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Operational skills involved in controlling a motor vehicle were measured in two groups of very healthy elderly drivers and a young control group to test the hypothesis that there are age-related declines in operational performance that may influence driver safety. An actual behind-the-wheel, standardized road test was employed using a motor vehicle equipped with sensors to record speed, braking activity, and lane position, as well as direction and magnitude of front-wheel and eye-movement excursions. The data from these sensors were used as dependent measures of operational performance. Older drivers made fewer steering and eye-movement excursions and drifted across the center line more frequently than the young control group. Younger drivers drove significantly faster and executed more braking applications than did their older counterparts. The motor-vehicle operational performance of older healthy drivers was related to visual-spatial attentional declines and the useful field of vision associated with the normal aging process.  相似文献   
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In order to characterize the role of carnitine during metabolic stress, we prospectively determined carnitine profiles in plasma and urine on admission, days 2, 5, 10 and 15, among 28 critically ill children free of any known conditions associated with secondary carnitine deficiency. More than 25% of plasma and 50% of urinary carnitine measurements were abnormal; 96% (27/28) of patients displayed on at least one occasion an abnormal [< -2 SD or > +2 SD] carnitine value in plasma. Three children had extremely low [< 10 micromol/l] free carnitine (FC) levels in plasma. Plasma esterified and FC levels on admission were not related to the risk of mortality [PRISM score], to muscle lysis [CK values], and to the caloric intake. Levels of FC and esterified carnitine in plasma were unrelated to those measured in urine. Conclusion: Abnormal plasma and urine carnitine measurements are frequently found in critically ill children; the biological significance of these perturbations remains unclear. Caution must be exercised before concluding that an abnormal carnitine value is indicative of an underlying hereditary metabolic disorder in this population.  相似文献   
4.
A man with double inlet left ventricle and severe subpulmonary stenosis underwent a Fontan operation at the age of 29 years. Eight years later he developed atrial flutter with complete heart block. To avoid a further thoracotomy, a unipolar carbon tipped electrode was placed into the posterior cardiac vein via the coronary sinus. More than 8 years after implantation of the original lead, and after two generator changes, telemetric thresholds remain between 1.8-2.1 volts. Percutaneous transvenous ventricular pacing via the coronary sinus can produce an excellent long-term result and should be the initial approach of choice after a Fontan-type operation.  相似文献   
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Visual Cryptography (VC) is gaining attraction during the past few years to secure the visual information in the transmission network. It enables the visual data i.e. handwritten notes, photos, printed text, etc. to encrypt in such a way that their decryption can be done through the human visual framework. Hence, no computational assistance is required for the decryption of the secret images they can be seen through naked eye. In this paper, a novel enhanced halftoning-based VC scheme is proposed that works for both binary and color images. Fake share is generated by the combination of random black and white pixels. The proposed algorithm consists of 3 stages i.e., detection, encryption, and decryption. Halftoning, Encryption, (2, 2) visual cryptography and the novel idea of fake share, make it even more secure and improved. As a result, it facilitates the original restored image to the authentic user, however, the one who enters the wrong password gets the combination of fake share with any real share. Both colored and black images can be processed with minimal capacity using the proposed scheme.

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6.
Natural rubber is one of the most potential electro-active polymers for sensors, actuators, and energy harvesting applications. Enhancing the characteristic properties of polymers by reinforcing with fillers that possess multifunctional attributes have attracted considerable attention. In the present study, barium titanate reinforced natural rubber composite is prepared by using two-roll mill mixing. Afterwards, mechanical, electrical, and electromechanical properties of the composites are extensively analyzed by reinforcing different amounts of barium titanate into the matrix of natural rubber. The fabricated dielectric composite shows excellent properties such as high dielectric constant, low dielectric losses, high dielectric breakdown strength, and extreme stretchability. It is observed that as the filler loading reaches the value of 11 parts per hundred rubber (phr), maximum agglomeration of the particles occurs. Maximum stretchability and highest ratio of dielectric constant to elastic modulus are obtained at 8 phr of barium titanate fillers and at the loading, a maximum actuation strain of 11.24% is achieved. This study provides a simple, economical, and effective method for preparing enhanced mechanical, electrical, and electromechanical properties of natural rubber composites, facilitating the wide applications of dielectric materials as actuators and generators.  相似文献   
7.
Arshad  Madiha  Qureshi  Mahmood  Inam  Omair  Omer  Hammad 《Magma (New York, N.Y.)》2021,34(5):717-728
Magnetic Resonance Materials in Physics, Biology and Medicine - The success of parallel Magnetic Resonance Imaging algorithms like SENSitivity Encoding (SENSE) depends on an accurate estimation of...  相似文献   
8.
The commonly used LRU replacement policy causes thrashing for memory- intensive workloads. A simple mechanism that dynamically changes the insertion policy used by LRU replacement reduces cache misses by 21 percent and requires a total storage overhead of less than 2 bytes.  相似文献   
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A country’s economy heavily depends on agricultural development. However, due to several plant diseases, crop growth rate and quality are highly suffered. Accurate identification of these diseases via a manual procedure is very challenging and time-consuming because of the deficiency of domain experts and low-contrast information. Therefore, the agricultural management system is searching for an automatic early disease detection technique. To this end, an efficient and lightweight Deep Learning (DL)-based framework (E-GreenNet) is proposed to overcome these problems and precisely classify the various diseases. In the end-to-end architecture, a MobileNetV3Small model is utilized as a backbone that generates refined, discriminative, and prominent features. Moreover, the proposed model is trained over the PlantVillage (PV), Data Repository of Leaf Images (DRLI), and a new Plant Composite (PC) dataset individually, and later on test samples, its actual performance is evaluated. After extensive experimental analysis, the proposed model obtained 1.00%, 0.96% and 0.99% accuracies on all three included datasets. Moreover, the proposed method achieves better inference speed when compared with other State-Of-The-Art (SOTA) approaches. In addition, a comparative analysis is conducted where the proposed strategy shows tremendous discriminative scores as compared to the various pre-trained models and other Machine Learning (ML) and DL methods.  相似文献   
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