A stokes polarimetric light microscopy view of liquid crystal droplets

AbstractThe optical characteristics of materials, such as their magnetooptical effects, birefringence, optical activities, linear and circular dichroism, are probed via the polarisation states of light transmitted through or reflected from the specimens. As such, the measurements of the polarisation states play an important role in many research disciplines. Experimentally, Stokes parameters provide a full description of the polarisation states of light. We report the implementation of a dual- photoelastic modulator based polarimeter in a light microscope, enabling the determination of Stokes parameters at each pixel. As a case study, polarimetric images of liquid crystal droplets of different internal structures are obtained, showing their distinct polarisation characteristics. We demonstrate that the prototype Stokes polarimetric microscope allows the quantitative determination of the polarisation characteristics of light at the object plane and enables the access of the information of full polarisation states as compared to a conventional cross polariser microscope. This work shows that Stokes polarimetric microscopy may find potential applications in a wide range of research fields.

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Designing Sustainability Curricula

Curriculum Design and Classroom Management ◽

10.4018/978-1-4666-8246-7.ch040 ◽

2015 ◽

pp. 724-743 ◽

Cited By ~ 1

Author(s):

Madoc Sheehan

Keyword(s):

Chemical Engineering ◽

Cognitive Learning ◽

Design Tool ◽

Degree Programs ◽

James Cook ◽

Engineering Program ◽

Engineering Degree ◽

Wide Range

Developing an engineering student's awareness of sustainability through the embedding of sustainability curricula is widely considered to be essential to modernising chemical engineering degree programs. In this chapter, the chemical engineering program at James Cook University is used as a case study to illustrate the design and sequencing of embedded curricula associated with developing a students' awareness of sustainability. There are a wide range of examples of skills, techniques, and characteristics associated with developing this awareness. In this chapter, an approach is described whereby a set of generic and interdisciplinary capabilities are developed to provide a degree of flexibility in how sustainability is interpreted and taught. A cognitive learning matrix is utilised as a design tool that facilitates determination of new subject learning outcomes aligned with the sustainability capabilities. A variety of curriculum examples are introduced and described.

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CRSP, numerical results for an electrical resistivity array to detect underground cavities

Open Geosciences ◽

10.1515/geo-2017-0002 ◽

2017 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Amin Amini ◽

Hamidreza Ramazi

Keyword(s):

Electrical Resistivity ◽

Geophysical Methods ◽

Electrode Array ◽

Electrode Configuration ◽

Electrode Arrays ◽

Wide Range ◽

Underground Cavities ◽

Conventional Electrode

AbstractThis paper is devoted to the application of the Combined Resistivity Sounding and Profiling electrode configuration (CRSP) to detect underground cavities. Electrical resistivity surveying is among the most favorite geophysical methods due to its nondestructive and economical properties in a wide range of geosciences. Several types of the electrode arrays are applied to detect different certain objectives. In one hand, the electrode array plays an important role in determination of output resolution and depth of investigations in all resistivity surveys. On the other hand, they have their own merits and demerits in terms of depth of investigations, signal strength, and sensitivity to resistivity variations. In this article several synthetic models, simulating different conditions of cavity occurrence, were used to examine the responses of some conventional electrode arrays and also CRSP array. The results showed that CRSP electrode configuration can detect the desired objectives with a higher resolution rather than some other types of arrays. Also a field case study was discussed in which electrical resistivity approach was conducted in Abshenasan expressway (Tehran, Iran) U-turn bridge site for detecting potential cavities and/or filling loose materials. The results led to detect an aqueduct tunnel passing beneath the study area.

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Determination of Birefringence by Measuring the Stokes Parameters in a C$_{60}$ Fullerene-doped Nematic Liquid Crystal

New Physics Sae Mulli ◽

10.3938/npsm.66.216 ◽

2016 ◽

Vol 66 (2) ◽

pp. 216-222

Author(s):

Gi Hyeok LEE ◽

Gun Yeup KIM ◽

Chong Hoon KWAK*

Keyword(s):

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Stokes Parameters

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Development of Methods for the Determination of pKa Values

Analytical Chemistry Insights ◽

10.4137/aci.s12304 ◽

2013 ◽

Vol 8 ◽

pp. ACI.S12304 ◽

Cited By ~ 152

Author(s):

Jetse Reijenga ◽

Arno van Hoof ◽

Antonie van Loon ◽

Bram Teunissen

Keyword(s):

