939 resultados para Effects evaluation


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The present study was conducted to determine the effects of different variables on the perception of vehicle speeds in a driving simulator. The motivations of the study include validation of the Michigan Technological University Human Factors and Systems Lab driving simulator, obtaining a better understanding of what influences speed perception in a virtual environment, and how to improve speed perception in future simulations involving driver performance measures. Using a fixed base driving simulator, two experiments were conducted, the first to evaluate the effects of subject gender, roadway orientation, field of view, barriers along the roadway, opposing traffic speed, and subject speed judgment strategies on speed estimation, and the second to evaluate all of these variables as well as feedback training through use of the speedometer during a practice run. A mixed procedure model (mixed model ANOVA) in SAS® 9.2 was used to determine the significance of these variables in relation to subject speed estimates, as there were both between and within subject variables analyzed. It was found that subject gender, roadway orientation, feedback training, and the type of judgment strategy all significantly affect speed perception. By using curved roadways, feedback training, and speed judgment strategies including road lines, speed limit experience, and feedback training, speed perception in a driving simulator was found to be significantly improved.

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The complexity and challenge created by asphalt material motivates researchers and engineers to investigate the behavior of this material to develop a better understanding, and improve the performance of asphalt pavement. Over decades, a wide range of modification at macro, meso, micro and nano scales have been conducted to improve the performance of asphalt pavement. This study was initiated to utilize the newly developed asphalt modifier pellets. These pellets consisted of different combinations of calcium carbonate (CaCO3), linear low-density polyethylene (LLDPE) and titanate coupling agent (CA) to improve the asphalt binder as well as pavement performance across a wide range of temperature and loading pace. These materials were used due to their unique characteristics and promising findings from various industries, especially as modifiers in pavement material. The challenge is to make sure the CaCO3 disperses very well in the mixture. The rheological properties of neat asphalt binder PG58-28 and modified asphalt binder (PG58-28/LLDPE, PG58-28/CaCO3, PG58-28/CaCO3/LLDPE, and PG58-28/CaCO3/LLDPE/CA), were determined using rotational viscometer (RV) test, dynamic shear rheometer (DSR) test and bending beam rheometer test. In the DSR test, the specimens were evaluated using frequency sweep and multiple shear creep recovery (MSCR). The asphalt mixtures (aggregate/PG58-28, aggregate/ PG58-28/LLDPE, aggregate/PG58-28/CaCO3, aggregate/PG58-28/LLDPE/CaCO3 and aggregate/PG58-28/LLDPE/CaCO3/CA) were evaluated using the four point beam fatigue test, the dynamic modulus (E*) test, and tensile strength test (to determines tensile strength ratio, TSR). The RV test results show that all modified asphalt binders have a higher viscosity compared to the neat asphalt binder (PG58-28). Based on the Jnr results (using MSCR test), all the modified asphalt binders have a better resistance to rutting compared to the neat asphalt binder. A higher modifier contents have resulted in a better recovery percentage of asphalt binder (higher resistance to rutting), except the specimens prepared using PECC’s modified asphalt binder (PG58-28/CaCO3/LLDPE). The BBR test results show that all the modified asphalt binders have shown comparable performance in term of resistance to low temperature cracking, except the specimen prepared using the LLDPE modifier. Overall, 5 wt% LLDPE modified asphalt binder was found to be the best asphalt binder in terms of resistance to rutting. Meanwhile, 3 wt% PECC-1CA’s modified asphalt binder can be considered as the best (in terms of resistance to thermal cracking) with the lowest mean critical cracking temperature. The appearance of CaCO3 was found useful merely in improving the resistance to fatigue cracking of asphalt mixture. However, application of LLDPE has undermined the fatigue life of asphalt mixtures. Adding LLDPE and coupling agent throughout this study does not sufficiently help in terms of elastic behavior which essential to enhance the resistance to fatigue cracking. In contrast, application of LLDPE has increased the indirect tensile strength values and TSR of asphalt mixtures, indicates a better resistance to moisture damage. The usage of the coupling agent does not change the behavior of the asphalt mixture, which could be due to imbalance effects resulted by combination of LLDPE and CaCO3 in asphalt binder. Further investigations without incorporating CaCO3 should be conducted further. To investigate the feasibility of using LLDPE and coupling agent as modifiers in asphalt pavements, more research should be conducted on different percentages of LLDPE (less than 3 wt%), and at the higher and w wider range of coupling agent content, from 3 wt% to 7 wt% based on the polymer mass.

