22 research outputs found
Strategy for Fabricating Multiple-Shape-Memory Polymeric Materials via the Multilayer Assembly of Co-Continuous Blends
Shape-memory
polymeric materials containing alternating layers of thermoplastic
polyurethane (TPU) and co-continuous polyÂ(butylene succinate) (PBS)/polycaprolactone
(PCL) blends (denoted SLBs) were fabricated through layer-multiplying
coextrusion. Because there were two well-separated phase transitions
caused by the melt of PCL and PBS, both the dual- and triple-shape-memory
effects were discussed. Compared with the blending specimen with the
same components, the TPU/SLB multilayer system with a multicontinuous
structure and a plenty of layer interfaces was demonstrated to have
higher shape fixity and recovery ability. When the number of layers
reached 128, both the shape fixity and recovery ratios were beyond
95 and 85% in dual- and triple-shape-memory processes, respectively,
which were difficult to be achieved through conventional melt-processing
methods. On the basis of the classic viscoelastic theory, the parallel-assembled
TPU and SLB layers capable of maintaining the same strain along the
deforming direction were regarded to possess the maximum ability to
fix temporary shapes and trigger them to recover back to original
ones through the interfacial shearing effect. Accordingly, the present
approach provided an efficient strategy for fabricating outstanding
multiple-shape-memory polymers, which may exhibit a promising application
in the fields of biomedical devices, sensors and actuators, and so
forth
Influence of Cationic Precursors on CdS Quantum-Dot-Sensitized Solar Cell Prepared by Successive Ionic Layer Adsorption and Reaction
Successive
ionic layer adsorption and reaction (SILAR) is the most
extensively used method for the direct and simultaneous synthesis
and deposition of quantum dots (QDs) onto porous oxide films for quantum-dot-sensitized
solar cell (QDSC) applications. In this work, the noticeable influences
of the cationic precursors on the deposition of CdS QDs and the QDSC
performance have been studied. A careful comparison of two cationic
precursors, cadmium nitrate and cadmium acetate, for the preparation
of CdS QDSCs by the SILAR method showed that, compared to the commonly
used cadmium nitrate, cadmium acetate provided a significantly higher
deposition rate of CdS QDs on TiO<sub>2</sub> films. A solar cell
power conversion efficiency of 2.15% was achieved for a CdS QDSC employing
cadmium acetate as the cationic precursor, much higher than the value
of 1.44% obtained for the cell prepared using cadmium nitrate for
the same number of SILAR cycles. Control experiments in which the
recipes of the cationic precursor solutions were changed revealed
a dramatic effect of the cationic precursor pH on the deposition rate
of CdS QDs on the TiO<sub>2</sub> film. In addition, an appreciable
anomalous red shift, which became more pronounced with increasing
amount of QDs, was observed in both the optical absorption and photocurrent
spectra of CdS-sensitized TiO<sub>2</sub> films
Additional file 3: Figure S3. of Thrombin-induced, TNFR-dependent miR-181c downregulation promotes MLL1 and NF-κB target gene expression in human microglia
Schematic overview of thrombin’s effects upon miR-181c and MLL1 in human microglia. Thrombin (via PAR4) induces TNF-α secretion from human microglia [21]. Thrombin-induced TNF-α (via TNFR) suppresses miR-181c levels. This suppression of the inhibitory miR-181c promotes MLL1 expression, increases NF-κB activity, and upregulates downstream NF-κB target gene expression in human microglia. (JPG 456 kb
Additional file 2: Figure S2. of Thrombin-induced, TNFR-dependent miR-181c downregulation promotes MLL1 and NF-κB target gene expression in human microglia
Thrombin’s proteolytic activity contributed to its effects upon miR-181c and MLL1 expression in human microglia. (A) Validation of the thrombin-specific proteolytic inhibitor PPACK’s inhibition of thrombin activity. Thrombin’s proteolytic activity was measured via a chromogenic assay following pre-incubation in the absence or presence of various concentrations of PPACK. Heat-inactivated (boiled) thrombin was applied as a negative control. *p < 0.05 versus control, †p < 0.05 versus boiled thrombin, ‡p < 0.05 versus thrombin. (B) Pre-incubating with PPACK significantly inhibited thrombin’s effects upon miR-181c and MLL1 expression. *p < 0.05 versus control, †p < 0.05 versus thrombin. (TIF 598 kb
A Theoretical Study on the Structural and Energy Spectral Properties of Ce<sup>3+</sup> Ions Doped in Various Fluoride Compounds
Geometry optimization and wave function-based complete-active-space
self-consistent field-embedded cluster calculations have been performed
for a series of Ce<sup>3+</sup>-doped fluoride compounds (CaF<sub>2</sub>, YF<sub>3</sub>, LaF<sub>3</sub>, KMgF<sub>3</sub>, LiYF<sub>4</sub>, K<sub>2</sub>YF<sub>5</sub>, and KY<sub>3</sub>F<sub>10</sub>) to investigate local coordination structures, crystal field parameters,
and 5d<sup>1</sup> energy-level structures of doping Ce<sup>3+</sup> ions. The crystal-field parameters of Ce<sup>3+</sup> are extracted
from the calculated energies and wave functions. The calculated crystal-field
parameters and 5d<sup>1</sup> energy-level structures show excellent
consistency with the experimental results. Our calculations show that
the onset of 4f → 5d absorption, which is important in phosphors
and scintillators, can be well-predicted. Apart from that, the distortion