Dissociation Constant ◽

Conceptual Development ◽

Acid Dissociation ◽

Acid Dissociation Constant ◽

Future Developments ◽

Research Fields ◽

Current State ◽

Wide Range ◽

Pka Determination

The acid dissociation constant (pKa) is among the most frequently used physicochemical parameters, and its determination is of interest to a wide range of research fields. We present a brief introduction on the conceptual development of pKa as a physical parameter and its relationship to the concept of the pH of a solution. This is followed by a general summary of the historical development and current state of the techniques of pKa determination and an attempt to develop insight into future developments. Fourteen methods of determining the acid dissociation constant are placed in context and are critically evaluated to make a fair comparison and to determine their applications in modern chemistry. Additionally, we have studied these techniques in light of present trends in science and technology and attempt to determine how these trends might affect future developments in the field.

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Implementación electrónica del oscilador caótico de Rӧssler

Revista de Energía Química y Física ◽

10.35429/jcpe.2020.22.7.18.25 ◽

2020 ◽

pp. 18-25

Author(s):

Alejandro Silva-Juárez ◽

Jaime Estevez-Carreón ◽

Juan Jorge Ponce-Mellado ◽

Gustavo Herrera-Sánchez

Keyword(s):

Secure Communication ◽

Communication Systems ◽

Structural Damage ◽

Random Number Generators ◽

Analog Electronics ◽

Potential Applications ◽

The Stability ◽

Electronic Implementation

Chaotic systems have attracted the attention of the scientific community due to their potential applications in many branches of science and engineering, chaos theory is used in cryptography, in the creation of population models in biology, studying turbulence in mechanics of fluids, in economics it is used to predict the behavior of the stock market, in astronomy it is used to describe the motion of many planetary bodies, to improve the prediction of trajectories in asteroids and to determine whether or not they come into contact with the earth, in More recent years have been applied in the prediction and / or control of the dynamics of the human brain, a large number of works have been reported in different areas in order to address some interesting problems, such as the determination of structural damage in materials or in secure communication systems. In this work the implementation of chaotic oscillators in analog electronics is addressed, the case study of the autonomous non-linear dynamic system of Rӧssler is presented, the stability analysis of the system is developed, analytical, numerical and experimental results are included, as well as its Electronic implementation measured under laboratory conditions to observe experimental chaotic attractors, which will be used in the implementation of random number generators and secure communication systems for image encryption.

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A Portable and Automated Postural Perturbation System for Balance Assessment, Training, and Neuromuscular System Identification

Journal of Medical Devices ◽

10.1115/1.3026558 ◽

2008 ◽

Vol 2 (4) ◽

Cited By ~ 9

Author(s):

Albert H. Vette ◽

Egor Sanin ◽

Abdulkadir Bulsen ◽

Alan Morris ◽

Kei Masani ◽

...

Keyword(s):

Treadmill Walking ◽

Displacement Velocity ◽

Postural Perturbation ◽

Peak Displacement ◽

Highly Sensitive ◽

Wide Range ◽

Potential Applications ◽

Postural Perturbations ◽

Accuracy And Repeatability

To date, a postural perturbation system capable of generating position-, velocity-, and force-controlled perturbations while being portable and suitable for use during various postural scenarios does not exist. Therefore, the purpose of the present study was to design, develop, and test a portable and automated postural perturbation system (PAPPS) that can be used to measure and train postural reactions during sitting, standing, and treadmill walking. The core component of the PAPPS was a linear actuator that provides horizontal perturbations. The actuator could generate arbitrary displacement, velocity, or force perturbations as a function of time. In addition, the PAPPS was able to measure the actuator’s displacement, velocity, and load, which could be used to study postural perturbation responses. The height at which the PAPPS was delivering the perturbations could be easily adjusted to allow for different subject/patient anthropometrics and a wide range of postural scenarios such as sitting, standing, and treadmill walking. The PAPPS generated a peak displacement of 0.6m, a peak velocity of 0.5m∕s, and a peak force of 600N, which is more than sufficient to elicit high intensity postural perturbations. Multiple and nested safety circuits have been implemented into the PAPPS to ensure the safety of the subjects/patients during experiments and/or training. To evaluate the accuracy and repeatability of the PAPPS during position-, velocity-, and force-controlled perturbations, experiments were conducted using sinusoidal, impulse, and ramp profiles as a function of time. Highly sensitive displacement and force sensors that were external to the PAPPS were used to determine the accuracy and repeatability of the proposed device. In addition, a case study was performed to demonstrate the performance of the PAPPS during pseudorandom sinusoidal perturbations that were applied to a healthy individual during sitting. The accuracy and repeatability tests suggest that the PAPPS can generate reliable and high-precision displacement, velocity, and force perturbations. Potential applications of this system include, but are not limited to (1) studies of postural response to various perturbation types and profiles in diverse subject populations during sitting, standing, and treadmill walking, and (2) training of postural balance in diverse patient populations during sitting, standing, and treadmill walking.

