31 research outputs found
Nickel Sulfide Freestanding Holey Films as Air-Breathing Electrodes for Flexible Zn–Air Batteries
In this work, a combination
of bottom-up electrochemical deposition
and top-down electrochemical etching strategies followed by a subsequent
sulfuration treatment was employed to rationally synthesize a nickel
sulfide (NiS<sub><i>x</i></sub>) freestanding holey film
(FHF). Owing to the holey structure along with the optimal electrochemically
active surface area and active sites, the as-prepared NiS<sub><i>x</i></sub> FHF showed an impressive bifunctional electrocatalytic
performance toward both oxygen evolution and reduction reactions.
The holey and freestanding features provide the NiS<sub><i>x</i></sub> FHF with promising characteristics to be used as an ideal
air-breathing cathode in flexible Zn–air batteries (ZABs).
As a proof-of-concept, the rationally designed NiS<sub><i>x</i></sub> FHF achieved remarkable rechargeability and flexibility in
a ZAB configuration
Additional file 1 of A hidden Markov tree model for testing multiple hypotheses corresponding to Gene Ontology gene sets
Supplementary Material. Details of deterministic annealing and additional simulation result. (PDF 152 kb
Oxidation as a Facile Strategy To Reduce the Surface Charge and Toxicity of Polyethyleneimine Gene Carriers
Polyethyleneimine
(PEI) is widely regarded as one of the most efficient non-viral transfection
agents commercially available. However, a key concern is its pronounced
cytotoxicity, ascribed mainly to its high amine content and cationic
charge density. Significant past efforts to mitigate its toxicity
usually involved lengthy synthetic procedures. We now propose a simple
strategy using hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) to oxidize
the amine groups. PEI/DNA complexes were first formed before some
amine groups were removed with H<sub>2</sub>O<sub>2</sub>. This reduced
surface charge while the remaining cationic charges still allowed
for efficient transfection. The DNA was not damaged and remained bound
after oxidation. Furthermore, H<sub>2</sub>O<sub>2</sub> was quantitatively
removed with sodium pyruvate prior to cell culture. Oxidized complexes
caused no cytotoxicity even at high polymer concentrations. Compared
to non-oxidized complexes used at subtoxic doses, oxidized complexes
mediated significantly more GFP expression. A key strength of this
approach is its simplicity as it involves only simple mixing of solutions.
This strategy promises to further realize the potential of using PEI
for the delivery of nucleic acids or other cargos
The Mechanism and Fine-Tuning of Chiral Plexcitons in the Strong Coupling Regime
Chiral plexcitons, produced by the
strong interaction
between plasmonic
nanocavities and chiral molecules, can provide a promising direction
for controlling chiroptical responses on the nanoscale. Here, we reveal
the chiral origin and electromagnetic hybridization process in chiral
strongly coupled systems. The mechanism and unique advantages of chiral
plexcitons for fine-tuning circular dichroism (CD) responses are demonstrated,
providing a rule for controlling chiral light–matter interactions
in complex chiral nanosystems. Furthermore, we experimentally demonstrate
the fine-tuning of chiral plexcitons in hybrid systems consisting
of plasmonic nanoparticles and chiral J-aggregates. Continuous and
precise tuning of the CD resonance positions was successfully achieved
in a given structure. Compared with the previous work, the CD spectral
tuning accuracy has been improved by an order of magnitude, which
can reach the level of 1 nm. Our findings provide a feasible strategy
and theoretical basis for accurately controlling chirality in multiple
dimensions
Supplemental Data 1
Stratigraphic information and locality of Catenipora specimens for morphometric analysis
An Asymmetric Supercapacitor with Both Ultra-High Gravimetric and Volumetric Energy Density Based on 3D Ni(OH)<sub>2</sub>/MnO<sub>2</sub>@Carbon Nanotube and Activated Polyaniline-Derived Carbon
Development of a
supercapacitor device with both high gravimetric and volumetric energy
density is one of the most important requirements for their practical
application in energy storage/conversion systems. Currently, improvement
of the gravimetric/volumetric energy density of a supercapacitor is
restricted by the insufficient utilization of positive materials at
high loading density and the inferior capacitive behavior of negative
electrodes. To solve these problems, we elaborately designed and prepared
a 3D core–shell structured NiÂ(OH)<sub>2</sub>/MnO<sub>2</sub>@carbon nanotube (CNT) composite via a facile solvothermal process
by using the thermal chemical vapor deposition grown-CNTs as support.
