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761.
The nuclease activities of proteins, constituents of cytoplasmic ribosomes obtained from normal liver rats (Wistar) and C3HA mice as well as from hepatomas (both solid and ascites forms) transplanted into the above animals, were studied. RNA in membrane-bound ribosomes of normal rat liver incubated at 37 degrees C undergoes endogeneous hydrolysis resulting in formation, apart from acid-soluble products, of 6S, 8S and 11S fragments comprising 15 to 20% of the original amount of RNA. In contrast, in hepatoma membrane-bound ribosomes RNA treated likewisely remains intact. The proteins responsible for the RNase activity isolated from ribosomes were subsequently fractionated using ammonium sulfate and chromatography on DEAE-Sephadex columns and their properties were studied. The RNase activity completely disappeared from the membrane-bound ribosomes of Zajdela, 27 rat hepatomas and Guelstein hepatoma 22A, but not from the slow growing Guelstein hepatoma 48. 相似文献
762.
Li-Zhen Deng Arun S. Mujumdar Sriram K. Vidyarthi Jinwen Xu Magdalena Zielinska 《Critical reviews in food science and nutrition》2020,60(15):2481-2508
Abstract With a growing demand for safe, nutritious, and fresh-like produce, a number of disinfection technologies have been developed. This review comprehensively examines the working principles and applications of several emerging disinfection technologies. The chemical treatments, including chlorine dioxide, ozone, electrolyzed water, essential oils, high-pressure carbon dioxide, and organic acids, have been improved as alternatives to traditional disinfection methods to meet current safety standards. Non-thermal physical treatments, such as UV-light, pulsed light, ionizing radiation, high hydrostatic pressure, cold plasma, and high-intensity ultrasound, have shown significant advantages in improving microbial safety and maintaining the desirable quality of produce. However, using these disinfection technologies alone may not meet the requirement of food safety and high product quality. Several hurdle technologies have been developed, which achieved synergistic effects to maximize lethality against microorganisms and minimize deterioration of produce quality. The review also identifies further research opportunities for the cost-effective commercialization of these technologies. 相似文献
763.
Computational grids allow the sharing of geographically distributed computational resources in an efficient, reliable, and secure manner. Grid is still in its infancy, and there are many problems associated with the computational grid, namely job scheduling, resource management, information service, information security, routing, fault tolerance, and many more. Scheduling of jobs on grid nodes is an NP‐class problem warranting for heuristic and meta‐heuristic solution approach. In the proposed work, a meta‐heuristic technique, auto controlled ant colony optimization, has been applied to solve this problem. The work observes the effect of interprocess communication in process to optimize turnaround time of the job. The proposed model has been simulated in Matlab. For the different scenarios in computational grid, results have been analyzed. Result of the proposed model is compared with another meta‐heuristic technique genetic algorithm that has been applied for the same purpose. It is found that auto controlled ant colony optimization not only gives better solution in comparison to genetic algorithm, but also converges faster because initial solution itself is good because of constructive and decision‐based policy adapted by the former. Concurrency and Computation: Practice and Experience, 2012.© 2012 Wiley Periodicals, Inc. 相似文献
764.
1. Previous studies have used tendon vibration to investigate kinesthetic illusions in the isometric limb and end point control in the moving limb. These previous studies have shown that vibration distorts the perceptions of static joint angle and movement and causes systematic errors in the end point of movement. In this paper we describe the effects of tendon vibration during movement while human subjects performed a proprioceptively coordinated motor task. In an earlier study we showed that the CNS coordinates this motor task-a movement sequence-with proprioceptive information related to the dynamic position and velocity of the limb. 2. When performing this movement sequence, each subject sat at a table and opened the right hand as the right elbow was passively rotated in the extension direction through a prescribed target angle. Vision of the arm was prevented, and the movement velocity was changed randomly from trial to trial, leaving proprioception as the only useful source of kinematic information with which to perform the task. 3. In randomly occurring trials, vibration was applied to the tendon of the biceps brachii, a muscle that lengthens during elbow extension. In some experiments the timing of tendon vibration was varied with respect to the onset of elbow rotation, and in other experiments the frequency of vibration was varied. In each experiment we compared the accuracy of the subject's response (i.e., the elbow angle at which the subject opened the hand) in trials with tendon vibration with the accuracy in trials without tendon vibration. 