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Experimental determination of the Stokes parameters using a dual photoelastic modulator system

Applied Optics ◽

10.1364/ao.49.002644 ◽

2010 ◽

Vol 49 (14) ◽

pp. 2644 ◽

Cited By ~ 7

Author(s):

Wei Guan ◽

Paul J. Cook ◽

Grenville A. Jones ◽

Tiehan H. Shen

Keyword(s):

Experimental Determination ◽

Stokes Parameters ◽

Photoelastic Modulator

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Effect of Fe3O4 and TiO2 Nanoparticles on Catalase Activity and β-Carotene Content at Pigmented Yeast Strain Rhodotorula gracilis

Acta Universitatis Cibiniensis Series E Food Technology ◽

10.1515/aucft-2017-0004 ◽

2017 ◽

Vol 21 (1) ◽

pp. 35-40

Author(s):

Agafia Usatîi ◽

Alina Beșliu ◽

Nadejda Efremova

Keyword(s):

Catalase Activity ◽

Yeast Strain ◽

Carotene Content ◽

Wide Range ◽

Rhodotorula Gracilis ◽

Potential Applications ◽

First Time ◽

Antioxidant Enzyme Catalase ◽

Β Carotene

AbstractThe properties of nanoparticles have been used in a wide range of potential applications in food industry, medicine, microbial biotechnology, cosmetics, environmental production. Research results of evaluation of the effect of Fe3O4and TiO2nanoparticles applicated in large concentration limits on some parameters of pigmented yeast strainRhodotorula gracilisCNMN-Y-30 are presented in this paper. It was established that nanoparticles selected for study caused toxic effects on β-caroten accumulation and activity of antioxidant enzyme catalase depending on concentration and nanostructure. The strong correlation between concentration of nanoparticles and evaluated components has been revealed at studied yeast strain. Coefficients of correlation varied in limits R2= 0.623... 0.951. For the first time, the determination of β-carotene accumulation and catalase activity rate as functional tests for estimation of toxicity of nanoparticles for pigmented yeast strainRhodotorula graciliswas effectuated. Thus, it was established that adaptive response of yeast strain to the presence of Fe3O4and TiO2nanoparticles has been manifested by modification of the processes of β-carotene biosythesis and catalase activity.

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Looking Behind the Increase in Custodial Remand Populations

International Journal for Crime Justice and Social Democracy ◽

10.5204/ijcjsd.v2i2.84 ◽

2013 ◽

Vol 2 (2) ◽

pp. 80-99 ◽

Cited By ~ 10

Author(s):

David Brown

Keyword(s):

New South ◽

Individual Case ◽

Law Reform ◽

South Wales ◽

Wide Range ◽

Commission Report ◽

Key Drivers ◽

The Individual

Numbers, rates and proportions of those remanded in custody have increased significantly in recent decades across a range of jurisdictions. In Australia they have doubled since the early 1980s, such that close to one in four prisoners is currently unconvicted. Taking NSW as a case study and drawing on the recent New South Wales Law Reform Commission Report on Bail (2012), this article will identify the key drivers of this increase in NSW, predominantly a form of legislative hyperactivity involving constant changes to the Bail Act 1978 (NSW), changes which remove or restrict the presumption in favour of bail for a wide range of offences. The article will then examine some of the conceptual, cultural and practice shifts underlying the increase. These include: a shift away from a conception of bail as a procedural issue predominantly concerned with securing the attendance of the accused at trial and the integrity of the trial, to the use of bail for crime prevention purposes; the diminishing force of the presumption of innocence; the framing of a false opposition between an individual interest in liberty and a public interest in safety; a shift from determination of the individual case by reference to its own particular circumstances to determination by its classification within pre-set legislative categories of offence types and previous convictions; a double jeopardy effect arising in relation to people with previous convictions for which they have already been punished; and an unacknowledged preventive detention effect arising from the increased emphasis on risk. Many of these conceptual shifts are apparent in the explosion in bail conditions and the KPI-driven policing of bail conditions and consequent rise in revocations, especially in relation to juveniles. The paper will conclude with a note on the NSW Government’s response to the NSW LRC Report in the form of a Bail Bill (2013) and brief speculation as to its likely effects.

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