Owing to the superiorities of core–shell architecture in improving
the service efficiency of pseudocapacitive materials at high loading
density, the prepared NiÂ(OH)<sub>2</sub>/MnO<sub>2</sub>@CNT electrode
demonstrated a high capacitance value of 2648 F g<sup>–1</sup> (1 A g<sup>–1</sup>) at a high loading density of 6.52 mg
cm<sup>–2</sup>. Coupled with high-performance activated polyaniline-derived
carbon (APDC, 400 F g<sup>–1</sup> at 1 A g<sup>–1</sup>), the assembled NiÂ(OH)<sub>2</sub>/MnO<sub>2</sub>@CNT//APDC asymmetric
device delivered both high gravimetric and volumetric energy density
(126.4 Wh kg<sup>–1</sup> and 10.9 mWh cm<sup>–3</sup>, respectively), together with superb rate performance and cycling
lifetime. Moreover, we demonstrate an effective approach for building
a high-performance supercapacitor with high gravimetric/volumetric
energy density
Enhancing Electron Transfer and Electrocatalytic Activity on Crystalline Carbon-Conjugated g‑C<sub>3</sub>N<sub>4</sub>
Carbon
nitride (g-C<sub>3</sub>N<sub>4</sub>) materials are electro-activated
for oxygen reduction (ORR) and oxygen evolution (OER) reactions when
they are supported by conductive carbons. However, the electrocatalytic
process on semiconductor-based heterostructures such as carbon-supported
g-C<sub>3</sub>N<sub>4</sub> still suffers from a huge energy loss
because of poor electron mobility. Here, we demonstrated a concept
that the conjugation of g-C<sub>3</sub>N<sub>4</sub> with crystalline
carbon can improve the in-plane electron mobility and make interior
triazine units more electro-active for ORR and OER. As a result, the
Co metal coordinated g-C<sub>3</sub>N<sub>4</sub> with crystalline
carbons (Co–C<sub>3</sub>N<sub>4</sub>/C) showed a remarkable
electrocatalytic performance toward both ORR and OER. For example,
it displayed an onset potential of 0.95 V for ORR and an overpotential
of 1.65 V for OER at 10 mA cm<sup>–2</sup>, which are comparable
and even better than those of benchmark Pt, RuO<sub>2</sub>, and other
carbon nitride-based electrocatalysts. As a proof-of-concept application,
we employed this catalyst as an air electrode in the rechargeable
aluminum-air battery, which showed more rechargeable and practicable
than those of Pt/C and RuO<sub>2</sub> catalysts in two-electrode
coin battery. The characterization results identified that the good
performance of Co–C<sub>3</sub>N<sub>4</sub>/C was primarily
attributed to the enhanced in-plane electron mobility by crystalline
carbon conjugation and the Co-coordinated g-C<sub>3</sub>N<sub>4</sub> along with nitrogen-doped carbons
Detection of G‑Quadruplex Structures Formed by G‑Rich Sequences from Rice Genome and Transcriptome Using Combined Probes
Putative
G-quadruplex (G4) forming sequences (PQS) are highly prevalent
in the genome and transcriptome of various organisms and are considered
as potential regulation elements in many biological processes by forming
G4 structures. The formation of G4 structures highly depends on the
sequences and the environment. In most cases, it is difficult to predict
G4 formation by PQS, especially PQS containing G2 tracts. Therefore,
the experimental identification of G4 formation is essential in the
study of G4-related biological functions. Herein, we report a rapid
and simple method for the detection of G4 structures by using a pair
of complementary reporters, hemin and BMSP. This method was applied
to detect G4 structures formed by PQS (DNA and RNA) searched in the
genome and transcriptome of Oryza sativa. Unlike most of the reported G4 probes that only recognize part
of G4 structures, the proposed method based on combined probes positively
responded to almost all G4 conformations, including parallel, antiparallel,
and mixed/hybrid G4, but did not respond to non-G4 sequences. This
method shows potential for high-throughput identification of G4 structures
in genome and transcriptome. Furthermore, BMSP was observed to drive
some PQS to form more stable G4 structures or induce the G4 formation
of some PQS that cannot form G4 in normal physiological conditions,
which may provide a powerful molecular tool for gene regulation
Results of haplotypes formed by rs5745718, rs17427817, and rs3735520 at HGF locus in PACG patients and controls in the Chinese Han population.
<p>Pc = Bonferroni corrected P; OR = odds ratio; 95% CI = 95% confidence interval.</p
Primers of HGF SNPs and restriction enzymes used for FRLP analysis.
<p>Primers of HGF SNPs and restriction enzymes used for FRLP analysis.</p