4. The effect of tendon vibration depended on the frequency of vibration. When the biceps tendon was vibrated at 20 Hz, subjects opened the hand after the elbow passed through the target angle ("overshooting"). Overshooting is consistent with an underestimate of the actual displacement or velocity of the elbow. Vibration at 30 Hz had little or no effect on the elbow angle at hand opening. Vibration at 40 Hz caused subjects to open the hand before the elbow reached the target angle ("undershooting"). Undershooting is consistent with an overestimate of the actual displacement or velocity of the elbow. The size of the error depended on the velocity of the passively imposed elbow rotation. 5. The effect of tendon vibration also depended on the timing of vibration. If 40-Hz vibration began at the onset of movement, the subject undershot the target. If 40-Hz vibration started 5 s before movement onset and continued throughout the movement, the undershoot error increased in magnitude. However, if 40-Hz vibration started 5 s before movement onset and then stopped at movement onset, the subject overshot the target. When vibration was shut off during movement, a transition occurred from an over-shooting error to an undershooting error at a time that depended on the velocity of elbow rotation. 6. In a separate experiment, subjects were instructed to match either the perceived dynamic position or the perceived velocity of rotation imposed on the right elbow by actively rotating the left elbow. In both matching tasks, tendon vibration produced oppositely directed errors depending on the frequency of vibration. Vibration at 20 Hz produced a perception of decreased elbow velocity and a bias in dynamic position in the flexion direction, and vibration at 40 Hz produced the opposite perceptions. 7. We conclude that muscle spindle afferents, which are activated by tendon vibration, are an important source of the dynamic position and velocity information that the CNS uses to coordinate this movement sequence task. The observed effects of vibration timing and frequency suggest that perceptual changes evoked by vibration cannot be explained by the simple summation of sensory input evoked by movement and by vibration. Rather, the bias in perception produced by vibration appears to be related to the difference between vibration- and movement-evoked activity in muscle spindle afferents. 相似文献
765.
Liver failure and death after exposure to microcystins at a hemodialysis center in Brazil 总被引:5,自引:0,他引:5
EM Jochimsen WW Carmichael JS An DM Cardo ST Cookson CE Holmes MB Antunes DA de Melo Filho TM Lyra VS Barreto SM Azevedo WR Jarvis 《Canadian Metallurgical Quarterly》1998,338(13):873-878
BACKGROUND: Hemodialysis is a common but potentially hazardous procedure. From February 17 to 20, 1996, 116 of 130 patients (89 percent) at a dialysis center (dialysis center A) in Caruaru, Brazil, had visual disturbances, nausea, and vomiting associated with hemodialysis. By March 24, 26 of the patients had died of acute liver failure. METHODS: A case patient was defined as any patient undergoing dialysis at dialysis center A or Caruaru's other dialysis center (dialysis center B) during February 1996 who had acute liver failure. To determine the risk factors for and the source of the outbreak, we conducted a cohort study of the 130 patients at dialysis center A and the 47 patients at dialysis center B, reviewed the centers' water supplies, and collected water, patients' serum, and postmortem liver tissue for microcystin assays. RESULTS: One hundred one patients (all at dialysis center A) met the case definition, and 50 died. Affected patients who died were older than those who survived (median age, 47 vs. 35 years, P<0.001). Furthermore, all 17 patients undergoing dialysis on the Tuesday-, Thursday-, and Saturday-night schedule became ill, and 13 of them (76 percent) died. Both centers received water from a nearby reservoir. However, the water supplied to dialysis center B was treated, filtered, and chlorinated, whereas the water supplied to dialysis center A was not. Microcystins produced by cyanobacteria were detected in water from the reservoir and from dialysis center A and in serum and liver tissue of case patients. CONCLUSIONS: Water used for hemodialysis can contain toxic materials, and its quality should therefore be carefully monitored. 相似文献
766.
Harshit Bhardwaj Pradeep Tomar Aditi Sakalle Arpit Bhardwaj Rishi Asthana Ankit Vidyarthi 《Asian journal of control》2023,25(5):3330-3342
The reliable correlation between personality and brain signal ensures that inferences from cognitive processes can be achieved. This research aims primarily to predict one's personality using brain signals. On grounds of Psychology, the inference of personality in this work is performed on the basis of the Myers–Briggs Type Indicator (MBTI) personality inventory. Personality consists of different types of thinking, feeling and behavior patterns. EEG signals are produced when a person is exposed to situations or scenarios via visual information and experiences various emotions or sentiments. In this study, by evaluating brain waves while a person watches personality traits elicitation materials, the identification of the personality traits of an individual is done. The elicitation materials used for the collection of the dataset comprise approximately 50 videos with the pre-defined personality of the dramatic personae and therefore, it is considered to be the ground truth for the experimental procedure of this work. For creating a dataset, sixty participants contributed and gave brain signals. The GP model with the proposed BSH crossover, known as the BSHGP model, is implemented. The maximum performance of the BSHGP model for a 10-fold partition scheme is 84.34%. 相似文献