1,371 research outputs found
Symmetric duality for a class of nondifferentiable multi-objective fractional variational problems
AbstractWe introduce a symmetric dual pair for a class of nondifferentiable multi-objective fractional variational problems. Weak, strong, converse and self duality relations are established under certain invexity assumptions. The paper includes extensions of previous symmetric duality results for multi-objective fractional variational problems obtained by Kim, Lee and Schaible [D.S. Kim, W.J. Lee, S. Schaible, Symmetric duality for invex multiobjective fractional variational problems, J. Math. Anal. Appl. 289 (2004) 505–521] and symmetric duality results for the static case obtained by Yang, Wang and Deng [X.M. Yang, S.Y. Wang, X.T. Deng, Symmetric duality for a class of multiobjective fractional programming problems, J. Math. Anal. Appl. 274 (2002) 279–295] to the dynamic case
Mesenchymal stem cell secretes microparticles enriched in pre-microRNAs
10.1093/nar/gkp857Nucleic Acids Research381215-22
Learning from past failures: Challenges with monoclonal antibody therapies for COVID-19
COVID-19, the disease caused by infection with SARS-CoV-2, requires urgent development of therapeutic interventions. Due to their safety, specificity, and potential for rapid advancement into the clinic, monoclonal antibodies (mAbs) represent a highly promising class of antiviral or anti-inflammatory agents. Herein, by analyzing prior efforts to advance antiviral mAbs for other acute respiratory infections (ARIs), we highlight the challenges faced by mAb-based immunotherapies for COVID-19. We present evidence supporting early intervention immediately following a positive diagnosis via inhaled delivery of mAbs with vibrating mesh nebulizers as a promising approach for the treatment of COVID-19
Lowest-energy structures of 13-atom binary clusters: Do icosahedral clusters exist in binary liquid alloys?
Although the existence of 13-atom icosahedral clusters in one-component
close-packed undercooled liquids was predicted more than half a century ago by
Frank, the existence of such icosahedral clusters is less clear in liquid
alloys. We study the lowest-energy structures of 13-atom AxB13-x Lennard-Jones
binary clusters using the modified space-fixed genetic algorithm and the
artificial Lennard-Jones potential designed by Kob and Andersen. Curiously, the
lowest-energy structures are non-icosahedral for almost all compositions. The
role played by the icosahedral cluster in a binary glass is questionable.Comment: 10 pages, 3 figure (conference paper of LAM12) to be published in J.
Non-Crystalline Solid
Elementary excitations in one-dimensional spin-orbital models: neutral and charged solitons and their bound states
We study, both numerically and variationally, the interplay between different
types of elementary excitations in the model of a spin chain with anisotropic
spin-orbit coupling, in the vicinity of the "dimer line" with an exactly known
dimerized ground state. Our variational treatment is found to be in a
qualitative agreement with the exact diagonalization results. Soliton pairs are
shown to be the lowest excitations only in a very narrow region of the phase
diagram near the dimer line, and the phase transitions are always governed by
magnon-type excitations which can be viewed as soliton-antisoliton bound
states. It is shown that when the anisotropy exceeds certain critical value, a
new phase boundary appears. In the doped model on the dimer line, the exact
elementary charge excitation is shown to be a hole bound to a soliton. Bound
states of those "charged solitons" are studied; exact solutions for N-hole
bound states are presented.Comment: 11 pages revtex, 6 figure
Bispecific binder redirected lentiviral vector enables in vivo engineering of CAR-T cells
Background Chimeric antigen receptor (CAR) T cells have shown considerable promise as a personalized cellular immunotherapy against B cell malignancies. However, the complex and lengthy manufacturing processes involved in generating CAR T cell products ex vivo result in substantial production time delays and high costs. Furthermore, ex vivo expansion of T cells promotes cell differentiation that reduces their in vivo replicative capacity and longevity. Methods Here, to overcome these limitations, CAR-T cells are engineered directly in vivo by administering a lentivirus expressing a mutant Sindbis envelope, coupled with a bispecific antibody binder that redirects the virus to CD3 + human T cells. Results This redirected lentiviral system offers exceptional specificity and efficiency; a single dose of the virus delivered to immunodeficient mice engrafted with human peripheral blood mononuclear cells generates CD19-specific CAR-T cells that markedly control the growth of an aggressive pre-established xenograft B cell tumor. Conclusions These findings underscore in vivo engineering of CAR-T cells as a promising approach for personalized cancer immunotherapy
Aging dynamics in a colloidal glass of Laponite
The aging dynamics of colloidal suspensions of Laponite, a synthetic clay, is
investigated using dynamic light stattering (DLS) and viscometry after a quench
into the glassy phase. DLS allows to follow the diffusion of Laponite particles
and reveals that there are two modes of relaxation. The fast mode corresponds
to a rapid diffusion of particles within "cages" formed by the neighboring
particles. The slow mode corresponds to escape from the cages: its average
relaxation time increases exponentially fast with the age of the glass. In
addition, the slow mode has a broad distribution of relaxation times, its
distribution becoming larger as the system ages. Measuring the concomitant
increase of viscosity as the system ages, we can relate the slowing down of the
particle dynamics to the viscosity.Comment: 9 pages, 8 Postscript figures, submitted to Phys. Rev.
X-ray standing wave and reflectometric characterization of multilayer structures
Microstructural characterization of synthetic periodic multilayers by x-ray
standing waves have been presented. It has been shown that the analysis of
multilayers by combined x-ray reflectometry (XRR) and x-ray standing wave (XSW)
techniques can overcome the deficiencies of the individual techniques in
microstructural analysis. While interface roughnesses are more accurately
determined by the XRR technique, layer composition is more accurately
determined by the XSW technique where an element is directly identified by its
characteristic emission. These aspects have been explained with an example of a
20 period Pt/C multilayer. The composition of the C-layers due to Pt
dissolution in the C-layers, PtC, has been determined by the XSW
technique. In the XSW analysis when the whole amount of Pt present in the
C-layers is assumed to be within the broadened interface, it l eads to larger
interface roughness values, inconsistent with those determined by the XRR
technique. Constraining the interface roughness values to those determined by
the XRR technique, requires an additional amount of dissolved Pt in the
C-layers to expl ain the Pt fluorescence yield excited by the standing wave
field. This analysis provides the average composition PtC of the
C-layers .Comment: 12 pages RevTex, 10 eps figures embedde
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