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OBJECTIVE: To investigate cytochrome P450 (CYP) enzymes involved in metabolism of racemic and S-ketamine in various species and to evaluate metabolic interactions of other analgesics with ketamine. SAMPLE POPULATION: Human, equine, and canine liver microsomes. PROCEDURES: An analgesic was concurrently incubated with luminogenic substrates specific for CYP 3A4 or CYP 2C9 and liver microsomes. The luminescence signal was detected and compared with the signal for negative control samples. Ketamine and norketamine enantiomers were determined by use of capillary electrophoresis. RESULTS: A concentration-dependent decrease in luminescence signal was detected for ibuprofen and diclofenac in the assay for CYP 2C9 in human and equine liver microsomes but not in the assay for CYP 3A4 and methadone or xylazine in any of the species. Coincubation of methadone or xylazine with ketamine resulted in a decrease in norketamine formation in equine and canine liver microsomes but not in human liver microsomes. In all species, norketamine formation was not affected by ibuprofen, but diclofenac reduced norketamine formation in human liver microsomes. A higher rate of metabolism was detected for S-ketamine in equine liver microsomes, compared with the rate for the S-enantiomer in the racemic mixture when incubated with any of the analgesics investigated. CONCLUSIONS AND CLINICAL RELEVANCE: Enzymes of the CYP 3A4 family and orthologs of CYP 2C9 were involved in ketamine metabolism in horses, dogs, and humans. Methadone and xylazine inhibited in vitro metabolism of ketamine. Therefore, higher concentrations and diminished clearance of ketamine may cause adverse effects when administered concurrently with other analgesics.

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PURPOSE: G protein-coupled receptor agonists are being used as radiolabeled vectors for in vivo localization and therapy of tumors. Recently, somatostatin-based antagonists were shown to be superior to agonists. Here, we compare the new [111In/68Ga]-labeled bombesin-based antagonist RM1 with the agonist [111In]-AMBA for targeting the gastrin-releasing peptide receptor (GRPR). EXPERIMENTAL DESIGN: IC50, Kd values, and antagonist potency were determined using PC-3 and HEK-GRPR cells. Biodistribution and imaging studies were done in nude mice transplanted with the PC-3 tumor. The antagonist potency was assessed by evaluating the effects on calcium release and on receptor internalization monitored by immunofluorescence microscopy. RESULTS: The IC50 value of [(nat)In]-RM1 was 14 +/- 3.4 nmol/L. [(nat/111)In]-RM1 was found to bind to the GRPR with a Kd of 8.5 +/- 2.7 nmol/L compared with a Kd of 0.6 +/- 0.3 nmol/L of [111In]-AMBA. A higher maximum number of binding site value was observed for [111In]-RM1 (2.4 +/- 0.2 nmol/L) compared with [111In]-AMBA (0.7 +/- 0.1 nmol/L). [(nat)Lu]-AMBA is a potent agonist in the immunofluorescence-based internalization assay, whereas [(nat)In]-RM1 is inactive alone but efficiently antagonizes the bombesin effect. These data are confirmed by the calcium release assay. The pharmacokinetics showed a superiority of the radioantagonist with regard to the high tumor uptake (13.4 +/- 0.8% IA/g versus 3.69 +/- 0.75% IA/g at 4 hours after injection. as well as to all tumor-to-normal tissue ratios. CONCLUSION: Despite their relatively low GRPR affinity, the antagonists [111In/68Ga]-RM1 showed superior targeting properties compared with [111In]-AMBA. As found for somatostatin receptor-targeting radiopeptides, GRP-based radioantagonists seem to be superior to radioagonists for in vivo imaging and potentially also for targeted radiotherapy of GRPR-positive tumors.

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The cytokine tumor-necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL) has been shown to preferentially induce apoptosis in cancer cells. A previous study of our group demonstrated that non-small cell lung cancer cell lines can be sensitized to Apo2L/TRAIL-induced apoptosis by chemotherapeutic agents. The aim of the present study was the evaluation of these results in a model of primary culture of non-small cell lung cancer.

