Unstable intertrochanteric fractures: How to prevent uncontrolled impaction and shortening of the femur

Background/Aim. Unstable intertrochanteric (IT) fractures, especially fractures with a reverse or transverse fracture line, have tendencies to make significant impaction on shortening of the femoral neck and lower extremity. The biomechanical complexity of the fracture, the type and the position of the implant are known to influence postoperative outcome. The aim of this study was to compare characteristics of two versions of dynamic hip implants in controlling the dynamization of unstable IT fractures of the femur. Methods. In the prospective study that included 1,115 patients with fractures of the proximal femur, 61 patients had IT fractures with a reverse or transverse fracture line. All the patients were treated surgically with the same implant in two versions: Dynamic Hip Screw - DHS-MB-S implant with a rigid part of standard length (40 mm) and DHS-MB-I implant, with a rigid part of the implant individualized for each patient depending on the transverse diameter of the proximal femur. The patients were under gradual radiographic and clinical control. Six months postoperatively we measured the length of the extremity and the degree of the medialization of the distal part of the femur. Results. All the fractures healed six months after the operation. Medialization and shortening of the extremity were significantly less in the group with fractures fixed by the DHSMB-I implant, in which length of the rigid part of the implant was preoperatively measured individually for each patient. Conclusion. In order to achieve a desired functional result, the control of dynamisation in unstable IT fractures is significant in the fixation of these fractures of the femur. We presented possible methods to realize it by the contact of the rigid part of our implant with medial cortex of the proximal fragment of the femur

A software system for teaching and commanding the industrial robots

Design features of a software system for programming industrial robots with dynamic control are described. The software is intended for implementation an a microprocessor-based system and should enable the user to control a robot via specialized programming language RL. The paper contains description of the RL language and description of the system structure. Main characteristics and advantages of the system as well as questions concerning its realization on existing microprocessors are also discussed

Free vibration of structures composed of rigid bodies and elastic beam segments

Free vibration of structures composed of rigid bodies and elastic beam segments is considered, assuming that the mass centers of rigid bodies are not located on the neutral axes of undeformed elastic beam segments. It is assumed that the rigid bodies of the system perform planar motion in the same plane and that their mass centers are located in that plane. The elastic beam segments are treated as the Euler-Bernoulli beams. In order to determine natural frequencies of the system, modification of the conventional continuous-mass transfer matrix method has been clone. The order of the overall transfer matrix has been reduced by this modification. Theoretical considerations are accompanied by two numerical examples.This is the peer reviewed version of the article: Obradović, A.; Šalinić, S.; Trifković, D.; Zorić, N.; Stokić, Z. Free Vibration of Structures Composed of Rigid Bodies and Elastic Beam Segments. Journal of Sound and Vibration 2015, 347, 126–138. [https://doi.org/10.1016/j.jsv.2015.03.001

General-purpose controller for industrial manipulators

The general-purpose controller for industrial robots of arbitrary type is described. It enables control of robots powered by DC electromotors or hydraulic actuators. The controller includes programs for communication with operators, robot program language, program for on-line robot kinematics, and program for direct digital servosystems for tracking trajectories including on-line dynamics of the robot. The controller is implemented on two microcomputers based on INTEL 8086 microprocessors. All parts of the controller hardware and software are briefly described. Implementation of on-line kinematics and on-line dynamics and the choice of the control law are considered in more details

Free vibration of structures composed of rigid bodies and elastic beam segments

Free vibration of structures composed of rigid bodies and elastic beam segments is considered, assuming that the mass centers of rigid bodies are not located on the neutral axes of undeformed elastic beam segments. It is assumed that the rigid bodies of the system perform planar motion in the same plane and that their mass centers are located in that plane. The elastic beam segments are treated as the Euler-Bernoulli beams. In order to determine natural frequencies of the system, modification of the conventional continuous-mass transfer matrix method has been clone. The order of the overall transfer matrix has been reduced by this modification. Theoretical considerations are accompanied by two numerical examples.Peer reviewed version of the article: [https://machinery.mas.bg.ac.rs/handle/123456789/4330

Free vibration of structures composed of rigid bodies and elastic beam segments

Free vibration of structures composed of rigid bodies and elastic beam segments is considered, assuming that the mass centers of rigid bodies are not located on the neutral axes of undeformed elastic beam segments. It is assumed that the rigid bodies of the system perform planar motion in the same plane and that their mass centers are located in that plane. The elastic beam segments are treated as the Euler-Bernoulli beams. In order to determine natural frequencies of the system, modification of the conventional continuous-mass transfer matrix method has been clone. The order of the overall transfer matrix has been reduced by this modification. Theoretical considerations are accompanied by two numerical examples

