188 research outputs found
Structural correlations in diffusiophoretic colloidal mixtures with nonreciprocal interactions
Nonreciprocal effective interaction forces can occur between mesoscopic particles in colloidal suspensions that are driven out of equilibrium. These forces violate Newton's third law actio = reactio on coarse-grained length and time scales. Here we explore the statistical mechanics of Brownian particles with nonreciprocal effective interactions. Our model system is a binary fluid mixture of spherically symmetric, diffusiophoretic mesoscopic particles, and we focus on the time-averaged particle pair- and triplet-correlation functions. Based on the many-body Smoluchowski equation we develop a microscopic statistical theory for the particle correlations and test it by computer simulations. For model systems in two and three spatial dimensions, we show that nonreciprocity induces distinct nonequilibrium pair correlations. Our predictions can be tested in experiments with chemotactic colloidal suspensions
Wave energy localization by self-focusing in large molecular structures: a damped stochastic discrete nonlinear Schroedinger equation model
Wave self-focusing in molecular systems subject to thermal effects, such as
thin molecular films and long biomolecules, can be modeled by stochastic
versions of the Discrete Self-Trapping equation of Eilbeck, Lomdahl and Scott,
and this can be approximated by continuum limits in the form of stochastic
nonlinear Schroedinger equations.
Previous studies directed at the SNLS approximations have indicated that the
self-focusing of wave energy to highly localized states can be inhibited by
phase noise (modeling thermal effects) and can be restored by phase damping
(modeling heat radiation).
We show that the continuum limit is probably ill-posed in the presence of
spatially uncorrelated noise, at least with little or no damping, so that
discrete models need to be addressed directly. Also, as has been noted by other
authors, omission of damping produces highly unphysical results.
Numerical results are presented for the first time for the discrete models
including the highly nonlinear damping term, and new numerical methods are
introduced for this purpose. Previous conjectures are in general confirmed, and
the damping is shown to strongly stabilize the highly localized states of the
discrete models. It appears that the previously noted inhibition of nonlinear
wave phenomena by noise is an artifact of modeling that includes the effects of
heat, but not of heat loss.Comment: 22 pages, 13 figures, revision of talk at FPU+50 conference in Rouen,
June 200
Towards integrated superconducting detectors on lithium niobate waveguides
Superconducting detectors are now well-established tools for low-light
optics, and in particular quantum optics, boasting high-efficiency, fast
response and low noise. Similarly, lithium niobate is an important platform for
integrated optics given its high second-order nonlinearity, used for high-speed
electro-optic modulation and polarization conversion, as well as frequency
conversion and sources of quantum light. Combining these technologies addresses
the requirements for a single platform capable of generating, manipulating and
measuring quantum light in many degrees of freedom, in a compact and
potentially scalable manner. We will report on progress integrating tungsten
transition-edge sensors (TESs) and amorphous tungsten silicide superconducting
nanowire single-photon detectors (SNSPDs) on titanium in-diffused lithium
niobate waveguides. The travelling-wave design couples the evanescent field
from the waveguides into the superconducting absorber. We will report on
simulations and measurements of the absorption, which we can characterize at
room temperature prior to cooling down the devices. Independently, we show how
the detectors respond to flood illumination, normally incident on the devices,
demonstrating their functionality.Comment: 7 pages, 4 figure
Specifications for a new or remodeled mathematics classroom.
Thesis (Ed.M.)--Boston Universit
Melanocyte differentiation antigen RAB38/NY-MEL-1 induces frequent antibody responses exclusively in melanoma patients
Expression pattern and immunogenicity are critical issues that define tumor antigens as diagnostic markers and potential targets for immunotherapy. The development of SEREX (serological analysis of recombinant expression libraries) has provided substantial progress in the identification of tumor antigens eliciting both cellular and humoral immune responses in cancer patients. By SEREX, we have previously identified RAB38/NY-MEL-1 as a melanocyte differentiation antigen that is highly expressed in normal melanocytes and melanoma tissues but not in other normal tissues or cancer types. In this study, we further demonstrate that RAB38/NY-MEL-1 is strongly immunogenic, leading to spontaneous antibody responses in a significant proportion of melanoma patients. The immune response occurs solely in malignant melanoma patients and was not detected in patients with other diseases, such as vitiligo, affecting melanocytes. Fine analysis of the spontaneous anti-RAB38/NY-MEL-1 antibody response reveals a polyclonal B cell recognition targeting various epitopes, although a dominant immunogenic region was preferentially recognized. Interestingly, our data indicate that this recognition is not rigid in the course of a patient's response, as the dominant epitope changes during the disease evolution. Implications for the understanding of spontaneous humoral immune responses are discusse
Abelian Higgs Hair for Black Holes
We find evidence for the existence of solutions of the Einstein and Abelian
Higgs field equations describing a black hole pierced by a Nielsen-Olesen
vortex. This situation falls outside the scope of the usual no-hair arguments
due to the non-trivial topology of the vortex configuration and the special
properties of its energy-momentum tensor. By a combination of numerical and
perturbative techniques we conclude that the black hole horizon has no
difficulty in supporting the long range fields of the Nielsen Olesen string.
