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101.
Today all parties within the health-care system demand more information and evidence to take more efficient and pinpointed management decisions. Their goal is a better patient and patient-care management. This paper presents an information visualisation approach to discover knowledge for the management of tele-home care for the elderly using the video-telephone: what type of elderly need what type of video-telephone interventions? This document focuses on the synthesis aspects of data mining with a view to knowledge discovery: the global, holistic, synthesis approach. More specifically, it summarises visually the relationships among the types of video-telephony care, among the segments of elderly, and between the types of interventions and the segments of elderly simultaneously. The graphical display allows delineating areas that group elderly with a similar/dissimilar video-telephony care profile. Information visualisation is a promising approach to provide insight into large multidimensional data sets. It fosters knowledge discovery.  相似文献   
102.
The 2015 Paris Agreement to keep global warming well below 2℃above pre-industrial levels and aim towards limiting warming to 1.5℃marked a wa-tershed in planetar...  相似文献   
103.
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   
104.
105.
Most research focuses on preschoolers’ primary non-parental child care arrangement despite evidence that multiple arrangements are relatively common. Using the nationally-representative Early Childhood Longitudinal Study, Birth Cohort, we compare characteristics and outcomes of families whose 4-year olds attend both home- and center-based child care with those who attend either home- or center-based care exclusively or receive no non-parental care at all. We find that about one fifth of 4-year olds attend both home- and center-based child care. Mothers’ priorities for care (getting their child ready for school, matching their families’ cultural background) and perceptions of good local care options predict their combining home- and center-based care. Preschoolers score higher on reading and math assessments, on average, when they attend centers, alone or in combination with home-based child care, than when they are cared for only in homes, either by their parents or by others. Preschoolers’ average socioemotional outcomes generally do not differ between families who do and who do not combine care types. Implications for research and policy are discussed.  相似文献   
106.
The need for supporting student writing has received much attention in writing research. One specific type of support is feedback—including peer feedback—on the writing process. Despite the wealth of literature on both feedback and academic writing, there is little empirical evidence on what type of feedback best promotes writing in online environments. This article reports on research that tries to determine what type of feedback best improves the quality of collaborative writing and what the effects of feedback are on student learning in an environment based on asynchronous written communication. The results reveal that concerning the type of feedback, epistemic feedback or epistemic and suggestive feedback best improve the quality of collaborative writing performance. The nature of the feedback-giver (whether teacher feedback or teacher and peer) makes a difference to the final text only when the feedback is epistemic, or epistemic and suggestive.  相似文献   
107.
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   
108.

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   
109.
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   
110.

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   
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