Memory load effect in auditory-verbal short-term memory task: EEG fractal and spectral analysis

The objective of this preliminary study was to quantify changes in complexity of EEG using fractal dimension (FD) alongside linear methods of spectral power, event-related spectral perturbations, coherence, and source localization of EEG generators for theta (4-7 Hz), alpha (8-12 Hz), and beta (13-23 Hz) frequency bands due to a memory load effect in an auditory-verbal short-term memory (AVSTM) task for words. We examined 20 healthy individuals using the Sternberg's paradigm with increasing memory load (three, five, and seven words). The stimuli were four-letter words. Artifact-free 5-s EEG segments during retention period were analyzed. The most significant finding was the increase in FD with the increase in memory load in temporal regions T3 and T4, and in parietal region Pz, while decrease in FD with increase in memory load was registered in frontal midline region Fz. Results point to increase in frontal midline (Fz) theta spectral power, decrease in alpha spectral power in parietal region-Pz, and increase in beta spectral power in T3 and T4 region with increase in memory load. Decrease in theta coherence within right hemisphere due to memory load was obtained. Alpha coherence increased in posterior regions with anterior decrease. Beta coherence increased in fronto-temporal regions. Source localization delineated theta activity increase in frontal midline region, alpha decrease in superior parietal region, and beta increase in superior temporal gyrus with increase in memory load. In conclusion, FD as a nonlinear measure may serve as a sensitive index for quantifying dynamical changes in EEG signals during AVSTM tasks

Parazitska fauna svinja u organskom držanju

Parasites infection were permanent health problem at swine production at exensive and farm breeding. Organic breeding induced permanent contact of swine and intermeditae host of numerous parasites and those infection were more frequent at these breeding condition. In most cases there were presented biohelminths from genus Metastrongylus, nematode which cause gastritis verminosa (Ascarops strongyllinae, Physocephalus sexalatus and Hyostrongylus rubidus), Oesophagostomum spp. And Macracanthorhynchus hirudinaceus. There were presented at lover rate of infection Acaris suum,. and other helminths.Parazitske infekcije predstavljaju stalne pratioce svinjarske proizvodnje, nezavisno od načina držanja. Organska proizvodnja i držanje uslovljavaju da svinje imaju direktan dodir sa mnoštvom prelaznih domaćina parazita a samim tim da su kod njih parazitske infekcije češće. U najvećoj meri ovde se javljaju biohelminti od kojih su najvažniji predstavnici roda Metastrongylus, uzročnici verminoznog gastrita (Ascarops strongyllinae, Physocephalus sexalatus and Hyostrongylus rubidus), Oesophagostomum spp. i Macracanthorhynchus hirudinaceus. Ovde se takođe javljaju i Acaris suum, i drugi helminti u manjem obimu

Somatotype characteristics of normal-weight and obese women among different metabolic subtypes

ABSTRACT Background Obesity is a well known risk factor for the development of metabolic abnormalities. However, some obese people are healthy and on the other hand some people with normal weight have adverse metabolic profile, therefore it can be assumed that there is a difference in physical characteristics amongst these people. The aim of this study was to establish whether there are somatotype differences between metabolically healthy and metabolically obese women who are obese or of normal weight. Subjects and methods Study included 230 women aged 44.76 ± 11.21y. Metabolic status was assessed according to IDF criteria, while somatotype was obtained using Heath & Carter method. Results Significant somatotype differences were observed in the group of women with normal-weight: metabolically healthy women had significantly lower endomorphy, mesomorphy and higher ectomorphy compared to metabolically obese normal-weight women (5.84-3.97-2.21 vs. 8.69-6.47-0.65). Metabolically healthy obese women had lower values of endomorphy and mesomorphy and higher values of ectomorphy compared to ‘at risk’ obese women but the differences were not statistically significant (7.59-5.76-0.63 vs. 8.51-6.58-0.5). Ectomorphy was shown as an important determinant of the favorable metabolic profile (cutoff point was 0.80). Conclusion We concluded that, in addition to fat mass, metabolic profile could be predicted by the structure of lean body mass, and in particular by body linearity