingly produced. The postoperative models were loaded with the peak joint forces during gait for the soft and hard callus stages. The effects of stress distribution on the implants, femoral head and callus, and the deformation of the proximal femur were examined. Results. Both implants showed similar biomechanical effect in two healing stages. As the healing duration increased, the von Mises stress of two implants and the tensile stress of the femoral head decreased, whereas the compressive stress of the femoral head increased. However, the PFNA-II operation resulted in higher stress on the implant, lower stress on the proximal femur, and lower compressive stress and higher tensile stress on the callus than A2FN operation. Conclusions. The A2FN implant may provide a biomechanically superior construct for subtrochanteric fracture healing. However, the upper screw of the A2FN implant may be more likely to be loose in the healing process.

This study aimed to compare the fixation stability of a new device (SCCAB) for femoral neck fractures and the cancellous lag screws. Standardized femoral neck osteotomies were created in seven pairs of cadaver femurs and stabilized with either SCCAB or cancellous lag screws. The specimens were subjected to incremental axial loading to 1300 N and cyclic loading at 1300 N for 104 cycles. No significant differences in downward femoral head displacement, change in the superior osteotomy gapping, and load to failure were observed between the two groups. SCCAB may be potentially useful to treat femoral neck fractures.