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In addition to the well-known Shannon entropy, generalized entropies, such as the Renyi and Tsallis entropies, are increasingly used in many applications. Entropies are computed by means of nonparametric kernel methods that are commonly used to estimate the density function of empirical data. Generalized entropy estimation techniques for one-dimensional data using sample spacings are proposed. By means of computational experiments, it is shown that these techniques are robust and accurate, compare favorably to the popular Parzen window method for estimating entropies, and, in many cases, require fewer computations than Parzen methods.  相似文献   
3.
We report the first case of a child with mild dystrophinopathy associated with Klinefelter's syndrome (karyotype 47, XXY). This 3.5-year-old boy was affected by some symptoms suggestive of Becker's muscular dystrophy. Dystrophin immunostaining and immunoblotting procedures confirmed the diagnosis, but polymerase chain reaction-directed gene analysis failed to reveal any macrodeletion. Methylation-based assay did not show preferential X-inactivation. This confirmed the coexistence of the two active X-chromosomes (one of which was of paternal origin), thus accounting for the mild form of dystrophinopathy in this child affected by Klinefelter's syndrome.  相似文献   
4.
Presentation of a new type of chromium diffusion layer obtained on 0.5 % C carbon steel by termit process. Microstructure, phase composition and chemical composition of the layer obtained after various chromizing conditions. Determination of the growth mechanism of layer based on Fe-Cr-C equilibrium diagrams.  相似文献   
5.
Uses the stages of adult development set forth by G. Sheehy (1976) as a model for analyzing the careers of counseling psychologists. The careers of counseling center personnel are traced from graduate school days to the period Sheehy refers to as resignation or renewal, and the following conclusions are made: (a) The counseling center career ladder is short, forcing many psychologists in their early 30's into other job avenues; (b) the flexibility provided by counseling center positions is a 2-edged sword, producing disadvantages in later career stages; (c) reward systems should be developed to keep competent therapists in the counseling center; (d) administrative training should be provided during graduate school for future counseling psychologists; and (e) renewal alternatives need to be developed for burned-out counselors and counseling center directors in the midlife transition. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Pd/Mg bilayers and Pd/Al/Mg trilayers were prepared onto glass substrates at room temperature (RT) by UHV magnetron sputtering. Mixing effects at the Pd–Mg and Al–Mg interfaces were studied in-situ, immediately after deposition, by X-ray Photoelectron Spectroscopy (XPS). Additionally, the interfaces of the Pd/Al/Mg trilayer for the Al thickness equal to 1 nm were examined. Hydrogen absorption was monitored in-situ at RT by simultaneous resistivity and optical transmittance measurements. Formation of MgH2 phase was confirmed by ex-situ X-ray diffraction measurements. The XPS studies revealed rather sharp interface between Al and Mg layers. On the other hand, a significant interface mixing for the Pd/Mg bilayers and Pd/1 nm – Al/Mg trilayers was observed. Further studies showed that an additional layer of Al, deposited between magnesium and palladium layers, can significantly improve the hydrogen absorption kinetics at RT. The optimal thickness of the Al layer was found to be 0.5 nm.  相似文献   
7.
Determination of Iron Species in Samples of Iron-Fortified Food   总被引:1,自引:0,他引:1  
The paper presents the determination of iron forms in food products. The procedure of sample extraction was developed and optimized, preserving the content of particular forms of iron. The colorimetric method using 2,2′-bipirydyl (measurements at 520 nm) was applied in Fe(II) determinations, while in Fe(III) determinations, the colorimetric method with potassium thiocyanate (measurements at 470 nm) was applied. The total content of iron was determined by the technique of atomic absorption spectrometry, which allowed for the determination of iron content in organic and inorganic complex compounds. Detection limits of 1 mg kg?1 were obtained for all determined iron forms, with the precision ranging between 0.7 % and 1.5 % for 10 mg kg?1 concentration. The optimized analytical procedure was applied in the determinations of iron forms in iron-fortified food products.  相似文献   
8.
A pilot study was performed to evaluate the feasibility of using the Internet to securely deliver patient laboratory results, and the system has subsequently gone into routine use in Poland. The system went from design to pilot and then to live implementation within a four-month period, resulting in the LIS-Interlink software product. Test results are retrieved at regular intervals from the BioLinkTM LIS (Laboratory Information System), encrypted and transferred to a secure area on the Web server. The primary health-care centres dial into the Internet using a local-cell service provided by Polish Telecom (TP), obtain a TCP/IP address using the TP DHCP server, and perform HTTP ‘get’ and ‘post’ operations to obtain the files by secure handshaking. The data are then automatically inserted into a local SQL database (with optional printing of incoming reports)for cumulative reporting and searching functions. The local database is fully multi-user and can be accessed from different clinics within the centres by a variety of networking protocols.  相似文献   
9.
Results of a survey of 74 college counseling center directors suggest that the centers are generally staffed by younger counseling psychologists who were attracted by the opportunity to counsel, the flexibility of activities afforded, and the chance to stay in an academic setting. More money, greater opportunity for advancement, and more desirable job activities are major reasons for leaving counseling center work. Full-time academic positions, for those at large centers, and private practice, for those at small centers, predominate as alternatives chosen. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
C60 fullerides are uniquely flexible molecular materials that exhibit a rich variety of behaviour, including superconductivity and magnetism in bulk compounds, novel electronic and orientational phases in thin films and quantum transport in a single-C60 transistor. The complexity of fulleride properties stems from the existence of many competing interactions, such as electron-electron correlations, electron-vibration coupling and intermolecular hopping. The exact role of each interaction is controversial owing to the difficulty of experimentally isolating the effects of a single interaction in the intricate fulleride materials. Here, we report a unique level of control of the material properties of K(x)C60 ultrathin films through well-controlled atomic layer indexing and accurate doping concentrations. Using scanning tunnelling microscope techniques, we observe a series of electronic and structural phase transitions as the fullerides evolve from two-dimensional monolayers to quasi-three-dimensional multilayers in the early stages of layer-by-layer growth. These results demonstrate the systematic evolution of fulleride electronic structure and molecular ordering with variable K(x)C60 film layer index, and provide essential information for the development of new molecular structures and devices.  相似文献   
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