of local structure due to doping, the wave functions, and the crystal-field
parameters of 4f<sup>1</sup> and 5d<sup>1</sup> states of Ce<sup>3+</sup> in the hosts can be obtained. Those can seldom be obtained by fitting
empirical crystal-field Hamiltonian to experimental data but are required
by some detailed theoretical analysis, such as the calculation of
transition intensities and hyperfine splittings. The obtained crystal-field
parameters of Ce<sup>3+</sup> may also be useful for other lanthanide
ions in the same hosts
First-Principles Study on Structural, Electronic, and Spectroscopic Properties of γ‑Ca<sub>2</sub>SiO<sub>4</sub>:Ce<sup>3+</sup> Phosphors
In
the present work, geometric structures, electronic properties,
and 4f → 5d transitions of γ-Ca<sub>2</sub>SiO<sub>4</sub>:Ce<sup>3+</sup> phosphors have been investigated by using first-principles
calculations. Four categories of typical substitutions (i.e., the
doping of the Ce<sup>3+</sup> without the neighboring dopants/defects
and with the neighboring V<sub>O</sub><sup>••</sup>,
Al<sub>Si</sub>′, and V<sub>Ca</sub>″) are taken into
account to simulate local environments of the Ce<sup>3+</sup> located
at two crystallographically different calcium sites in the γ-Ca<sub>2</sub>SiO<sub>4</sub>. Density functional theory (DFT) geometry
optimization calculations are first performed on the constructed supercells
to obtain the information about the local structures and preferred
sites for the Ce<sup>3+</sup>. On the basis of the optimized crystal
structures, the electronic properties of γ-Ca<sub>2</sub>SiO<sub>4</sub>:Ce<sup>3+</sup> phosphors are calculated with the Heyd–Scuseria–Ernzerhof
screened hybrid functional, and the energies and relative oscillator
strengths of the 4f → 5d transitions of the Ce<sup>3+</sup> are derived from the <i>ab initio</i> embedded cluster
calculations at the CASSCF/CASPT2/RASSI-SO level. A satisfactory agreement
with the available experimental results is thus achieved. Moreover,
the relationships between the dopants/defects and the electronic as
well as spectroscopic properties of γ-Ca<sub>2</sub>SiO<sub>4</sub>:Ce<sup>3+</sup> phosphors have been explored. Such information
is vital, not least for the design of Ce<sup>3+</sup>-based phosphors
for the white light-emitting diodes (<i>w</i>-LEDs) with
excellent performance
DataSheet1_Therapeutic effects and underlying mechanism of poly (L-glutamic acid)-g-methoxy poly (ethylene glycol)/combretastatin A4/BLZ945 nanoparticles on Renca renal carcinoma.doc
Introduction: The prognosis of advanced renal carcinoma is not ideal, necessitating the exploration of novel treatment strategies. Poly(L-glutamic acid)-g-methoxy poly(ethylene glycol)/Combretastatin A4 (CA4)/BLZ945 nanoparticles (CB-NPs) possess the dual capability of CA4 (targeting blood vessels to induce tumor necrosis) and BLZ945 (inducing M2 macrophage apoptosis), thereby inhibiting tumor growth.Methods: Here, the therapeutic effects and underlying mechanism was explored by CCK-8 cytotoxicity experiment, transwell cell invasion and migration experiment, H&E, western blot analysis, immunohistochemistry, flow cytometry, and other techniques.Results: These results demonstrated that CB-NPs could inhibit the growth of Renca cells and subcutaneous tumors in mice, with an impressive tumor inhibition rate of 88.0%. Results suggested that CB-NPs can induce necrosis in renal carcinoma cells and tissues, downregulate VEGFA expression, promote renal carcinoma cell apoptosis, and reduce the polarization of M2 macrophages.Discussion: These findings offer innovative perspectives for the treatment of advanced renal carcinoma.</p
Uniform Small Graphene Oxide as an Efficient Cellular Nanocarrier for Immunostimulatory CpG Oligonucleotides
Graphene oxide (GO) has attracted
more and more attention as a promising nanomaterial in biomedical
research and applications. In this study, we explore the ability of
GO as nanocarrier for synthetic DNA strands. Immunostimulatory CpG
oligodeoxynucleotides (ODNs) are attached to Poly-l-Lysine
(PLL) functionalized, polydisperse GO, or uniform small GO (sGO) nanosheets.
Both types of GO-CpG ODN nanoconjugates can be delivered into murine
Raw264.7 macrophages and possess immunostimulatory activity, while
sGO-CpG appears to be a more efficient stimulator. In addition, sGO-CpG
nanosheets exhibit higher cellular uptake but better biocompatibility
compared to the larger GO-CpG counterpart. Furthermore, PLL functionalized
sGO-CpG has higher immunostimulatory activity than azide functionalized
sGO-CpG. Together, our studies provide evidence that sGO can be utilized
as an ideal intracellular nanocarrier for synthetic single-stranded
DNA, and sGO-PLL-CpG conjugates may serve as a potential proinflammatory
therapeutic tool
Interaction effect between the <i>IL4</i>, <i>IL13</i> and <i>IL4RA</i> genotypes among cases and controls.
a<p>SNPs were classified as wild-type genotype and heterozygote/homozygote genotypes. The wild-type genotypes of <i>IL4</i> C-590T, <i>IL13</i> C-1055T, <i>IL13</i> Arg130Gln, <i>IL4RA</i> Ile50Val, <i>IL4RA</i> Ser478Pro, and <i>IL4RA</i> Gln551Arg were TT, CC, GG, CC, TT, and AA, respectively, and the heterozygote/homozygote genotypes of these six SNPs were CT/CC, CT/TT, AG/AA, CT/TT, CT/CC, and AG/GG, respectively.</p>b<p>Adjusted for age and sex in logistic regression model.</p
Distribution of selected variables among cases and controls.
a<p>Serum levels of total IgE (kU/L) and specific IgE (kUA/L) were log transformed to normalize the distribution.</p