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When flexible manipulators complete their movements to the desired position, vibrations occur at the endpoint. Reducing vibrations is an important advantage for eliminating positioning errors and monitoring position accuracy. However, the increase in vibration amplitudes leads to the inability to complete the planned tasks in the applications and results in loss of productivity. Therefore, the reduction of end-effector vibrations is an important research area. In this study, a motion-based control (MBC) method with designed motion profiles is introduced to reduce the endpoint vibrations of epoxy–glass-reinforced composite manipulators. Three different motion profiles, namely Modification-1, Modification-2, and Modification-3, are designed according to time and maximum velocity values depending on the system's frequencies. For the design of Modification-1, variable deceleration and acceleration times are considered, while for Modification-2 and Modification-3, both the maximum angular velocity and the deceleration and acceleration times are utilized. For two different angular positions and motion times, all motion profiles are applied to two composite manipulators with different frequencies, and the results are experimentally and numerically obtained to examine the vibration performance of MBC. Simulation results confirmed with experiments are achieved using mathematical models in ANSYS. To evaluate the effectiveness of MBC, the change in RMS values of endpoint vibration responses and the reduction rates are presented comparatively for all motion profiles. The results show significant advantages for the MBC method, reducing vibrations by approximately 99%, and eliminating positioning errors caused by vibrations.

A novel approach in evaluating the conformance test costs of deterministic finite-state machines (FSMs) was developed in an effort to address the weaknesses of conventional communication protocols. The dual-state graph augmentation technique, which dwells on the use of unique input/output (UIO), functions as a Chinese postman optimization problem. By taking account of all possible UIO sequences, the technique has been proven to yield minimum length UIO sequences, thereby minimizing conformance test costs.

The aim of this study was to evaluate the analgesic efficacy of two different intraarticular injections; morphine and/or neostigmine. Sixty patients scheduled for arthroscopic knee surgery under general anesthesia were randomly allocated into four groups at the end of the surgery to receive morphine 2 mg (Group M), neostigmine 500 [micro]g (Group N), morphine 2 mg and neostigmine 500 [micro]g (Group MN) and 20 mL saline (Group S) intraarticularly. Visual analog scale (VAS) scores, analgesic consumption and side effects through 24 hours were recorded postoperatively. VAS scores were lower in the first three groups, while total analgesic consumption was significantly lower in Group M (p< 0.05). Side effects did not differ between the groups. Although intraarticular neostigmine provided pain control and diminished analgesic use compared to placebo, the combination of neostigmine and morphine did not result in a comparable postoperative pain score and analgesic use with morphine alone. Keywords: Pain | intraarticular | morphine | neostigmine, Table of Contents Introduction Results Discussion and Conclusions Address to correspondence to Introduction Intraarticular drug administration is a popular technique for postoperative analgesia after arthroscopic knee surgery (1). Although local [...]

We aimed to compare the effects of lidocaine and adrenaline with ibuprofen syrup (administered before adenotonsillectomy) on post-operative analgesia and initiation of oral feeding. One group of 20 children received 100 g/5 ml ibuprofen suspension (10 mg/kg) 1 h before anaesthesia; bleeding control was provided by pre-incisional administration of 1:200000 adrenaline solution (10 ml). The same amount of 0.5% lidocaine solution plus 1:200000 adrenaline was applied pre-incisionally in a similar manner in a second group of 20 children. No significant differences were observed between the two groups in terms of the duration of operation and anaesthesia, post-operative pain scores, paracetamol requirements, times to initiation of liquid and solid food intake, or adverse side-effects. We conclude that ibuprofen syrup applied pre-incisionally and local infiltration with lidocaine are equally effective for post-operative analgesia.

In this paper, we introduce a personalized parameterization approach, namely prep-g, to explore impact of gene expression values from breast cancer patients on tumor growth and shrinkage characteristics using xenograft models. In construction of prep-gparameterization, in addition to individual effects of the breast cancer-related gene expressions, the impact of the correlation among them and the contribution of their multiple orders are considered. Tumor growth behavior, and delay and shrinkage effects of anti-cancer agents are examined in six case studies using xenograft models implanted with breast cancer cell lines. Tumor growth parameters for er+cell lines bt-474and mcf-7, and drug-related shrinkage parameters for cell lines mda-mb-231, mda-mb-468and bt-474under the monotherapy of drugs paclitaxel and doxorubicin are computed. Consistency of the experimental data reported in several studies in literature for multiple breast cancer cell lines in mice models and the computed results from prep-gare encouraging, which indicates that construction of mathematical models for tumor growth and shrinkage by combining gene expressions and clinical information may be feasible.

