45 research outputs found
Cytotoxic coumaronochromones from the inflorescences of <i>Celosia cristata</i>
<p>Investigation on the MeOH extracts of the inflorescences of <i>Celosia cristata</i> led to the isolation of two new coumaronochromones, cristatone I (<b>1</b>) and cristatone II (<b>2</b>), along with three known flavones (<b>3</b>–<b>5</b>). Their structures were elucidated on the basis of spectroscopic analyses. Compounds <b>1</b>–<b>5</b> were tested for their cytotoxic activity against HeLa and BGC-823 cancer cell lines, of which cristatone II (<b>2</b>) showed interesting activity with the IC<sub>50</sub> value of 23.82 μM.</p
Reduced Graphene Oxide-Based Solid-Phase Extraction for the Enrichment and Detection of microRNA
MicroRNAs
(miRNAs) are endogenous molecules with regulatory functions.
The purification and enrichment of miRNA are essential for its precise
and sensitive detection. miRNA isolated using commercial kits contains
abundant interfering RNAs, and the concentration of miRNA may not
be adequate for detection. Herein, we prepared a reduced graphene
oxide (rGO)-based magnetic solid-phase extraction material for the
enrichment and ultrasensitive detection of miRNA from intricate nucleic
acid solutions. <i>In situ</i> reverse transcription (RT)
was developed as the most efficient approach to desorb miRNA from
rGO among the methods that are compatible for the subsequent amplification
reported thus far. Additionally, rolling circle amplification and
qPCR were used to detect let-7a with a decrease of the limit of detection
by 24.7- and 31.3-fold, respectively. This material was also successfully
used to extract and detect miRNA from total RNA isolated from human
plasma. Our results show that the material prepared in this study
has the potential for cancer biopsy in clinics and the discovery of
new miRNAs in scientific research
sj-rar-1-jim-10.1177_1045389X221131806 – Supplemental material for A novel laparoscopic surgical robot (LSR) based on double-leg ultrasonic motor (DUM)
Supplemental material, sj-rar-1-jim-10.1177_1045389X221131806 for A novel laparoscopic surgical robot (LSR) based on double-leg ultrasonic motor (DUM) by Qing Lu, Zhijun Sun, He Yan, Jiacheng Zhang, Jialiang Zhang and Jianlin Yang in Journal of Intelligent Material Systems and Structures</p
sj-rar-2-jim-10.1177_1045389X221131806 – Supplemental material for A novel laparoscopic surgical robot (LSR) based on double-leg ultrasonic motor (DUM)
Supplemental material, sj-rar-2-jim-10.1177_1045389X221131806 for A novel laparoscopic surgical robot (LSR) based on double-leg ultrasonic motor (DUM) by Qing Lu, Zhijun Sun, He Yan, Jiacheng Zhang, Jialiang Zhang and Jianlin Yang in Journal of Intelligent Material Systems and Structures</p
Additional file 2: of Evaluation of the population structure and genetic diversity of Plasmodium falciparum in southern China
Allele frequencies at 13 microsatellite loci of the seven Plasmodium falciparum populations in the South China
Additional file 5: of Evaluation of the population structure and genetic diversity of Plasmodium falciparum in southern China
Selected marker sets to differentiate Plasmodium falciparum isolates between Yunnan and Hainan provinces with high accuracy
Selenophene-Incorporated Quaterchalcogenophene-Based Donor–Acceptor Copolymers To Achieve Efficient Solar Cells with <i>J</i><sub>sc</sub> Exceeding 20 mA/cm<sup>2</sup>
Three selenophene-incorporated
quaterchalcogenophene-based donor–acceptor
copolymers PFBT2Th2Se, PFBT2Se2Th, and PFBT4Se are designed and synthesized.
