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Janus\u27s Two Faces
No full textIn ancient Roman religion and myth, Janus is the god of beginnings, transitions, and endings. He is often depicted as having two faces, one looking to the future and one to the past. The Supreme Court’s Janus v AFSCME case of last Term is fittingly named. Stunning in its disregard of principles of stare decisis, Janus overruled the forty-year-old precedent Abood v Detroit Board of Education. The Janus decision marks the end of the post–New Deal compromise with respect to public sector unions and the First Amendment. Looking to the future, Janus lays the groundwork for further attack on labor rights—as well as for a broader erosion of civil society and democracy at the expense of corporate power. In that way, Janus represents an unequivocal transition to what Justice Kagan termed a “weaponized” view of the First Amendment among the Court’s majority—indeed, far more so than her dissent elaborates. But Janus may also have another, more hopeful, forward-looking face. Ultimately, Janus’s undoing of the compromise that governed union fees for nearly fifty years provides the opportunity for a systematic rethinking of the relationship between labor and the Constitution and, more generally, of the meaning of the First Amendment. In Janus, the dissenters on the Court gestured at this broader project, but their future-facing efforts were partial and unsatisfying. Instead, they looked backward to Abood, a precedent the result of which was tolerable, but the reasoning of which was deeply flawed. Abood adopted a categorical approach to compelled subsidization of speech. It also fundamentally misconstrued the role of unions and their relationship to politics, the public’s interest in labor relations, and the nature of the “public square.” In so doing, Abood helped lay the groundwork for Janus’s demolition of union rights and for its protection of a right to exit from democratic institutions. Though stare decisis counseled in favor of maintaining Abood, its demise now opens up space to begin to flesh out what, in this setting, Justice Kagan’s promise of a “First Amendment meant for better things” might look like. This essay takes a first step toward that end
Simulation of diffusiophoresis force and the confinement effect of Janus particles with the continuum method
No full textThe Janus particle is a special class of colloidal particle that has different surface characteristics on its two hemispheres. In the microsystem field, an interesting application is the Janus particle's self-propulsion. Diffusiophoresis (DFP) provides one possible mechanism to explain this phenomenon. In this paper, we used the continuum model to simulate DFP and to study the confinement effect of Janus particles travelling on the substrate. In the experiment, we noticed a special quasi-1D motion, in which the DFP force is dominant and particles move at a constant velocity within a short interval approximately along a straight line. This enables us to adopt a reference frame to numerically study the distributions of the flow field and concentration field and hence to evaluate the different forces. Because the confinement effect has a great influence on the magnitude of forces, the gaps were calculated accurately according to the force balance principle. Meanwhile, the fitting coefficients to match the experimental and numerical results were suggested. This result may help us to get a better understanding of self-propulsion and is also beneficial for designing a DFP-based micro-device. (C) 2014 Author(s)
Janus\u27s Two Faces
No full textIn ancient Roman religion and myth, Janus is the god of beginnings, transitions, and endings. He is often depicted as having two faces, one looking to the future and one to the past. The Supreme Court’s Janus v AFSCME case of last Term is fittingly named.1 Stunning in its disregard of principles of stare decisis, Janus overruled the forty-yearold precedent Abood v Detroit Board of Education. 2 The Janus decision marks the end of the post–New Deal compromise with respect to public sector unions and the FirstAmendment.Looking to the future, Janus lays the groundwork for further attack on labor rights—as well as for a broader erosion of civil society and democracy at the expense of corporate power. In thatway, Janusrepresents an unequivocal transition to what Justice Kagan termed a “weaponized” view of the First Amendment among the Court’s majority—indeed, far more so than her dissent elaborates
Janus particle microshuttle: 1D directional self-propulsion modulated by AC electrical field
No full textA catalytic Janus particle is capable of gaining energy from the surrounding fuel solution to drive itself to move continuously, which has an important impact in different fields, especially the field of micro-systems. However, the randomness of self-propulsion at the microscale restricts its use in practice. Achieving a directed self-propelled movement would greatly promote the application of the Janus particle. We proved experimentally that an AC electric field was an effective way to suppress Brownian motion and control the direction of self-propelled movement. The self-propulsion and dielectrophoretic response of a 2μm Janus particle were observed and the related basic data were collected. Interdigital electrodes, 20 μm in width, were energized in pulsed style to modulate the self-propulsion, which resulted in a shuttle-style motion in which a single Janus particle moved to and fro inside the strip electrode. The change of direction depends on its unique position: the catalyst side is always pointed outward and the orientation angle relative to the electrode is about 60°. Numerical simulation also proved that this position is reasonable. The present study could be beneficial with regard to self-propulsion and AC electrokinetics of the Janus particle
