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1.
Two proprietary biocides were compounded and extruded at three concentrations, respectively, into high density polyethylene-maple wood flour lumber (HDPE-MWL) and evaluated for their efficacy to control fungal colonization and discoloration using the ASTM Standard G 21-96. Although the silver biocide used in this study did not control fungal colonization and discoloration of HDPE-MWL, statistically significant difference was observed between the highest silver biocide concentration and those of the two lower silver biocide concentrations. The latter exhibited no significant difference with the controls. In contrast, the three levels of zinc biocides showed significant difference from each other with respect to their efficacy against fungal colonization and discoloration of HDPE-MWL. Overall, only the zinc biocide was efficacious against fungal colonization and discoloration. The biocide containing zinc as an active biocidal agent was most efficacious at 1% (by weight) concentration. 相似文献
2.
Xiao-Ying Wang Jonathan M. Garibaldi Benjamin Bird Michael W. George 《Applied Intelligence》2007,27(3):237-248
Recently Fourier Transform Infrared (FTIR) spectroscopic imaging has been used as a tool to detect the changes in cellular
composition that may reflect the onset of a disease. This approach has been investigated as a mean of monitoring the change
of the biochemical composition of cells and providing a diagnostic tool for various human cancers and other diseases. The
discrimination between different types of tissue based upon spectroscopic data is often achieved using various multivariate
clustering techniques. However, the number of clusters is a common unknown feature for the clustering methods, such as hierarchical
cluster analysis, k-means and fuzzy c-means. In this study, we apply a FCM based clustering algorithm to obtain the best number
of clusters as given by the minimum validity index value. This often results in an excessive number of clusters being created
due to the complexity of this biochemical system. A novel method to automatically merge clusters was developed to try to address
this problem. Three lymph node tissue sections were examined to evaluate our new method. These results showed that this approach
can merge the clusters which have similar biochemistry. Consequently, the overall algorithm automatically identifies clusters
that accurately match the main tissue types that are independently determined by the clinician. 相似文献
3.
4.
MG Fehlings T Errico P Cooper V Benjamin T DiBartolo 《Canadian Metallurgical Quarterly》1993,32(2):198-207; discussion 207-8
Although occipitocervical fusion is frequently used for instability of the upper cervical spine and the occipitocervical articulation, most currently used techniques have one or more of the following disadvantages: the necessity for sublaminar wires, the use of occipital screws, a fixed angle of instrumentation, or the necessity for routine postoperative halo immobilization. Moreover, many reported techniques are associated with a high rate of nonunion or instrumentation failure. We present our experience with a technically simple method of obtaining rigid occipitocervical arthrodesis using a 5-mm malleable rod that is fixed to the skull by a pair of wires passed through four suboccipital burr holes. Segmental spinal fixation is achieved with Wisconsin interspinous wires and is occasionally supplemented with sublaminar wires. Supplemental autogenous bone graft is used in all cases. A cervical collar is routinely used for postoperative immobilization. The results of treatment were retrospectively reviewed in 16 patients with an average age of 49.4 years (range, 9-69). Mean follow-up was 24 months (range, 12-36 mo). The indication for fusion was instability of the occiput-C1-C2 complex as a result of Chiari malformation, rheumatoid disease, skull base tumor resection, basilar invagination, ankylosing spondylitis, Down's syndrome, cervical laminectomy, and trauma. The average number of levels fused was 5.4 (range, O-C3 to O-T3). Successful occipitocervical arthrodesis was achieved in all but one of the surviving patients. The single patient with a pseudarthrosis was successfully managed with supplemental bone grafting and halo immobilization. There were two deaths from medical complications in chronically ill patients. Other complications included one postoperative instrumentation loosening, one myocardial infarction, and one superficial occipital decubitus. In conclusion, rodding and segmental interspinous wiring is an effective, technically simple method of obtaining rigid occipitocervical fixation, which obviates the need for bulky orthoses. 相似文献
5.
