scholarly journals Environmentally responsive polymeric "intelligent" materials: the ideal components of non-mechanical valves that control flow in microfluidic systems

2010 ◽  
Vol 27 (1) ◽  
pp. 1-14 ◽  
Author(s):  
J. Ruben Morones-Ramirez
Keyword(s):  
Control Flow ◽  
Microfluidic Systems ◽  
Intelligent Materials ◽  
Mechanical Valves ◽  
Environmentally Responsive ◽  
The Ideal

scholarly journals Research Methods And Experiments of Piezoelectric Plates

2020 ◽  
Vol 318 ◽  
pp. 01047
Author(s):  
Andrzej Wróbel
Keyword(s):  
Intelligent Systems ◽  
Piezoelectric Materials ◽  
Computational Cost ◽  
Intelligent Materials ◽  
Active Vibration Damping ◽  
Active Vibration ◽  
Electrical Part ◽  
Mathematical Equations ◽  
The Ideal ◽  
Piezoelectric Plates

The correct design of technical systems requires consideration of both geometrical and material parameters not only of the mechanical part, but also of the electrical part of the system. The correct assessment of characteristics and testing of intelligent systems should be carried out by both theoretical analyzes and laboratory tests. Usually this description is by means of mathematical equations. The ideal solution is in which it is possible to refine the object in such a way that the obtained model is the most accurate, and even the same as the physical model. Considering the complexity of the model, computational cost, computational possibilities and time-consuming calculations would practically prevent the use of this model. Intelligent materials are more often used for active vibration damping. They can be defined as a group of materials that have the ability to change their physical properties in an appropriate way as a result of external influences. One of the most popular materials in this group are piezoelectric materials. They are used where it is necessary to reduce vibrations with small amplitudes of μm and work in high frequency ranges. In the presented article, the author will attempt to refine the model of intelligent materials with particular emphasis on piezoelectric plates.

Control-flow analysis of procedural skills competencies in medical training through process mining

2019 ◽  
Vol 96 (1135) ◽  
pp. 250-256 ◽  
Author(s):  
Rene de la Fuente ◽  
Ricardo Fuentes ◽  
Jorge Munoz-Gama ◽  
Arnoldo Riquelme ◽  
Fernando R. Altermatt ◽  
...  
Keyword(s):  
Process Model ◽  
Medical Training ◽  
Process Mining ◽  
Flow Analysis ◽  
Control Flow ◽  
Ideal Model ◽  
Procedural Skills ◽  
Procedural Training ◽  
The Ideal ◽  
Control Flow Analysis

BackgroundProcedural skills are key to good clinical results, and training in them involves a significant amount of resources. Control-flow analysis (ie, the order in which a process is performed) can provide new information for those who train and plan procedural training. This study outlines the steps required for control-flow analysis using process mining techniques in training in an ultrasound-guided internal jugular central venous catheter placement using a simulation.MethodsA reference process model was defined through a Delphi study, and execution data (event logs) were collected from video recordings from pretraining (PRE), post-training (POST) and expert (EXP) procedure executions. The analysis was performed to outline differences between the model and executions. We analysed rework (activity repetition), alignment-based fitness (conformance with the ideal model) and trace alignment analysis (visual ordering pattern similarities).ResultsExpert executions do not present repetition of activities (rework). The POST rework is lower than the PRE, concentrated in the steps of the venous puncture and guidewire placement. The adjustment to the ideal model measure as alignment-based fitness, expressed as a median (25th–75th percentile) of PRE 0.74 (0.68–0.78) is less than POST 0.82 (0.76–0.86) and EXP 0.87 (0.82–0.87). There are no significant differences between POST and EXP. The graphic analysis of alignment and executions shows a progressive increase in order from PRE to EXP executions.ConclusionProcess mining analysis is able to pinpoint more difficult steps, assess the concordance between reference mode and executions, and identify control-flow patterns in procedural training courses.