Hollow Janus cylinders at liquid interfaces
No full textIn this dissertation, capillary-induced interactions and self-assembly behavior of amphiphilic hollow Janus cylinders at an air-water interface is numerically investigated. First, preferred orientation of a single hollow Janus cylinder is determined as a function of amphiphilicity and aspect ratio. When the cylinder is horizontal (long axis parallel to the interface), the shape of the deformed interface and the resulting capillary-induced interactions between a pair of cylinders is examined. In addition, preferred tip-to-tip or side-by-side assembly behavior of a pair of cylinders is determined by minimizing the total interfacial energy of the system. The preferred assembly behavior of a pair of hollow Janus cylinders is side-by-side for higher amphiphilicities, but as the amphiphilicity is reduced, tip-to-tip orientation becomes similarly preferable. The case of hollow Janus cylinders is also compared with their homogeneous counterparts as well as with solid homogeneous and solid Janus cylinders. The significant difference between Janus and homogeneous hollow cylinders is that the preferred orientation of a homogeneous hollow cylinder is horizontal with respect to the interface for given contact angles and at large aspect ratios. Meanwhile hollow Janus cylinders with large aspect ratios and amphiphilicities (beta≥ 20) prefer a vertical orientation (piercing the interface). The preferred orientation of a single solid Janus cylinder behaves similarly to its hollow counterpart except it prefers a vertical orientation at higher amphiphilicities. In comparison, single hollow and solid homogeneous cylinders have almost similar preferred orientation. The outcome of this study may provide insight on self-assembly behavior of model hollow particles, such as carbon nanotubes, at liquid interfaces for fabrication of functional monolayers or for use as interface stabilizers in foam and emulsions.M.S.Includes bibliographical referencesby Robert Wei
Note on generalized Janus configurations
No full textWe study several aspects of generalized Janus configuration, which includes a theta term. We investigate the vacuum structure of the theory and find that unlike the Janus configuration without theta term there is no nontrivial vacuum. We also discuss BPS soliton configuration both by supersymmetry analysis and from energy functional. The half BPS configurations could be realized by introducing transverse (p,q)-strings in original brane configuration corresponding to generalized Janus configuration. It turns out the BPS soliton could be taken as modified dyon. We discuss the solution of half BPS equations for the sharp interface case. Moreover we construct less supersymmetric Janus configuration with theta term.Physics, Particles & FieldsSCI(E)2ARTICLE2nul
Orientation of Spherical Janus Nanoparticles: Force and Torque Calculations due to an External Electric Field
No full textJanus particles are colloidal particles for which one half of the surface has different attributes than the other half. One property of a spherical dielectric particle with half of its surface covered by a layer of another dielectric or metal is that it has a non-uniform scattering pattern when exposed to light. However, the angle with which the light is shone on the particle has a large effect on the scattering pattern produced. Thus it is important that we are able to orient these Janus particles. The orientation can be controlled if we apply an electric field to the particle for example. The movement of colloidal particles with an electric field is widely studied and this field is called dielectrophoresis. For a Janus particle, the calculations for the force and torque become complicated. The movement and rotation of these particles have been studied, however, no analytic solution has been found. In this report, we derive a semi-analytic description of the force and torque due to an external electric field on a spherical Janus particle. For this, first the potential due to an external electric field is determined and then the force and torque are calculated with two methods: the dipole approximation and the Maxwell Stress Tensor method. In the dipole approximation, there is no force on the Janus particle. But, there is a torque on the particle in the dipole approximation. Due to this torque, the Janus particle will orient itself such that its cap points in the direction perpendicular to the applied field. For the torque calculated with the Maxwell Stress Tensor, we get a similar result as in the dipole approximation. On the other hand, according to the calculations with the stress tensor, there is a relatively small force on the particle.Applied Mathematics | Applied Physic
