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81.
The extraordinary romance and thrilling adventure associated with the tale of wootz steel shows how Indian metallurgists were the world leaders in antiquity in the manufacture of this legendary high-grade steel. In many ways this material was brought to global attention by the writings of Cyril Stanley Smith. Modern metallurgy and materials science rest on the foundation built by the study of this steel during the past three centuries.  相似文献   
82.
Orthographic spelling is a major difficulty in German-speaking children with dyslexia. The aim of the present study was to evaluate the effectiveness of an orthographic spelling training in spelling-disabled students (grade 5 and 6). In study 1, ten children (treatment group) received 15 individually administered weekly intervention sessions (60 min each). A control group (n = 4) did not receive any intervention. In study 2, orthographic spelling training was provided to a larger sample consisting of a treatment group (n = 13) and a delayed treatment control group (n = 14). The main criterion of spelling improvement was analyzed using an integrated dataset from both studies. Repeated-measures analysis of variance revealed that gains in spelling were significantly greater in the treatment group than in the control group. Statistical analyses also showed significant improvements in reading (study 1) and in a measure of participants’ knowledge of orthographic spelling rules (study 2). The findings indicate that an orthographic spelling training enhances reading and spelling ability as well as orthographic knowledge in spelling-disabled children learning to spell a transparent language like German.  相似文献   
83.
Luciano Floridi argues that every existing entity is deserving of at least minimal moral respect in virtue of having intrinsic value qua information object. In this essay, I attempt a comprehensive assessment of this important view as well as the arguments Floridi offers in support of it. I conclude both that the arguments are insufficient and that the thesis itself is substantively implausible from the standpoint of ordinary intuitions.  相似文献   
84.
Acoustic trapping of minute bead amounts against fluid flow allows for easy automation of multiple assay steps, using a convenient aspirate/dispense format. Here, a method based on acoustic trapping that allows sample preparation for immuno-matrix-assisted laser desorption/ionization mass spectrometry using only half a million 2.8 μm antibody covered beads is presented. The acoustic trapping is done in 200 × 2000 μm2 glass capillaries and provides highly efficient binding and washing conditions, as shown by complete removal of detergents and sample processing times of 5-10 min. The versatility of the method is demonstrated using an antibody against Angiotensin I (Ang I), a peptide hormone involved in hypotension. Using this model system, the acoustic trapping was efficient in enriching Angiotensin at 400 pM spiked in plasma samples.  相似文献   
85.

Introduction:

There are a number of pre-analytical and analytical factors, which cause false results in the complete blood count. The present case identifies cold agglutinins as the cause for the mismatch between hematocrit and hemoglobin values.

Materials and methods:

70-year old female patient had a history of cerebrovascular diseases and rheumatoid arthritis. During routine laboratory examination, the patient had normal leukocyte and platelet counts; however, the hemoglobin (Hb: 105 g/L) and hematocrit (HCT: 0.214 L/L) results were discordant. Hemolysis, lipemia and cold agglutinin were evaluated as possible reasons for the mismatch between hematocrit and hemoglobin values.

Results:

First blood sample was slightly hemolysed. Redrawn sample without hemolysis or lipemia was analyzed but the mismatch became even more distinct (Hb: 104 g/L and HCT: 0.08 L/L). In this sample, the titration of the cold agglutinin was determined and found to be positive at 1:64 dilution ratios. After an incubation of the sample at 37°C for 2 hours, reversibility of agglutination was observed.

Conclusion:

We conclude that cold agglutinins may interfere with the analysis of erythrocyte and erythrocyte-related parameters (HCT, MCV, MCH and MCHC); however, Hb, leukocyte and platelet counts are not affected.  相似文献   
86.
A seven channel polystyrene (PS) microchip has been constructed using a micromilling machine and a high-temperature assembling. Protein A (PA) has been immobilized by a passive sorption on the microchannel walls. Two bioaffinity assays with human immunoglobulin G (hIgG) as a ligand have been carried out. (i) PA as the receptor and fluorescently labeled hIgG (FITC-hIgG) as the ligand, (ii) PA as the receptor with hIgG as the quantified ligand and fluorescently labeled goat anti-human IgG (FITC-gIgG) as the secondary ligand. One incubation step of the assays took only 5 min instead of hours typical for enzyme-linked immunosorbent assay applications. Calibration curves of the dependence of a fluorescence signal on the hIgG concentration in a sample have been obtained in one step due to a parallel arrangement of microchannels. A mathematical model of the PA-FITC-hIgG complex formation in the chip has been developed. The values of the kinetic constant of the PA-FITC-hIgG binding (kon=5.5 m3 mol−1 s−1) and the equilibrium dissociation constant of the formed complex (Kd≤3×10−6 mol m−3) have been obtained by fitting to experimental data. The proposed microchip enables fast evaluation of kinetic and equilibrium constants of ligand-receptor bioaffinity pairs and the ligand quantification. As the use of microfluidic chips for immunoassays is often limited by price, we used procedures and chemicals that allow for an inexpensive construction and operation of the microdevice, e.g., temperature assembling as a fabrication technique, detection via an ordinary digital camera, nonspecific polystyrene as a substrate, passive sorption of biomolecules as an immobilization technique, etc.  相似文献   
87.

Introduction

Hemolysis can occur during sample collection, handling and transport. It is more frequent when the non-laboratory staff performs sampling. The aim of this study was to assess nurses’ knowledge on the causes of hemolysis and consequential impact on the laboratory tests results. Additionally, the differences in knowledge, related to work experience, professional degree and previous education about hemolysis were explored.

Materials and methods

An anonymus survey, containing 11 questions on demographics, causes of hemolysis, its impact on biochemical parameters and nurses’ attitude towards additional education in preanalytics, was conducted in four Croatian hospitals. The answers were compared by Chi-squared and Fischer exact test.

Results

In total, 562 survey results were collected. Majority of nurses declared familiarity with the term “hemolysis” (99.6%). There were 77% of correct answers regarding questions about the causes of hemolysis, but only 50% when it comes to questions about interference in biochemical tests. The percentage of correct answers about causes was significantly lower (P = 0.029) among more experienced nurses, and higher (P = 0.027) in those with higher professional degree, while influence of previous education was not significant. Also, higher percentage of correct answers about interferences was encountered in nurses with longer work experience (P = 0.039). More than 70% of nurses declared that additional education about preanalytical factors would be beneficial.

Conclusion

Croatian nurses are familiar with the definition of hemolysis, but a lack of knowledge about causes and influence on laboratory test results is evident. Nurses are eager to improve their knowledge in this field of preanalytical phase.Key words: hemolysis, nurses, survey, preanalytical phase  相似文献   
88.
Intellectual capital (IC), leading to sustainable competitiveness shapes the patterns of business reality nowadays. IC disclosure has become a critical necessity in this new framework. Being a novel interdisciplinary study, the aim of this paper was to examine IC disclosure by Greek publicly traded firms implementing association and decision rules. Firms were divided into three classes (low, medium and high) according to their IC disclosure, measured by the content analysis methodology. The association rules of each class were specified, highlighting IC reporting profile and focus of the firms belonging to each class. Firms in the high class were shown to have strongly realised the crucial need for a reporting change. Teamwork, corporate culture and extra-firm potential appeared to be underlined. Applying the decision tree methodology, the paper succeeded in proving the remuneration–incentive system, R&D and business collaborations items as the IC reporting-related factors differentiating classes.  相似文献   
89.
In this paper, social network analysis techniques and regression models are used to explain the impact of the level of knowledge development on ego-network redundancy in a community of hospital physicians. Our findings document that the level of knowledge development and the extent to which knowledge is homogeneously distributed amongst collaborating physicians are related to the redundancy of their advice networks, albeit with opposite effects. Our results highlight also that the impact of these relationships on network redundancy is moderated based on whether partnering individuals belong to different professional groups. Our results provide valuable input for the management of knowledge networks within professional organizations.  相似文献   
90.
Despite the large volume of research and managerial literature on knowledge management, many practitioners seem to find it difficult to appreciate its added value for their managerial work. This paper aims to understand and elaborate the added value that knowledge management as a managerial approach can bring to the management of knowledge-intensive organizations. This study explores empirically the actual management practices of a knowledge-intensive organization and examines how knowledge-related phenomena are managed as embedded aspects of management. This paper makes a contribution to prior discussions concerning the relevance of knowledge management and the role of knowledge management as an embedded management practice. The findings of this study should be useful in explaining practitioners the nature, relevance and value of knowledge management.  相似文献   
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