The motion profiles defined to move the robot manipulators directly affect the endpoint position accuracy, position repeatability, and vibration control of the manipulators in engineering applications, especially in flexible manipulators. This study deals theoretically and experimentally with the dynamic performance of two different motion profiles in reducing the vibration amplitudes of a single-link flexible composite manipulator. Manipulator is produced from epoxy-glass composite material with a layer orientation of [0/90/0/0/90/0] lay-up. For theoretical studies, the SimMechanics-based flexible dynamic model is created using flexible beam block in MATLAB/Simulink, and the finite element model is established with a layered structural solid element in ANSYS. Two different motion profiles are defined to drive the manipulator for different stopping positions and motion times. Simulations are achieved by using motion profiles. The performance of the motion profiles is evaluated by considering the reduction ratio of residual displacement and acceleration vibrations generated at the endpoint of the manipulator. RMS values of residual vibrations are calculated to determine the rate of residual vibration suppression. Reduction ratios are determined by considering the maximum vibration amplitudes as the reference RMS value. The effectiveness of the motion profiles is presented in comparison with the reduction rates. Simulation results obtained using both displacement and acceleration vibration responses are verified with experiments for all motion cases. Also, the modeling and analysis of the composite manipulator are verified by simulations and experiments with the SimMechanics-based modeling method, and the reliability of the proposed method is increased.

The role and importance of information technology and computers cannot be ignored due to their extensive usages in different application areas. Along with easier access to the Internet and computers, education has become one of the foremost areas benefiting from this progress. Minimizing geographical barriers and facilitating knowledge sharing between people are some of the outcomes of this progress. Because of the advances in information technology, needs for minimizing geographical barriers and facilitating knowledge sharing, computer-supported collaborative learning (CSCL) has emerged. In this study, types of communication tools used by students to share their knowledge during their group projects were analyzed (excluding the e-mail service) in terms of preference. A survey containing questions about demographic information and preferences of communication tools used by students during their group projects was conducted to a reasonable number of students and results are presented in this study.

We introduce a genetic algorithm–based topology control mechanism, named 3D–GA, for Autonomous Underwater Vehicles (AUVs) operating in Underwater Sensor Networks (UWSNs). Using limited information collected from a node's local neighbours, 3D–GA runs autonomously at each AUV and provides guidance for its speed and direction towards a uniform spatial distribution while maintaining network connectivity. Imprecise and limited neighbourhood knowledge could potentially disrupt convergence towards a uniform and stable spatial coverage. We demonstrate that AUVs running our 3D–GA create a highly resilient network that can adapt to changing conditions such as the addition, loss or malfunction of number of AUVs. We also show that the ambiguity in detecting neighbours' exact locations does not prevent 3D–GA from achieving a uniform coverage but requiring AUVs travel longer distances to stabilise. Our simulation software results verify that 3D–GA is an effective tool for providing a robust solution for volumetric spatial control of AUVs in UWSNs.

We present genetic algorithms (GAs) as a decentralised topology control mechanism distributed among active running software agents to achieve a uniform spread of terrestrial unmanned vehicles (UVs) over an unknown geographical area. This problem becomes more challenging under the harsh and bandwidth limited conditions of military applications. Using only local neighbour information, a GA guides each UV to select a 'fitter' speed and direction among exponentially large number of choices, converging towards a uniform node distribution. In an observed occurrence of a threat situation during a mission where UVs are to spread uniformly over an unknown terrain, if the number of UVs change with time (e.g., losing assets due to hostile forces), the remaining units should reposition themselves to compensate the loss in area coverage. Our simulation software results show that GAs can be an effective tool for providing a robust solution for topology control of UVs in military applications.