Moreover, the effect of the vortex can in principle be measured from infinity,
thus justifying its characterization as black hole ``hair".Comment: 31 pages, plain tex, 7 figures included. minor corrections and
references adde
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VOICE - Entwicklung der ersten evidenzbasierten Digitalen Gesundheitsanwendung für Minderjährige mit Angststörungen: Eine Blaupause für ein Beteiligungskonzept mit Minderjährigen
Angststörungen gehören zu den häufigsten psychischen Erkrankungen im Kindesalter. Sie persistieren oftmals bis ins Erwachsenenalter und können mit einer erhöhten Belastung durch weitere psychische Störungen, familiäre Konflikte, chronischen Stress sowie einer verringerten Lebenszufriedenheit einhergehen. Dies verdeutlicht den dringenden Bedarf an schneller und zugänglicher Unterstützung. Obwohl sich die Therapie von Angststörungen im Kindesalter in den letzten Jahren verbessert hat, besteht weiterhin großer Verbesserungsbedarf. Viele betroffene Familien erhalten die notwendige Hilfe nicht und in Deutschland sind die Wartezeiten auf Therapie besonders lang. Daher braucht es mehr klinische Forschung mit hoher Relevanz für die Patientenversorgung. Ein Weg zur Verbesserung von Therapieangeboten ist der Einbezug von Betroffenen und ihren Angehörigen. Wenn Menschen, die von der Forschung und Behandlung betroffen sind, aktiv mitwirken, werden Studien relevanter und hilfreicher. Um sicherzustellen, dass ihre Meinungen und Bedürfnisse von Beginn an berücksichtigt werden, sollten sie Forschungsvorhaben und Interventionen mitgestalten. Leider ist dies bislang selten der Fall – insbesondere für Kinder. Dieses Projekt verfolgte daher drei Hauptziele:
1. Gemeinsam mit Kindern, Eltern, TherapeutInnen und Forschenden wurde ein Leitfaden zur Partizipation junger Menschen in der psychischen Gesundheitsforschung entwickelt.
2. Es wurde eine qualitativ hochwertige Gesundheits-App zur Unterstützung von Kindern mit Angststörungen während der Wartezeit auf eine Therapie erarbeitet.
3. Partizipativ wurde eine klinische Studie zur Wirksamkeit dieser App geplant
A Quasi‐Multinary Composite Coating on a Nickel‐Rich NCM Cathode Material for All‐Solid‐State Batteries
Inorganic solid-state batteries are attracting significant interest as a contender to conventional liquid electrolyte-based lithium-ion batteries but still suffer from several limitations. The search for advanced coatings for protecting cathode materials in solid-state batteries to achieve interfacial stability is a continuing challenge. In the present work, the surface of an industrially relevant Ni-rich LiNiCoMnO cathode material, NCM-851005 (85 % Ni), was modified by applying a coating containing Li, Nb and Zn, aiming at a composition LiZnNbO, by means of sol-gel chemistry. Detailed characterization using scanning transmission electron microscopy combined with energy-dispersive X-ray spectroscopy and nano-beam electron diffraction showed that the surface layer after heating in O at 500 °C contains LiNbO nanocrystals and LiCO, with Zn presumably acting as a dopant. The protective coating on the NCM-851005 secondary particles significantly increased the cycling performance (reversible capacity, rate capability etc.) and stability of full cells using argyrodite LiPSCl as solid electrolyte. Interestingly, the level of improvement is superior to that achieved with conventional LiNbO coatings
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