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1.
322 men who had not prostatic diseases were selected at random for defining the characteristics of serum prostate specific antigen (PSA) in order to use PSA more appropriately in detecting clinically significant prostate cancer. The serum PSA concentration is correlated with patient age (r = 0.301; P < 0.0001), PSA is increased with age. The recommended upper limits (mean +2 standard deviations) for serum PSA for men aged 20-49 years was 2.71 ng/ml; for 50-59 years, 5.01ng/ml; for 60-69 years, 6.05 ng/ml; and for greater than or equal to 70 years, 7.92 ng/ml. Our findings led to proposals for using age-specific PSA reference range instead of a single reference range for men of all age groups. These age-specific reference ranges have the potential to increase the specificity of using PSA for detecting prostate cancer. 相似文献
2.
The Harmony Search (HS) is a metaheuristic algorithm, which is inspired from the composition of music harmonies. The functionality and flexibility of HS contribute to the development of successful methodologies for different kind of scientific problems. The aim of this paper is to propose a variant of the classic HS algorithm in order to provide competitive solutions for the Team Orienteering Problem (TOP). We introduce the Similarity Hybrid Harmony Search (SHHS) algorithm as an alternative and innovative optimization method. The SHHS follows the standard procedure of HS with some modifications and includes a new strategy called “similarity process”. Two versions of the proposed method have been developed, the static version with predefined values for the parameters of the method and the dynamic one with dynamic adjustment of the parameters. The SHHS algorithm is applied to the known benchmark instances of TOP. The dynamic of the algorithm is tested through a complete solution analysis which gives the superiority of the dynamic version compared to the static one. The results of both versions of the proposed algorithm indicate the positive performance against other effective and robust optimization algorithms from the literature. 相似文献
3.
In this paper, we put forward an effective and efficient no reference image blurriness assessment metric on the basis of local binary pattern (LBP) features. In this proposal, we reveal that part of the LBP histogram bins present monotonously with the degree of blurriness. The proposed method contains the following steps. Firstly, the LBP maps of an input image are extracted with multiple radiuses. And then, the frequency of pattern histogram is analyzed before part of bins are chosen as the features. In addition, we also take the entropy of these bins as another feature. Finally, we learn the extracted features to predict the image blurriness score. Validation of the proposed method is conducted on the blurred images of LIVE-II, CSIQ, TID2008, TID2013, LIVE3D IQA Phase I and LIVE3D IQA Phase II. Experimental results demonstrate that compared with the state-of-the-art image quality assessment (IQA) methods, the proposed algorithm has notable advantage in correlation with subjective perception and computational complexity. 相似文献
4.
《Materials Letters》2007,61(23-24):4579-4582
A novel ethylene dichloride solvent-assisted route has been successfully developed to coat uniformly polystyrene colloids with Ag and prepare the corresponding hollow spheres. In this route, by corroding and swelling the PS colloid surface with ethylene dichloride, Ag seeds are synthesized directly in and on the surface layer of core, not only the surface functionalization is avoided, but also may enhance the combination of core and seeds. The ethylene dichloride concentration is crucial for the coating results. The coverage, thickness, and roughness of the Ag shell can be effectively controlled by varying the amount of HCHO during the seeding growth process, and the as-prepared composites can crystallize into ordered structure. This coating route is facile and versatile, and apt to coat PS colloids with other metal and prepare the corresponding hollow metal spheres. 相似文献
5.
本文介绍一种用免疫扫描电镜技术研究病毒感染的细胞表面的简易制样方法。适当控制镀金膜的厚度(约5nm厚),即可观察到直径仅20nm胶体金标记物的二次电子图象。与近年来发展起来的背散射成象法比较,细胞表面甚至病毒粒子的形貌更为清晰。 相似文献
6.
7.
《International Journal of Hydrogen Energy》2023,48(66):25712-25719
Efficient non-noble metal bifunctional electrocatalysts for overall water splitting in pH universal is highly desired in application. Herein, MnO2/graphene composition are applied as efficient electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in pH-universal electrolytes with the help of plasma dc arc method. The couple of MnO2 and graphene highly benefits to the H2O, H+ and OH− absorption respectively. The defects and stable Mn3+ contribute to the transfer of electron and charge. The low overpotentials and small Tafel slopes reveal attractive activities of HER and OER. The good electrocatalytic performances are attributed to the synergistic effect and abundant heterogeneous interfaces in MnO2/graphene. These can offer rich electroactive sites and accelerate electron transfer. Thus, it may provide facile route for developing nonprecious electrocatalysts of water splitting. 相似文献
8.
JV Tighe 《Canadian Metallurgical Quarterly》1996,49(3):187-189
The delto-pectoral flap has been used to repair burned scar in the faciocervical region for some years. However, its limited size restricts its application. Furthermore, direct transfer of the flap may result in a swelling and inexpressive face and the donor site needs skin grafting. To avoid the above disadvantages, we have tried pre-expansion of the flap. In this article, the authors report the experiences in the application of the method to eighteen cases, including the surgical procedure, the applied anatomy, and typical cases as well. Also included in the article are the comparison between various therapies to the burned scar of the face, the key points for successful pre-expansion of the delto-pectoral flap, accurately maintaining the desired position. The method has been proved to have many advantages and can be widely applied. 相似文献
9.
《Composites Science and Technology》2007,67(3-4):325-335
Four stitched graphite/epoxy laminates of different thicknesses were subjected to high-velocity impact tests. Two steel spheres, 12.7 and 20 mm in diameter, were used as bullets during the tests, carried out at two different speeds (65 and 129 m/s). Perforation occurred only under some of the experimental conditions adopted, whereas rebound was verified in other cases. As expected, the perforation energy increased with increasing the panel thickness and projectile diameter.In order to predict the perforation energy as a function of target thickness and bullet diameter, the Reid and Wen model and the Cantwell and Morton model were used. The Cantwell and Morton model was suitably modified: a new hypothesis was made, and an easier formulation, needing a single constant to be experimentally determined, was obtained.The dependence of perforation energy on laminate thickness was well described by the models considered, which provided very similar predictions. The same happened for the rebound conditions. However, only the modified Cantwell and Morton formula was effective in modelling the influence of the impactor diameter, while the Reid and Wen model provided a theoretical value about 50% higher than the measured one.The delaminated area was measured by ultrasonic C-scan in pulse-echo mode. It was found that a linear relationship links the delamination extent and the maximum energy absorbed by the panel, whichever the specimen thickness and projectile diameter. This correlation becomes ineffective for thick laminates, probably because of a change in failure modes occurring at sufficiently high thicknesses. 相似文献
10.
At rest position and varied clenching levels at intercuspal position, autoregressive (AR) models of myoelectrical activities of both masseter and anterior temporal muscles of 11 healthy subjects with intact natural dentitions were established. The relationship between the AR model coefficients of surface EMGs and their potentials was analyzed by multiple linear regression. It was found that the fourth order coefficient of AR had the greatest effect on the EMG potential levels and their relationship was positive in all recorded muscles. The results indicate the AR coefficients may become a characteristic parameter to describe myoelectrical activity of jaw closing muscles. 相似文献