Recellularization Potential of Acellular Aortic Valve Scaffolds Treated With Collagenase and Acetic Acid

2009 ◽  
Author(s):  
Benjamin C. Weed ◽  
Ali Borazjani ◽  
Scott Metzler ◽  
Filip To ◽  
James Warnock ◽  
...  
Keyword(s):  
Aortic Valve ◽  
Aortic Valve Disease ◽  
Heart Surgery ◽  
Open Heart Surgery ◽  
Common Type ◽  
The Third ◽  
Mechanical Valves ◽  
Blood Clots ◽  
Over Time ◽  
The Ideal

It is estimated that five million Americans suffer from moderate to severe aortic valve disease, making it the third most common type of cardiovascular disease. Aortic valve replacement, which is second leading reason for undergoing open heart surgery, is the prevailing treatment for patients with extensive aortic valve pathologies. Currently, substitute valves used to replace the disease valves are classified as either mechanical or biological, each of which carry significant disadvantages. Patients with mechanical valves are at a much higher risk for developing blood clots and therefore must remain on anticoagulants for the remainder of their lifetime; and biological valves, which are typically derived from porcine or cadeveric tissues, will deteriorate over time. The ideal replacement valve is one that presents no thrombogenicity or immunogenecity, provides normal hemodynamics, is free of blood damaging elements, offers a practical mode for implantation, is able to grow and remodel, and does not deteriorate over time.

Localization of Intracellular Antigens in thin Sections with Ferritin Labeled Antibody

1970 ◽  
Vol 28 ◽  
pp. 174-175
Author(s):  
M.S. Shahrabadi ◽  
T. Yamamoto
Keyword(s):  
Bovine Serum Albumin ◽  
Bovine Serum ◽  
Antigenic Determinants ◽  
Conjugate Prior ◽  
Thin Sections ◽  
Specific Attachment ◽  
Intracellular Antigen ◽  
Antigen Antibody ◽  
Ideal Method ◽  
The Ideal

The technique of labeling of macromolecules with ferritin conjugated antibody has been successfully used for extracellular antigen by means of staining the specimen with conjugate prior to fixation and embedding. However, the ideal method to determine the location of intracellular antigen would be to do the antigen-antibody reaction in thin sections. This technique contains inherent problems such as the destruction of antigenic determinants during fixation or embedding and the non-specific attachment of conjugate to the embedding media. Certain embedding media such as polyampholytes (2) or cross-linked bovine serum albumin (3) have been introduced to overcome some of these problems.

Criteria and Methods for Reliable Three-Dimensional Image Reconstruction

1974 ◽  
Vol 32 ◽  
pp. 330-331
Author(s):  
R. A. Crowther
Keyword(s):  
Image Reconstruction ◽  
Finite Number ◽  
Density Distribution ◽  
Electron Micrographs ◽  
Mathematical Problem ◽  
Three Dimensional ◽  
Ideal Case ◽  
Dimensional Image ◽  
General Object ◽  
The Ideal

The reconstruction of a three-dimensional image of a specimen from a set of electron micrographs reduces, under certain assumptions about the imaging process in the microscope, to the mathematical problem of reconstructing a density distribution from a set of its plane projections.In the absence of noise we can formulate a purely geometrical criterion, which, for a general object, fixes the resolution attainable from a given finite number of views in terms of the size of the object. For simplicity we take the ideal case of projections collected by a series of m equally spaced tilts about a single axis.

X-Ray Analysis of Frozen Hydrated Sections:The Unconventional Approach

1982 ◽  
Vol 40 ◽  
pp. 754-757
Author(s):  
R. Beeuwkes ◽  
A. Saubermann ◽  
P. Echlin ◽  
S. Churchill
Keyword(s):  
Ratio Method ◽  
Frozen Sections ◽  
Technical Problems ◽  
Sample Handling ◽  
X Ray ◽  
Common Group ◽  
Ideal Method ◽  
Classic Paper ◽  
Physical Principles ◽  
The Ideal

Fifteen years ago, Hall described clearly the advantages of the thin section approach to biological x-ray microanalysis, and described clearly the ratio method for quantitive analysis in such preparations. In this now classic paper, he also made it clear that the ideal method of sample preparation would involve only freezing and sectioning at low temperature. Subsequently, Hall and his coworkers, as well as others, have applied themselves to the task of direct x-ray microanalysis of frozen sections. To achieve this goal, different methodological approachs have been developed as different groups sought solutions to a common group of technical problems. This report describes some of these problems and indicates the specific approaches and procedures developed by our group in order to overcome them. We acknowledge that the techniques evolved by our group are quite different from earlier approaches to cryomicrotomy and sample handling, hence the title of our paper. However, such departures from tradition have been based upon our attempt to apply basic physical principles to the processes involved. We feel we have demonstrated that such a break with tradition has valuable consequences.