To systematically fine-tune the molecular properties and investigate
the chalcogen effect, PFBT2Th2Se and PFBT2Se2Th hybridize two thiophenes
and two selenophenes as the donor with different isomeric main-chain
placement while thiophene-free PFBT4Se uses quaterselenophene as the
donor. On account of the selenophene’s advantageous features
such as higher quinoidal population and higher molecular polarizability,
the three polymers show good light-harvesting ability, strong intermolecular
interactions, high crystallinity, and high charge mobilities. Bulk-heterojunction
solar cells incorporating these selenophene-containing polymers have
exhibited promising photovoltaic performance with impressive current
densities over 20 mA/cm<sup>2</sup>. The device with the PFBT2Se2Th:PC<sub>71</sub>BM blend showed a PCE of 9.02% with a <i>J</i><sub>sc</sub> of 21.02 mA/cm<sup>2</sup>. In addition, the device using
quaterselenophene-based PFBT4Se:PC<sub>71</sub>BM blend exhibited
a PCE of 8.92% with a superior <i>J</i><sub>sc</sub> of
22.63 mA/cm<sup>2</sup> which represents one of the highest current
densities from polymer:fullerene-based solar cells reported in the
literature
Surface Decoration on Polymeric Gate Dielectrics for Flexible Organic Field-Effect Transistors via Hydroxylation and Subsequent Monolayer Self-Assembly
A simple
photochemical reaction based on confined photocatalytic oxidation
(CPO) treatment and hydrolysis was employed to efficiently convert
C–H bonds into C–OH groups on polymeric material surfaces,
followed by investigation of monolayer self-assembly decoration on
polymeric dielectrics via chemical bonding for the organic field-effect
transistors (OFETs) applications. This method is a low temperature
process and has negligible etching effect on polymeric dielectric
layers. Various types of self-assembled monolayers have been tested
and successfully attached onto the hydroxylated polymeric dielectric
surfaces through chemical bonding, ensuring the stability of decorated
functional films during the subsequent device fabrication consisting
of solution processing of the polymer active layer. With the surface
decoration of functional groups, both n-type and p-type polymers exhibit
enhanced carrier mobilities in the unipolar OFETs. In addition, enhanced
and balanced mobilities are obtained in the ambipolar OFETs with the
blend of polymer semiconductors. The anchored self-assembled monolayers
on the dielectric surfaces dramatically preclude the solvent effect,
thus enabling an improvement of carrier mobility up to 2 orders of
magnitude. Our study opens a way of targeted modifications of polymeric
surfaces and related applications in organic electronics
Put Your Backbone into It: Excited-State Structural Relaxation of PffBT4T-2DT Conducting Polymer in Solution
Conformational and
energetic disorder in organic semiconductors
reduces charge and exciton transport because of the structural defects,
thus reducing the efficiency in devices such as organic photovoltaics
and organic light-emitting diodes. The main structural heterogeneity
is because of the twisting of the polymer backbone that occurs even
in polymers that are mostly crystalline. Here, we explore the relationship
between polymer backbone twisting and exciton delocalization by means
of transient absorption spectroscopy and density functional theory
calculations. We study the PffBT4T-2DT polymer which has exhibited
even higher device efficiency with nonfullerene acceptors than the
current record breaking PCE11 polymer. We determine the driving force
for planarization of a polymer chain caused by excitation. The methodology
is generally applicable and demonstrates a higher penalty for nonplanar
structures in the excited state than in the ground state. This study
highlights the morphological and electronic changes in conjugated
polymers that are brought about by excitation
Study on the Antifungal Activity and Potential Mechanism of Natamycin against Colletotrichum fructicola
In this investigation, the antifungal activity, its influence
on
the quality of apples, and the molecular mechanism of natamycin against Colletotrichum fructicola were systematically explored.
Our findings indicated that natamycin showed significant inhibition
against C. fructicola. Moreover, it
efficaciously maintained the apple quality by modulating the physicochemical
index. Research on the antifungal mechanism showed that natamycin
altered the mycelial microstructure, disrupted the plasma membrane
integrality, and decreased the ergosterol content of C. fructicola. Interestingly, the exogenous addition
of ergosterol weakened the antifungal activity of natamycin. Importantly,
natamycin markedly inhibited the expression of Cyp51A and Cyp51B genes in C. fructicola, which was contrary to the results obtained after treatment with
triazole fungicide flusilazole. All these results exhibited sufficient
proof that natamycin had enormous potential to be conducive as a promising
biopreservative against C. fructicola on apples, and these findings will advance our knowledge on the
mechanism of natamycin against pathogenic fungi