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This study explores the effects of three different 2-dose varicella zoster virus (VZV) vaccination strategies in Switzerland. The EVITA model was used to assess clinical benefits and costs of strategies (1) vaccination of 11-15 year old adolescents with a negative or uncertain history for chickenpox, (2) universal vaccination of toddlers at age 1 to 2 years, and (3) strategy 2 plus catch-up vaccination of 11-15 year old susceptible adolescents. The cost-effectiveness analysis compares strategies 2 and 3 versus strategy 1 (current vaccination policy in Switzerland). Probabilities for clinical outcomes and medical resource utilization were derived from a real-world survey among Swiss pediatricians and general practitioners including 236 individuals with VZV infection, published information on varicella complications, and expert opinion. Costs of medical resource utilization represent official Swiss medical tariffs. The model predicts both universal childhood vaccination strategies to be more effective in reducing varicella disease burden compared to strategy 1. Economically, both universal childhood vaccination strategies with or without catch-up result in net savings from the societal perspective reflected by a benefit cost ratio (BCR) of 1.22 or 1.29, respectively. In contrast, the model predicts net costs from the payer perspective (BCR of 0.27 and 0.30, respectively). These economic findings are comparable to those reported from other similar evaluations. However, due to the recent recommendation for using a 2-dose varicella vaccination schedule, our economic results for Switzerland are somewhat less favorable than those for other country analyses in which a less expensive 1-dose vaccination regimen for toddlers has been studied.

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While navigation systems for cars are in widespread use, only recently, indoor navigation systems based on smartphone apps became technically feasible. Hence tools in order to plan and evaluate particular designs of information provision are needed. Since tests in real infrastructures are costly and environmental conditions cannot be held constant, one must resort to virtual infrastructures. This paper presents the development of an environment for the support of the design of indoor navigation systems whose center piece consists in a hands-free navigation method using the Microsoft Kinect in the four-sided Definitely Affordable Virtual Environment (DAVE). Navigation controls using the user's gestures and postures as the input to the controls are designed and implemented. The installation of expensive and bulky hardware like treadmills is avoided while still giving the user a good impression of the distance she has traveled in virtual space. An advantage in comparison to approaches using a head mounted display is that the DAVE allows the users to interact with their smartphone. Thus the effects of different indoor navigation systems can be evaluated already in the planning phase using the resulting system

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The purpose of this study was to compare four epidural protocols for peri-operative analgesia in dogs undergoing tibial plateau levelling osteotomy. Forty client-owned dogs were randomly assigned to one of four treatments - groups R0.5 and R1 received 0.5mg/kg and 1mg/kg ropivacaine, respectively. Group SR0.5 received 1mug/kg sufentanil plus 0.5mg/kg ropivacaine, and group SER0.5 received 1mug/kg sufentanil, 0.5mg/kg ropivacaine plus 6mug/kg epinephrine. Dilution, when required, was performed with saline, so that the injected volume was always 0.2mL/kg. Intra-operatively, nociception assessment was based on the evaluation of changes in heart rate, respiratory rate and mean arterial pressure. Post-operative pain assessment was performed using the Glasgow visual analogue pain scale, and an ad hoc multifactorial pain score. Motor block was evaluated using a modified Bromage score. Intra-operatively, none of the animals was hypotensive. All groups except SER0.5 required rescue intra-operative fentanyl (40%, 30% and 40% of the animals in groups R0.5, R1 and SR0.5, respectively). Group SER0.5 showed lower post-operative pain scores, and group R1 significantly greater motor block, compared to the other treatment groups. None of the dogs had urinary retention. Epidural sufentanil-epinephrine-ropivacaine provided superior peri-operative analgesia compared to the other treatments, without producing clinically relevant side effects.

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Screening for malignant disease aims to reduce the population risk of impaired health due to the tumor in question. Screening does not only entail testing but covers all steps required to achieve the intended reduction in risk, from the appropriate information of the population to a suitable therapy. Screening tests are performed in individuals free or unaware of any symptoms associated with the tumor. An essential condition is a recognizable pathological abnormality, which occurs without symptoms and represents a pre-clinical, early stage of the tumor. Overdiagnosis and overtreatment have only recently been recognized as important problems of screening for malignant disease. Overdiagnosis is defined as a screening-detected tumor that would never have led to symptoms. In prostate-specific antigen (PSA) screening for prostate cancer 50 % - 70 % of screening-detected cancers represent such overdiagnoses. Similarly, in the case of mammography screening 20 % - 30 % of screening-detected breast cancers are overdiagnoses. The evaluation of screening interventions is often affected by biases such as healthy screenee effects or length and lead time bias. Randomized controlled trials are therefore needed to examine the efficacy and effectiveness of screening interventions and to define the rate of adverse outcomes such as unnecessary diagnostic evaluations, overdiagnosis and overtreatment. Unfortunately there is no independent Swiss body comparable to the National Screening Committee in the United Kingdom or the United States Preventive Services Task Force, which examines screening tests and programs and develops recommendations. Clearly defined goals, a central organization responsible for inviting eligible individuals, documentation and quality assurance and balanced information of the public are important attributes of successful screening programs. In Switzerland the establishment of such programs is hampered by the highly fragmented, Federal health system which allows patients to access specialists directly.

