3,506 research outputs found
Targeting kidney mesangium by nanoparticles of defined size
Nanoparticles are being investigated for numerous medical applications and are showing potential as an emerging class of carriers for drug delivery. Investigations on how the physicochemical properties (e.g., size, surface charge, shape, and density of targeting ligands) of nanoparticles enable their ability to overcome biological barriers and reach designated cellular destinations in sufficient amounts to elicit biological efficacy are of interest. Despite proven success in nanoparticle accumulation at cellular locations and occurrence of downstream therapeutic effects (e.g., target gene inhibition) in a selected few organs such as tumor and liver, reports on effective delivery of engineered nanoparticles to other organs still remain scarce. Here, we show that nanoparticles of ~75 ± 25-nm diameters target the mesangium of the kidney. These data show the effects of particle diameter on targeting the mesangium of the kidney. Because many diseases originate from this area of the kidney, our findings establish design criteria for constructing nanoparticle-based therapeutics for targeting diseases that involve the mesangium of the kidney
Resonance production by neutrinos: I. J=3/2 Resonances
The article contains general formulas for the production of J=3/2 resonances
by neutrinos and antineutrinos. It specializes to the P_{33}(1232) resonance
whose form factors are determined by theory and experiment and then are
compared with experimental results at low and high energies. It is shown that
the minimum in the low Q^2 region is a consequence of a combined effect from
the vanishing of the vector form factors, the muon mass and Pauli blocking.
Several improvements for the future investigations are suggested.Comment: 10 pages, LaTeX, misprints corrected, 1 reference adde
Spin states of zigzag-edged Mobius graphene nanoribbons from first principles
Mobius graphene nanoribbons have only one edge topologically. How the
magnetic structures, previously associated with the two edges of zigzag-edged
flat nanoribbons or cyclic nanorings, would change for their Mobius
counterparts is an intriguing question. Using spin-polarized density functional
theory, we shed light on this question. We examine spin states of zigzag-edged
Mobius graphene nanoribbons (ZMGNRs) with different widths and lengths. We find
a triplet ground state for a Mobius cyclacene, while the corresponding
two-edged cyclacene has an open-shell singlet ground state. For wider ZMGNRs,
the total magnetization of the ground state is found to increase with the
ribbon length. For example, a quintet ground state is found for a ZMGNR. Local
magnetic moments on the edge carbon atoms form domains of majority and minor
spins along the edge. Spins at the domain boundaries are found to be
frustrated. Our findings show that the Mobius topology (i.e., only one edge)
causes ZMGNRs to favor one spin over the other, leading to a ground state with
non-zero total magnetization.Comment: 17 pages, 4 figure
Magnetic and chemical properties of Cr-based films grown on GaAs(001)
We have investigated the magnetic and chemical properties of very thin Cr
films, CrAs, and arsenized Cr grown by molecular beam epitaxy on Ga As (001),
using x-ray photoemission spectroscopy and SQUID magnetometry. Distintic
preparation procedures have been used with the purpose to undestand the origin
of the ferromagneti signal observed for this system. It results that Ga
segregation and chemical reactivity between Ga and Cr have negligible
contribution in the formation of different thi films. A clear ferromagnetic
response even at room temperature suggests the existence of a very thin
interfacial layer formed that can eventually be burid during the growth
process.Comment: 16 pages, 6 figure
Decoupling of optoelectronic properties from morphological changes in sodium treated kesterite thin film solar cells
Sodium is typically used during the synthesis of kesterite thin films to enhance the performance of solar cells. As sodium tends to affect grain growth and morphology, it is difficult to analyse solely the electronic effects of sodium as dopant. To decouple the structural and electronic effects from each other, two processes were designed in this work to successfully incorporate sodium into a vacuum-processed Cu2ZnSnSe4absorber without changing the morphology. A thin layer of NaF is deposited before precursor deposition (Pre-NaF) or after absorber synthesis to undergo a post deposition treatment (NaF-PDT). While composition and distribution of matrix elements remain unchanged, the sodium concentration is increased upon sodium treatment up to 140 ppm as measured by inductively coupled plasma mass spectrometry. X-ray photoelectron spectroscopy showed that the surface composition was not altered. Within its detection limit, sodium was not present at the absorber surface. For a Pre-NaF sample measured with atom probe tomography a sodium concentration of 30 ppm was measured in a grain, suggesting that sodium might segregate at grain boundaries. The additional sodium content in the film leads to an increased acceptor concentration, which results in improved open-circuit voltage and fill factor.Financial support from the Swiss National Science Foundation (SNF)
in the network of the Indo-Swiss Joint Research Programme (ISJRP)
[IZLIZ2_157140/1] is gratefully acknowledged. T. Schwarz is grateful for the support of the
German Research Foundation (DFG) [Contract GA 2450/1-1]. R.
Caballero acknowledges financial support from Spanish MINECO
within the Ramón y Cajal program [RYC-2011-08521], MINECO project
WINCOST [ENE2016-80788-C5-2-R] and from Spanish Ministry of
Education, Culture and Sport within the José Castillejo program [CAS
15/00070
Comment on "On the subtleties of searching for dark matter with liquid xenon detectors"
In a recent manuscript (arXiv:1208.5046) Peter Sorensen claims that
XENON100's upper limits on spin-independent WIMP-nucleon cross sections for
WIMP masses below 10 GeV "may be understated by one order of magnitude or
more". Having performed a similar, though more detailed analysis prior to the
submission of our new result (arXiv:1207.5988), we do not confirm these
findings. We point out the rationale for not considering the described effect
in our final analysis and list several potential problems with his study.Comment: 3 pages, no figure
Charged current weak electroproduction of Delta resonance
We study the weak production of (i.e. and ) in the intermediate
energy range corresponding to the Mainz and TJNAF electron accelerators. The
differential cross sections are found to be of the order of cm/sr, over a range of angles which increases with energy. The
possibility of observing these reactions with the high luminosities available
at these accelerators, and studying the weak N- transition form factors
through these reactions is discussed. The production cross section of
N in the kinematic region of production is also estimated
and found to be small.Comment: 19 pages, REVTEX, 4 figure
How Family, Business, and Community Logics Shape Family Firm Behavior and “Rules of the Game” in an Organizational Field
Changes in risk factors for cardiovascular disease by baseline weight status in young adults who maintain or gain weight over 15 years: the CARDIA study
To examine whether changes in cardiovascular disease (CVD) risk factors differ by baseline weight status among young adults who maintained or gained weight
Nucleon to Delta Weak Excitation Amplitudes in the Non-relativistic Quark Model
We investigate the nucleon to Delta(1232) vector and axial vector amplitudes
in the non-relativistic quark model of the Isgur-Karl variety. A particular
interest is to investigate the SU(6) symmetry breaking, due to color hyperfine
interaction. We compare the theoretical estimates to recent experimental
investigation of the Adler amplitudes by neutrino scattering.Comment: \documentstyle[aps]{revtex}, 21pages; 11 postscript figures. Accepted
for publication by Phys. Rev.
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