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An Investigation of the Effects of Quantum Dot Nanoparticles on Photopolymer Resin for Use in PolyJet Direct 3D Printing
The addition of quantum dot (QD) nanoparticles to additive manufacturing (AM) media
provides the opportunity to create artifacts with complex geometry that also have unique optical
characteristics. However, the addition of nanoparticles can significantly alter the rheology of a
material and make it difficult to process in an AM context. In this study, quantum dots were
added to a photopolymer resin in varying mass ratios to photopolymer, and their effects on the
viscosity, surface tension, and jetting ability of the suspension were investigated. Results show
that printability was not significantly affected by the presence of quantum dots in mass
concentrations less than or equal to 0.5%. The nanosuspensions were deposited via inkjet to
demonstrate the feasibility of creating optically-unique artifacts.Mechanical Engineerin
Orbifold instantons, moment maps, and Yang-Mills theory with sources
We revisit the problem of constructing instantons on ADE orbifolds R4/Γ and point out some subtle relations with the complex structure on the orbifold. We consider generalized instanton equations on R4/Γ which are BPS equations for the Yang-Mills equations with an external current. The relation between level sets of the moment maps in the hyper-Kähler quotient construction of the instanton moduli space and sources in the Yang-Mills equations is discussed. We describe two types of spherically symmetric Γ-equivariant connections on complex V bundles over R4/Γ which are tailored to the way in which the orbifold group acts on the fibers. Some explicit Abelian and non-Abelian SU(2)-invariant solutions to the instanton equations on the orbifold are worked out. © 2013 American Physical Society
Instantons and Yang-Mills Flows on Coset Spaces
We consider the Yang-Mills flow equations on a reductive coset space G/H and
the Yang-Mills equations on the manifold R x G/H. On nonsymmetric coset spaces
G/H one can introduce geometric fluxes identified with the torsion of the spin
connection. The condition of G-equivariance imposed on the gauge fields reduces
the Yang-Mills equations to phi^4-kink equations on R. Depending on the
boundary conditions and torsion, we obtain solutions to the Yang-Mills
equations describing instantons, chains of instanton-anti-instanton pairs or
modifications of gauge bundles. For Lorentzian signature on R x G/H, dyon-type
configurations are constructed as well. We also present explicit solutions to
the Yang-Mills flow equations and compare them with the Yang-Mills solutions on
R x G/H.Comment: 1+12 page
Non-Abelian Vortices, Super-Yang-Mills Theory and Spin(7)-Instantons
We consider a complex vector bundle E endowed with a connection A over the
eight-dimensional manifold R^2 x G/H, where G/H = SU(3)/U(1)xU(1) is a
homogeneous space provided with a never integrable almost complex structure and
a family of SU(3)-structures. We establish an equivalence between G-invariant
solutions A of the Spin(7)-instanton equations on R^2 x G/H and general
solutions of non-Abelian coupled vortex equations on R^2. These vortices are
BPS solitons in a d=4 gauge theory obtained from N=1 supersymmetric Yang-Mills
theory in ten dimensions compactified on the coset space G/H with an
SU(3)-structure. The novelty of the obtained vortex equations lies in the fact
that Higgs fields, defining morphisms of vector bundles over R^2, are not
holomorphic in the generic case. Finally, we introduce BPS vortex equations in
N=4 super Yang-Mills theory and show that they have the same feature.Comment: 14 pages; v2: typos fixed, published versio
Hidden Symmetries and Integrable Hierarchy of the N=4 Supersymmetric Yang-Mills Equations
We describe an infinite-dimensional algebra of hidden symmetries of N=4
supersymmetric Yang-Mills (SYM) theory. Our derivation is based on a
generalization of the supertwistor correspondence. Using the latter, we
construct an infinite sequence of flows on the solution space of the N=4 SYM
equations. The dependence of the SYM fields on the parameters along the flows
can be recovered by solving the equations of the hierarchy. We embed the N=4
SYM equations in the infinite system of the hierarchy equations and show that
this SYM hierarchy is associated with an infinite set of graded symmetries
recursively generated from supertranslations. Presumably, the existence of such
nonlocal symmetries underlies the observed integrable structures in quantum N=4
SYM theory.Comment: 24 page
Некоторые моменты сопоставительного анализа фонетики русского и туркменского языков
The comparison of some phonetic aspects of Russian and Turkmen languages has been given in this article.В статье дается сопоставление некоторых аспектов фонетического строя русского и туркменского языков
К вопросу о роли гласных и согласных в звуковых традициях русского и туркменского языков
The analysis of vowel’s and consonant’s part at Russian and Turkmen languages has been given in this article.В статье дается анализ роли гласных и согласных звуков в русском и туркменском языках
К вопросу о соответствии видов русских приставочных глаголов туркменским эквивалентам
Russian prefix verbs and their equivalents in the Turkmen language are examined in the article. The analysis of some aspects of the subject matter understudy is givenВ статье дается сопоставительный анализ глаголов совершенного и несовершенного видов русского и туркменского языков
Про створення навчального посібника з граматики для студентів-медиків 1 курсу
Basic components of the grammar schoolbook’s models have been considered in this article. Methodic basis of this aspect training organization has been given. System of exercises and tasks in forming linguistic competence of the 1-st year medical students has been also described.У статті розглядаються основні складові моделі навчального посібника з граматики, дається методичне обґрунтування організації навчання даному аспекту, описується система завдань та вправ з формування мовної компетенції студентів-медиків першого курсу
Anticancer substances of mushroom origin
The present status of investigations about the anticancer activity which is inherent to medicinal mushrooms, as well as their biomedical potential and future prospects are discussed. Mushroom products and extracts possess promising immunomodulating and anticancer effects, so the main biologically active substances of mushrooms responsible for immunomodulation and direct cytotoxicity toward cancer cell lines (including rarely mentioned groups of anticancer mushroom proteins), and the mechanisms of their antitumor action were analyzed. The existing to date clinical trials of mushroom substances are mentioned. Mushroom anticancer extracts, obtained by the different solvents, are outlined. Modern approaches of cancer treatment with implication of mushroom products, including DNA vaccinotherapy with mushroom immunomodulatory adjuvants, creation of prodrugs with mushroom lectins that can recognize glycoconjugates on the cancer cell surface, development of nanovectors etc. are discussed. The future prospects of mushroom anticancer substances application, including chemical modification of polysaccharides and terpenoids, gene engineering of proteins, and implementation of vaccines are reviewed. Key Words: mushrooms, anticancer substances, extracts, vaccinotherapy
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