Chen L.R. Benjamin S.D. Smith P.W.E. Sipe J.E. 《Quantum Electronics, IEEE Journal of》1998,34(11):2117-2129
We discuss theoretical and experimental studies on the propagation of ultrashort pulses through fiber Bragg gratings. We also consider several applications in optical communications to be found by combining ultrashort pulses and fiber Bragg gratings: a multiwavelength source for wavelength-division-multiplexed systems and a means for implementing optical code-division multiple access 相似文献
6.
Low-temperature-grown GaAs (LT-GaAs) is a promising material for all-optical switching devices due to its outstanding optical characteristics. In this paper, we outline a simplified model we have developed to describe the dynamics of the carriers in this material. We also report the results of a series of measurements that we have performed to characterize the optical properties of the material. Specifically, we present the first measurements of the two-photon absorption coefficient and the refractive index changes as a function of the growth and annealing temperatures in LT-GaAs. Finally, we show how our model can be used to optimize the material for applications in all-optical switching 相似文献
7.
The object of this paper is to demonstrate the usefulness of the transalkylation reaction for determining chemical structural features of products derived from coal. For example, the method is applied to derivatized coals, coals modified by thermolysis, and materials physically or chemically separated from coals. Data are presented for the pyridine soluble and insoluble parts of two coals, an O-methylated coal, a Birch reduced coal, a solvent refined coal, and a coke. Similarities and differences in chemical make-up of these materials are discussed. 相似文献
8.
Hartouni E.P. Jensen D.A. Klima B. Kreisler M.N. Rabin M.S.Z. Uribe J. Church M. Gara A. Gottschalk E. Hylton R. Knapp B.C. Sippach F.W. Stern B. Wiencke L. Christian D. Gutierrez G. Holmes S.D. Strait J.B. Wehmann A. Avilez C. Correa W. Rosales A. Forbush M. Huson F.R. White J. 《IEEE transactions on nuclear science》1989,36(5):1480-1484
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented 相似文献
9.
Dr. Sabine Wicker Prof. Dr. Holger Rabenau Priv.-Doz. Dr. Dr. Rene Gottschalk 《Ethik in der Medizin》2007,19(3):216-218
Ohne Zusammenfassung 相似文献
10.
J Gottschalk G Jautzke S M?rzheuser-Brands J Cervos-Navarro 《Canadian Metallurgical Quarterly》1993,139(4-5):343-349
Occasionally variants of meningeal hemangiopericytomas (HPC) may be confused with primary and secondary tumours of the meninges by virtue of their features and patterns of growth. Until now, a specific immunohistochemical marker for HPC could not be identified. HPC are reported to express factor XIIIa (F XIIIa) in the cytoplasm of the tumour cells. In an effort to assess the diagnostic value of F XIIIa for meningeal HPC, we investigated 38 primary meningeal tumours (6 HPC, 28 meningiomas of various subtypes, 4 meningeal sarcomas) and 23 secondary meningeal tumors (8 metastatic carcinomas, 6 gliosarcomas, 9 anaplastic gliomas) with anti-F XIIIa antibody. All HPC revealed 5%-20% of F-XIIIa-positive neoplastic cells. Malignant fibrous histiocytomas and gliosarcomas with MFH-like structures also exhibited multiple F-XIIIa-positive cells. Most of the F-XIIIa-positive cells in meningiomas were identified as macrophages. Furthermore, there was a population of small dark cells of uncertain histogenesis. Cells with positive immunoreactivity for F-XIIIa in metastatic carcinomas and gliomas apparently were of macrophage lineage. Though, in some cases, it would have been difficult to distinguish reactive from neoplastic cells without simultaneous immunohistochemical investigation with antibodies for macrophages, cytokeratin, EMA and GFAP. Because of these uncertainties, wo believe that the potential of F XIIIa-antibody in obtaining precise differential diagnostic information is limited. 相似文献