Auxiliary telegraphy     

I. Kitsee 《Journal of The Franklin Institute》1897,143(1):68-73

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Offer of a new and improved plan of constructing iron rail-ways and carriages,by which all sorts of goods,merchandise and other articles whatever,as likewise passengers,will be conveyed with much greater ease,convenience, and speed,and with less expense than could till now be effected,by employing either the power of steam or that of horses     

I.L. Pouchee 《Journal of The Franklin Institute》1828,6(5):355-359

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The work of the teacher in grades 2–4 at primary schools     

V. I. Pomagaiba 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1964,10(3):333-341

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The nature of a developer sludge     

J.I. Crabtree 《Journal of The Franklin Institute》1918,186(3):371-372

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Interview with Roald Dahl     

Mark I. West 《Children‘s Literature in Education》1990,21(2):61-66

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The study of systems and methods for scientometric analysis of scientific publications     

A. V. Shvets  D. A. Devyatkin  I. V. Smirnov  I. A. Tikhomirov  K. V. Popov  K. N. Yarygin 《Scientific and Technical Information Processing》2015,42(5):359-366

This paper provides an overview of the methods and systems that are applied for scientometric analysis of scientific publications. Methods to identify promising research directions are described. The results of an experimental study aimed at determining the directions of scientific research within the subject area of “regenerative medicine” by using various methods are presented. Conclusions are made about the prospects and shortcomings of the applied methods. Directions for further research are proposed.  相似文献   

The use of economic classifiers for the indexing of scientific publications     

K. I. Belousov  D. A. Baranov  N. L. Zelyanskaya  T. V. Karlina 《Scientific and Technical Information Processing》2015,42(4):299-305

The experience from the application of the OKVED 2 economic classifier for indexing scientific publications is considered. More than 9500 articles on the subject of “Automation. Computer Engineering” in authoritative Russian magazines were the material for the study. Some means for the comparative analysis of economic statistics and results of the classification of scientific publications are shown.  相似文献   

Enhanced single-cell printing by acoustophoretic cell focusing     

I. Leibacher  J. Schoendube  J. Dual  R. Zengerle  P. Koltay 《Biomicrofluidics》2015,9(2)

Recent years have witnessed a strong trend towards analysis of single-cells. To access and handle single-cells, many new tools are needed and have partly been developed. Here, we present an improved version of a single-cell printer which is able to deliver individual single cells and beads encapsulated in free-flying picoliter droplets at a single-bead efficiency of 96% and with a throughput of more than 10 beads per minute. By integration of acoustophoretic focusing, the cells could be focused in x and y direction. This way, the cells were lined-up in front of a 40 μm nozzle, where they were analyzed individually by an optical system prior to printing. In agreement with acoustic simulations, the focusing of 10 μm beads and Raji cells has been achieved with an efficiency of 99% (beads) and 86% (Raji cells) to a 40 μm wide center region in the 1 mm wide microfluidic channel. This enabled improved optical analysis and reduced bead losses. The loss of beads that ended up in the waste (because printing them as single beads arrangements could not be ensured) was reduced from 52% ± 6% to 28% ± 1%. The piezoelectric transducer employed for cell focusing could be positioned on an outer part of the device, which proves the acoustophoretic focusing to be versatile and adaptable.  相似文献   

Disrupting the wall accumulation of human sperm cells by artificial corrugation     

H. A. Guidobaldi  Y. Jeyaram  C. A. Condat  M. Oviedo  I. Berdakin  V. V. Moshchalkov  L. C. Giojalas  A. V. Silhanek  V. I. Marconi 《Biomicrofluidics》2015,9(2)

Many self-propelled microorganisms are attracted to surfaces. This makes their dynamics in restricted geometries very different from that observed in the bulk. Swimming along walls is beneficial for directing and sorting cells, but may be detrimental if homogeneous populations are desired, such as in counting microchambers. In this work, we characterize the motion of human sperm cells ∼60 μm long, strongly confined to ∼25 μm shallow chambers. We investigate the nature of the cell trajectories between the confining surfaces and their accumulation near the borders. Observed cell trajectories are composed of a succession of quasi-circular and quasi-linear segments. This suggests that the cells follow a path of intermittent trappings near the top and bottom surfaces separated by stretches of quasi-free motion in between the two surfaces, as confirmed by depth resolved confocal microscopy studies. We show that the introduction of artificial petal-shaped corrugation in the lateral boundaries removes the tendency of cells to accumulate near the borders, an effect which we hypothesize may be valuable for microfluidic applications in biomedicine.  相似文献   

Microfluidic sampling system for tissue analytics     

A. Hokkanen  I. Stuns  P. Schmid  A. Kokkonen  F. Gao  A. Steinecker  J. Budczies  P. Heimala  L. Hakalahti 《Biomicrofluidics》2015,9(5)

We have developed a microfluidics based sampling system for tissue analytics. The proof-of-concept of the sampling system was demonstrated by extracting lipid samples from tissue biopsies. The sample collection system consists of a disposable silicon based multiport microneedle integrated with polymer microfluidics. The polymethyl methacrylate polymer microfluidic chip has a 10 μl sample reservoir and actuation membranes for liquid pumping. A special automated robotic system was developed to control the positioning of the needle and the sampling procedure on preselected spots on the tissue. Real breast cancer tissue samples were used to test the feasibility of the sampling system. We successfully measured indicative cancer biomarkers from the tissue surface. Phosphatidylcholine and phosphoethanolamine were extracted from the tissue membrane with methyl tert-butyl ether solvent and detected by mass spectrometry. In the future, this tool could be used in characterization of preoperative biopsies and tumour tissues removed during surgery.  相似文献