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One hundred forty-four crossbred yearling steers with an average weight of 841 pounds were used in a 116- day experiment. Steers received either 1) no implant, 2) Synovex S¨, 3) Revalor S¨, or 4) Synovex Plus¨. All implanted groups consumed more feed and gained faster and more efficiently than non-implanted steers. There were no significant differences in gain, feed intake or feed efficiency among implanted groups, though steers with the estrogen + trenbolone acetate combination implants were numerically superior to those implanted with Synovex S¨. There were no differences in feedlot performance between the two combination implants. Implants increased carcass weight with no significant effects on fat thickness or carcass quality grades. The combination implants containing trenbolone acetate increased ribeye area and increased masculinity of the carcasses. These results indicate Synovex Plus¨ is an effective implant for finishing steers.

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Proteferm is a liquid by-product from the production of monosodium glutamate by fermentation that is 40% solids and contains 95% crude protein on a dry basis. Two trials were conducted with yearling steers to study the effects of different levels of Proteferm when added to 90% concentrate diets to replace corn and urea. Feeding Proteferm resulted in a decrease in urine pH, suggesting a metabolic acidosis that was probably caused by a negative cation–anion balance. Correcting the cation–anion imbalance resulted in an increase in feed intake and the performance of steers fed Proteferm as 1.5% of diet dry matter to be similar to the performance of control steers. Addition of sodium bicarbonate to the control diet or to the diet containing 1.5% Proteferm to produce a positive cation–anion balance did not improve performance. The results of these trials indicate that 1.5% Proteferm is the maximum that should be added to high concentrate diets fed to beef cattle without affecting performance or carcass value.

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BACKGROUND Preclinical and clinical studies suggest that a combination of enamel matrix derivative (EMD) with demineralized freeze-dried bone allograft (DFDBA) may improve periodontal wound healing and regeneration. To date, no single study has characterized the effects of this combination on in vitro cell behavior. The aim of this study is to test the ability of EMD to adsorb to the surface of DFDBA particles and determine the effect of EMD coating on downstream cellular pathways such as adhesion, proliferation, and differentiation of primary human osteoblasts and periodontal ligament (PDL) cells. METHODS DFDBA particles were precoated with EMD or human blood and analyzed for protein adsorption patterns via scanning electron microscopy. Cell attachment and proliferation were quantified using a commercial assay. Cell differentiation was analyzed using real-time polymerase chain reaction for genes encoding Runx2, alkaline phosphatase, osteocalcin, and collagen 1α1, and mineralization was assessed using alizarinred staining. RESULTS Analysis of cell attachment revealed no significant differences among control, blood-coated, and EMD-coated DFDBA particles. EMD significantly increased cell proliferation at 3 and 5 days after seeding for both osteoblasts and PDL cells compared to control and blood-coated samples. Moreover, there were significantly higher messenger ribonucleic acid levels of osteogenic differentiation markers, including collagen 1α1, alkaline phosphatase, and osteocalcin, in osteoblasts and PDL cells cultured on EMD-coated DFDBA particles at 3, 7, and 14 days. CONCLUSION The results suggest that the addition of EMD to DFDBA particles may influence periodontal regeneration by stimulating PDL cell and osteoblast proliferation and differentiation.

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Two experiments were conducted to evaluate the effects of body condition scores of beef calves on performance efficiency and carcass characteristics. In Experiment 1, 111 steer calves were stratified by breed and condition score (CS) and randomly allotted to 14 pens. The study was analyzed as a 2 x 3 factorial design, with two breeds (Angus and Simmental) and three initial CS (4.4, 5.1, and 5.6). In Experiment 2, 76 steer calves were allotted to six pens by CS. The resultant pens averaged 3.9, 4.5, 4.7, 5.0, 5.1, and 5.6 in CS. Calves in both studies were fed a corn-based finishing diet formulated to 13.5% crude protein. All calves were implanted with Synovex- SÒ initially and reimplanted with Revalor-SÒ. In Experiment 1, 29-day dry matter intake (lb/day) increased with CS (17.9, 18.1, and 19.1 for 4.4, 5.1, and 5.6, respectively; p < .04). Daily gain (29 days) tended to decrease with increasing CS (4.19, 3.71, and 3.26; p < .13). Days on feed decreased with increasing CS (185, 180, and 178d; p < .07). In Experiment 2, daily gains also increased with decreasing initial CS for the first 114 days (p < .05) and tended to increase overall (p < .20). In Experiment 1, calves with lower initial CS had less external fat at slaughter (.48, .53, and .61 in. for CS 4.4, 5.1, and 5.6, respectively; p < .05). This effect was also noted at slaughter (p < .10), as well as at 57 days (p < .06) and at 148 days (p < .06) as measured by real-time ultrasound. Measurements of intramuscular fat and marbling were not different in either study. These data suggest that CS of feeder calves may be a useful tool for adjusting energy requirements of calves based on body condition. Also, feeder cattle may be sorted into outcome or management groups earlier than currently practiced using body condition and/or real-time ultrasound.