High Resolution Study of Polytypism: Application to SiC and Au3 Mn

1982 ◽  
Vol 40 ◽  
pp. 540-541
Author(s):  
G. Van Tendeloo ◽  
J. Van Landuyt ◽  
S. Amelinckx
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Stacking Sequence ◽  
X Ray ◽  
Powerful Technique ◽  
Resolution Study ◽  
The Ideal

Polytypism has been studied for a number of years and a wide variety of stacking sequences has been detected and analysed. SiC is the prototype material in this respect; see e.g. Electron microscopy under high resolution conditions when combined with x-ray measurements is a very powerful technique to elucidate the correct stacking sequence or to study polytype transformations and deviations from the ideal stacking sequence.

Possible applications of fraunhofer holography in high resolution electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 222-223 ◽  
Author(s):  
N. Bonnet ◽  
M. Troyon ◽  
P. Gallion
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Transfer Function ◽  
Radiation Damage ◽  
High Resolution Electron Microscopy ◽  
Far Field ◽  
Field Region ◽  
Crystalline Materials ◽  
Resolution Electron ◽  
The Ideal

Two main problems in high resolution electron microscopy are first, the existence of gaps in the transfer function, and then the difficulty to find complex amplitude of the diffracted wawe from registered intensity. The solution of this second problem is in most cases only intended by the realization of several micrographs in different conditions (defocusing distance, illuminating angle, complementary objective apertures…) which can lead to severe problems of contamination or radiation damage for certain specimens.Fraunhofer holography can in principle solve both problems stated above (1,2). The microscope objective is strongly defocused (far-field region) so that the two diffracted beams do not interfere. The ideal transfer function after reconstruction is then unity and the twin image do not overlap on the reconstructed one.We show some applications of the method and results of preliminary tests.Possible application to the study of cavitiesSmall voids (or gas-filled bubbles) created by irradiation in crystalline materials can be observed near the Scherzer focus, but it is then difficult to extract other informations than the approximated size.

The DQE of an electron image recording system

1978 ◽  
Vol 36 (1) ◽  
pp. 100-101
Author(s):  
K.-H. Herrmann ◽  
D. Krahl ◽  
H.-P Rust
Keyword(s):  
Primary Electron ◽  
Ideal Case ◽  
Image Recording ◽  
Main Requirement ◽  
High Detection ◽  
Electron Image ◽  
Video Amplifier ◽  
Detection Quantum Efficiency ◽  
Selection Of ◽  
The Ideal

The high detection quantum efficiency (DQE) is the main requirement for an imagerecording system used in electron microscopy of radiation-sensitive specimens. An electronic TV system of the type shown in Fig. 1 fulfills these conditions and can be used for either analog or digital image storage and processing [1], Several sources of noise may reduce the DQE, and therefore a careful selection of various elements is imperative.The noise of target and of video amplifier can be neglected when the converter stages produce sufficient target electrons per incident primary electron. The required gain depends on the type of the tube and also on the type of the signal processing chosen. For EBS tubes, for example, it exceeds 10. The ideal case, in which all impinging electrons create uniform charge peaks at the target, is not obtainable for several reasons, and these will be discussed as they relate to a system with a scintillator, fiber-optic and photo-cathode combination as the first stage.

New type electron gun with electrostatic and electromagnetic lenses

1978 ◽  
Vol 36 (1) ◽  
pp. 62-63
Author(s):  
T. Ichinokawa ◽  
H. Maeda
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Optimum Condition ◽  
Bias Voltage ◽  
Electron Gun ◽  
Charge Effect ◽  
Micro Fabrication ◽  
Maximum Brightness ◽  
New Type ◽  
The Ideal

I. IntroductionThermionic electron gun with the Wehnelt grid is popularly used in the electron microscopy and electron beam micro-fabrication. It is well known that this gun could get the ideal brightness caluculated from the Lengumier and Richardson equations under the optimum condition. However, the design and ajustment to the optimum condition is not so easy. The gun has following properties with respect to the Wehnelt bias; (1) The maximum brightness is got only in the optimum bias. (2) In the larger bias than the optimum, the brightness decreases with increasing the bias voltage on account of the space charge effect. (3) In the smaller bias than the optimum, the brightness decreases with bias voltage on account of spreading of the cross over spot due to the aberrations of the electrostatic immersion lens.In the present experiment, a new type electron gun with the electrostatic and electromagnetic lens is designed, and its properties are examined experimentally.

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