Emulsion-based synthesis and characterization of biphasic Janus particles for dual drug delivery
No full textJanus particles exhibit many unique chemical, optical, electrical, and physical properties due to their two chemically distinct surfaces. They are highly sought after for diverse applications across many fields including electronics, energy, catalysis, and emulsion stabilization. Janus particles also hold great promise in the field of biomedical engineering as drug delivery vehicles, theranostic platforms, and components of biosensors. As drug delivery vehicles, they offer a platform for co-encapsulating drugs with widely disparate solubility as well as independent release kinetics. However, large-scale synthesis methods are needed before Janus particles can realize their full potential in biomedicine. A novel technique based on the phase separation of two immiscible polymers and/or lipids within single O/W and double W/O/W emulsion droplets is presented for the production of Janus particles. The effects of various formulation and process variables on final Janus particle properties including particle size, stability, morphology, and encapsulation efficiency are studied. A wide range of Janus particle morphologies were synthesized, including acorn-like, spherical, crescent moon, and two nearly separated droplets. From a purely thermodynamic perspective, particle shape is a function of the interfacial tensions between the two polymers, as well as the interfacial tensions between each of the polymers and the aqueous phase containing surfactant. These interfacial tensions are adjusted by changing the type and concentration of surfactant in the water phase, making a wide range of morphologies accessible. In order to quantifiably describe the influence of interfacial tension on particle morphology, a thermodynamic model for the prediction of Janus particle morphology was developed. The model is derived from first-principles, in which the exact shape of a Janus particle is extracted via total free energy minimization of Janus particles modeled as two overlapping semicircles. In reverse, particle geometry measurements obtained from microscopy can be applied to the model in order to explicitly calculate the volume ratio and the surface tension of each of the three interfaces. The ability to control Janus particle shape is of fundamental importance for many potential applications, as function depends on structure. Janus particles were applied to a case study involving the treatment of lung cancer with doxorubicin, a broad spectrum chemotherapeutic, and curcumin, a bioflavanoid with antioxidant, anti-inflammatory, and antitumor effects. The Janus particles containing doxorubicin and curcumin completely inhibited tumor growth over a four-week treatment period, attesting to the advantages of bicompartmental Janus carriers for dual drug delivery of synergistic compounds.Ph.D.Includes bibliographical referencesby Jennifer Sherri Winkle
Janus Parallelism in Job 1:20
No full textIn Job 1:20, Job performs four actions: 1) he rends his garment; 2) he shears his head; 3) he falls to the ground; and 4) he prostrates himself. The third of these can be read either (with the first two) as an act of mourning or (with the last) as an act of worship. I suggest that this is a deliberate literary choice: the poetic technique of Janus parallelism. Since Janus parallelism has already been demonstrated to be both frequent in the book of Job and significant for its meaning, this unexpected Janus parallelism in the prose portion of the book confirms that those chapters are not an early survival but a creation of the author of the book as a whole
Janus Bifrons, Janus Cerus: strategie traduttive e autotraduttive in Nabokov
No full textJanus Bifrons, Janus Cerus: Nabokov’s translation and Self-translation
Strategies
The first part of the paper delves into the question of the writer’s approaches to literary
translation. A distinction between his translations into Russian (this is the case of Alice in
Wonderland,1923, Anja v Strane Čudes) and those into English (Evgenij Onegin, 1964,Eu-gene Onegin) is in order. It should be underlined, however, that in this reference frame the
translation is conducted on works belonging to otherauthors. Nonetheless, these examples
make it possible to discuss Nabokov’s distinct, if not contradictory, theoretical position con-cerning the practice of translation. In fact, his opinion dramatically changes depending on
the direction of translation, from Russian into English or the other way round.
The second focus is on the problem of translating one’s own text. In Nabokov’s literary
career this activity was undertaken from the 1930s onwards. It is possible here to mention a
novel such as Otčajanie(Despair, 1936), which the author self-translated twice into English
(1937, 1965). Finally, the paper considers Nabokov’s collaboration with his son Dmitri, because of its theoretical importance. Examples of this cooperation can be found, for instance,
in the translation of Priglašenie na kazn’ (1938, Invitation to a Beheading, 1959), and Cose
Trasparenti(1975, Transparent Things, 1972). The legitimacy of the translation and its value
are called into question, while the role of the author in this context is also discussed
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