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Rationale, aims and objectives  The study aims to investigate the effects of a patient safety advisory on patients' risk perceptions, perceived behavioural control, performance of safety behaviours and experience of adverse incidents. Method  Quasi-experimental intervention study with non-equivalent group comparison was used. Patients admitted to the surgical department of a Swiss large non-university hospital were included. Patients in the intervention group received a safety advisory at their first clinical encounter. Outcomes were assessed using a questionnaire at discharge. Odds ratios for control versus intervention group were calculated. Regression analysis was used to model the effects of the intervention and safety behaviours on the experience of safety incidents. Results  Two hundred eighteen patients in the control and 202 in the intervention group completed the survey (75 and 77% response rates, respectively). Patients in the intervention group were less likely to feel poorly informed about medical errors (OR = 0.55, P = 0.043). There were 73.1% in the intervention and 84.3% in the control group who underestimated the risk for infection (OR = 0.51, CI 0.31-0.84, P = 0.009). Perceived behavioural control was lower in the control group (meanCon  = 3.2, meanInt  = 3.5, P = 0.010). Performance of safety-related behaviours was unaffected by the intervention. Patients in the intervention group were less likely to experience any safety-related incident or unsafe situation (OR for intervention group = 0.57, CI 0.38-0.87, P = 0.009). There were no differences in concerns for errors during hospitalization. There were 96% of patients (intervention) who would recommend other patients to read the advisory. Conclusions  The results suggest that the safety advisory decreases experiences of adverse events and unsafe situations. It renders awareness and perceived behavioural control without increasing concerns for safety and can thus serve as a useful instrument for communication about safety between health care workers and patients.

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OBJECTIVES This study sought to study the efficacy and safety of newer-generation drug-eluting stents (DES) compared with bare-metal stents (BMS) in an appropriately powered population of patients with ST-segment elevation myocardial infarction (STEMI). BACKGROUND Among patients with STEMI, early generation DES improved efficacy but not safety compared with BMS. Newer-generation DES, everolimus-eluting stents, and biolimus A9-eluting stents, have been shown to improve clinical outcomes compared with early generation DES. METHODS Individual patient data for 2,665 STEMI patients enrolled in 2 large-scale randomized clinical trials comparing newer-generation DES with BMS were pooled: 1,326 patients received a newer-generation DES (everolimus-eluting stent or biolimus A9-eluting stent), whereas the remaining 1,329 patients received a BMS. Random-effects models were used to assess differences between the 2 groups for the device-oriented composite endpoint of cardiac death, target-vessel reinfarction, and target-lesion revascularization and the patient-oriented composite endpoint of all-cause death, any infarction, and any revascularization at 1 year. RESULTS Newer-generation DES substantially reduce the risk of the device-oriented composite endpoint compared with BMS at 1 year (relative risk [RR]: 0.58; 95% confidence interval [CI]: 0.43 to 0.79; p = 0.0004). Similarly, the risk of the patient-oriented composite endpoint was lower with newer-generation DES than BMS (RR: 0.78; 95% CI: 0.63 to 0.96; p = 0.02). Differences in favor of newer-generation DES were driven by both a lower risk of repeat revascularization of the target lesion (RR: 0.33; 95% CI: 0.20 to 0.52; p < 0.0001) and a lower risk of target-vessel infarction (RR: 0.36; 95% CI: 0.14 to 0.92; p = 0.03). Newer-generation DES also reduced the risk of definite stent thrombosis (RR: 0.35; 95% CI: 0.16 to 0.75; p = 0.006) compared with BMS. CONCLUSIONS Among patients with STEMI, newer-generation DES improve safety and efficacy compared with BMS throughout 1 year. It remains to be determined whether the differences in favor of newer-generation DES are sustained during long-term follow-up.