Non-alcoholic fatty liver disease (NAFLD) is considered a risk factor for atherosclerosis. The aim of the present study was to investigate the association of the pulsatility index (PI) of basilar artery (BA) and carotid intima media thickness (IMT) in diabetic and non-diabetic NAFLD patients. We compared a group of 80 stroke-free, diabetic and non-diabetic NAFLD patients and a control group of 26 healthy subjects without NAFLD. We then evaluated the PI of the BA by transcranial Doppler ultrasonography, and carotid IMT. The PI was significantly higher in diabetic NAFLD patients than in controls (p<0.003). Carotid IMT and asymmetrical dimethylarginine (ADMA) levels were higher in NAFLD patients than controls respectively (p<0.003, p<0.04). The PI of the BA was significantly correlated with age (R=0.369, p<0.001), male gender (R=0.207, p=0.035). diabetes (R=0.332, p=0.001), carotid IMT (R=0.296, p=0.002) and ADMA (R=0.349, p=0.015). A multiple regression analysis was performed with PI as the dependent variable with known clinical risk factors. Age (β=3.54, p<0.001), diabetes (β=2.32, p=0.022), gender (β=2.20, p<0.03), ADMA (β=2.25, p<0.031), and carotid IMT (β=2.41, p<0.017), were independent predictive factors of BA PI. Adjustment for age and gender did not alter these relative risks, exhibiting a significant independent contribution to PI. The increased PI observed in this study represents enhanced cerebrovascular resistance, and we observed that the age, male gender, diabetes, ADMA levels, and carotid IMT were independent predictive factors of BA PI.

This study compared the analgesic efficacy of intrathecal (IT) morphine plus IV patient-controlled analgesia (PCA) morphine with IV PCA morphine alone in 33 patients undergoing thoracotomy randomized to two groups: the IT morphine group (n= 17) received 10 μg/kg morphine 1 h before the end of surgery, while the control group (n= 16) did not. All patients had access to an IV PCA pump post-operatively that delivered 2 mg morphine boluses. Post-operative pain and sedation scores, respiratory and haemodynamic parameters, and morphine demand and delivery were assessed up to 48 h. Post-operative pain scores and morphine consumption were significantly reduced, while peak expiratory flow rates were significantly increased in the IT morphine group compared with controls. We concluded that IT morphine in addition to IV PCA established superior analgesia and maintained better respiratory function compared with IV PCA alone in post-thoracotomy patients.

We compared the efficacy of preoperative intramuscular lornoxicam and ketoprofen for post-operative analgesia in patients undergoing abdominal hysterectomy. This randomized, double-blind, placebo-controlled, parallel-group study investigated 60 patients who received lornoxicam (group L, 8 mg), ketoprofen (group K, 100 mg) or saline (group C) 60 min before standard anaesthesia. All patients received patient-controlled analgesia (intravenous morphine) during the post-operative period. Visual analogue scale (VAS) scores recorded 2, 4, 6 and 12 h after surgery in groups L and K patients were significantly lower than in group C patients, and VAS scores at 2, 4 and 6 h in group L patients were significantly lower than those in group K patients. Morphine consumption in groups L and K was significantly lower than in group C. Pre-emptive administration of lornoxicam and ketoprofen effectively reduced post-operative pain and morphine consumption, and lornoxicam was more effective than ketoprofen in the early post-operative period.

We compared the oxygen cost of breathing between pressure-support ventilation (PSV) and airway pressure release ventilation (APRV). This prospective, randomized, crossover study was conducted in a mixed ICU of a university hospital. Twenty clinically stable and spontaneously breathing patients after long-term mechanical ventilation were included. The patients were randomized to start on either PSV or APRV mode and measurements were obtained after an adaptation period of 30 minutes with a PaCO2between 35–45 mmHg and PaO2above 60 mmHg. Patients were then switched to the other mode and the same measurements were repeated. Indirect calorimetry was performed during each ventilatory mode for a period of 30 minutes. Oxygen consumption, energy expenditure, CO2production, and respiratory quotient were measured. The parameters did not differ significantly between the two ventilatory modes, regardless of the patient's randomization. There were no statistically significant differences with regard to respiratory rate, minute volume, and blood gas analysis. All patients tolerated both ventilatory modes without signs of discomfort. PSV and APRV produced similar results in terms of oxygen cost of breathing and other metabolic variables.

