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Local events are characterized by “where”, “when” and “what”. Just as (bosonic) spacetime forms the backdrop for location and time, (fermionic) property space can serve as the backdrop for the attributes of a system. With such a scenario I shall describe a scheme that is capable of unifying gravitation and the other forces of nature. The generalized metric contains the curvature of spacetime and property separately, with the gauge fields linking the bosonic and fermionic arenas. The super-Ricci scalar can then automatically yield the spacetime Lagrangian of gravitation and the Standard Model (plus a cosmological constant) upon integration over property coordinates.

In this paper, we observe that two-dimensional 0-surgery occurs in natural processes, such as tornado formation and other phenomena reminiscent of hole drilling. Inspired by such phenomena, we introduce new theoretical concepts which enhance the formal definition of two-dimensional 0-surgery with the observed dynamics. To do this, we first present a schematic model which extends the formal definition to a continuous process caused by local forces. Next, for modeling phenomena which do not happen on surfaces but are three-dimensional, we fill the interior space by defining the notion of solid two-dimensional 0-surgery. Finally, we connect these new theoretical concepts with a dynamical system and present it as a model for both two-dimensional 0-surgery and natural phenomena exhibiting it. We hope that through this study, topology and dynamics of many natural phenomena will be better understood.

Bone grinding is a craniotomy procedure which is used to remove a bone flap from the skull to expose and create an access for the dissection of tumors. In this study, a computer-controlled neurosurgical bone grinding has been used to explore the effect of various neurosurgical bone grinding parameters, such as cutting forces, torque, grinding force ratio, and temperature generated during bone grinding have been investigated. Bone samples after grinding have been assessed for morphological analysis. Based on the outcomes, a multi-attribute decision-making methodology based on grey relational analysis has been adopted. Regression models have been developed and then validated to ensure the adequacy of the developed models. Subsequently, a comparative analysis of experimental and predicted results have been presented. It is revealed that grinding forces and torque decreased with the escalation of rotational speed from 35,000 revolutions per minute (rpm) to 55,000rpm. The optimum combination of process parameters found as rotational speed of 55,000rpm, feed rate of 20mm/min, and depth of cut of 0.50mm.

The sagittal plane, which Pauwels regarded as being of no importance for the hip, was studied in the whole body with respect to posture while walking. After a preliminary study, which confirmed the importance of the sagittal plane for the hip, we performed a 3-dimensional modelling of the hip using the finite element method, with the aim of studying the resultant force exerted at the centre of the coxofemoral joint and of analysing the actions of the muscles from the efforts recorded. On the basis of these findings, we represented the overall mechanical problem of the hip in schematic terms as a variable dynamic balance. The results of this work also allowed us to establish in detail the impact of optimisation on the muscular actions and the impact of variations in displacement and the acceleration of the partial centre of gravity on the results recorded. Finally, the isolated hip model was developed, with the aims of allowing us to study the relations existing between variations in the angle of femoral anteversion and variations in forces, and of making a contribution to anthropological studies of the structures of locomotion through the ages.

The lack of awareness of the exact number of instantaneous centers of knee flexion/extension rotation leads to the presence in the market of total knee arthroplasty (TKA) femoral components designed under different hypotheses. Although single radius (SR) designs are thought to replicate the physiological behavior in a more realistic way, surgeons do not always agree about the veracity of their theoretical advantages with respect to the multiple radii components (J-curve (JC) design). Apart from clinical studies, up to now, any literature study biomechanically and exhaustively compares these two TKA solutions, thus a finite element analysis (FEA) has been carried out. In particular, two models were defined to analyze the performance of a SR design and a JC design with the same tibial component during gait cycle and squat motor task. Tibio-femoral kinematics and kinetics have been investigated comparing the resulting contact area between components, internal–external (IE) rotation, position and magnitude of the center of total forces due to contact pressure and polyethylene von Misses stresses. Results demonstrate that, for low demanding tasks, there are no significant differences between the two designs, however, during the squat motor task, some changes in contact force and increases in polyethylene stress were identified for the SR solution.

Local events are characterized by “where”, “when” and “what”. Just as (bosonic) spacetime forms the backdrop for location and time, (fermionic) property space can serve as the backdrop for the attributes of a system. With such a scenario I shall describe a scheme that is capable of unifying gravitation and the other forces of nature. The generalized metric contains the curvature of spacetime and property separately, with the gauge fields linking the bosonic and fermionic arenas. The super-Ricci scalar can then automatically yield the spacetime Lagrangian of gravitation and the Standard Model (plus a cosmological constant) upon integration over property coordinates.

Bone grinding is a craniotomy procedure which is used to remove a bone flap from the skull to expose and create an access for the dissection of tumors. In this study, a computer-controlled neurosurgical bone grinding has been used to explore the effect of various neurosurgical bone grinding parameters, such as cutting forces, torque, grinding force ratio, and temperature generated during bone grinding have been investigated. Bone samples after grinding have been assessed for morphological analysis. Based on the outcomes, a multi-attribute decision-making methodology based on grey relational analysis has been adopted. Regression models have been developed and then validated to ensure the adequacy of the developed models. Subsequently, a comparative analysis of experimental and predicted results have been presented. It is revealed that grinding forces and torque decreased with the escalation of rotational speed from 35,000 revolutions per minute (rpm) to 55,000 rpm. The optimum combination of process parameters found as rotational speed of 55,000 rpm, feed rate of 20mm/min, and depth of cut of 0.50 mm.