Purpose Although significant decrease in retinal perfusion is usually not observed before all of the cervical arteries became markedly narrowed in patients with Takayasu's disease (TD), we present bilateral glaucomatous optic neuropathy in a patient with TD without any cervical arterial stenosis.Methods Ophthalmoscopic examination disclosed glaucomatous optic neuropathy in both eyes with 7/10-cup/disc ratio in the right eye and 9/10 in the left eye. Left subclavian selective arteriographic examination demonstrated segmental high-grade stenosis, namely 90 percent stenosis in the mid portion of the left subclavian artery. Arteriography, digital subtraction angiography (DSA), magnetic resonance angiography (MRA) and color Doppler sonography revealed patent cervical, carotid interna, ophthalmic, retinal and posterior ciliary arteries.Results Patient was followed up for 48 months with frequent intervals and there was no deterioration of visual acuity, visual field and optic neuropathy without any antiglaucomatous treatment.Conclusions Although it is a known fact that classical ophthalmic manifestations of the TD occur only when major cervical arteries are occluded, no occlusion was observed in this patient with bilateral optic atrophy. The optic nerve damage is caused by various factors, but these factors require much elucidation before the optic neuropathy can be understood.

We compared the time‐course of action of vecuronium in 16 burned children undergoing excision and autograft surgery with that of ten unburned children. Standardized anaesthesia was induced with thiopentone 4–6 mg kg−1and fentanyl 1 μg??kg−1and maintained with endtidal 1–1.5% isoflurane in N2O/O2. Neuromuscular responses were monitored by acceleromyography (TOF‐Guard, Organon Teknika/Biometer) with supramaximal train‐of‐four (TOF) stimuli delivered every 15 s. Vecuronium 0.1 mg kg−1was administered intravenously. Onset was recorded as the time, in seconds, between the initial bolus of vecuronium and a decline in the first twitch of TOF (T1) to 5% of control. The times for the recovery of T1–25%, 50% and 75% of control, recovery index and the recovery of TOF 25% and 50% were recorded. Onset of action was found slower in burned patients (189??70 s) than in control (98??20 s) (P< 0.01). Recovery times of T125, T150, T175, TOF25and TOF50were significantly shorter in burned patients indicative of decreased sensitivity to vecuronium (P< 0.01).

Reports of complications associated with local anesthesia in ophthalmic surgery have increased conspicuously in recent years. Sub-Tenon's capsule anesthesia for anterior segment surgery avoids the risks of retrobulbar and peribulbar injections. This study compared sub-Tenon's and retrobulbar anesthesia. Patients undergoing various anterior segment surgery were randomly assigned to sub-Tenon's or retrobulbar anesthesia; 300 were operated with 1-quadrant sub-Tenon's anesthesia (1-QST) and the results were compared with 270 patients operated with retrobulbar anesthesia.Retrobulbar anesthesia consisted of a 2.5 ml injection of a 1: 1 mixture of 2% lidocaine without epinephrine and 0.5% bupivacaine. Sub-Tenon's anesthesia involved direct transconjunctival infiltration of the same local anesthetic directly into the sub-Tenon's space, in the inferior-nasal quadrant, using a blunt 23-gauge cannula. Patients undergoing various anterior segment surgery procedures were randomly assigned to 1-QST or retrobulbar anesthesia; 300 patients were operated with 1-QST and the results were compared with 270 patients operated with retrobulbar anesthesia.Preinjection mean (±SD) IOP were 12.9±3.7 mmHg in the retrobulbar and 13.4±3.2 mmHg in the 1-QST patients. Preoperative intraocular pressures were 8.7±3.0 mmHg in the retrobulbar and 9.2±3.2 mmHg in 1-QST patients. Pre- and postinjection IOP for retrobulbar and 1-QST patients were similar.Pain scores for delivery of the anesthetic, using a numerical rating scale, produced a median score of 1 for 1-QST and 2 for the retrobulbar technique. For the subsequent operative procedure, the median score was 1 for 1-QST and 2 for the retrobulbar patients. Complete akinesia was achieved in 41% with 1-QST and in 69% of retrobulbar patients. 1-QST patients with incomplete akinesia most often had lateral muscle function which did not interfere with the operation.We found the use of a blunt cannula to deliver anesthetic into the sub-Tenon's space as a simple, safe and effective alternative approach to traditional retrobulbar anesthesia in anterior segment surgery.

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