An energy conservative scheme is proposed for the regularized long wave (RLW) equation. The integral method with variational limit is used to discretize the spatial derivative and the finite ...difference method is used to discretize the time derivative. The energy conservation of the scheme and existence of the numerical solution are proved. The convergence of the order
O
(
h
2
+
τ
2
) and unconditional stability are also derived. Numerical examples are carried out to verify the correctness of the theoretical analysis.
In the artificial breeding of
(Euphrasen, 1788), female fish spawn before male release sperm, which indicates rapid ovarian development. In fish, aromatase is responsible for converting androgens ...into estrogens and estrogen plays a crucial role in ovarian development. In this study, we aimed to investigate the potential role of brain-type and ovarian-type aromatase to study the rapid ovarian development mechanism. The results showed that
was mainly expressed in the ovary and could be classified as the ovarian type, whereas
could be considered as the brain type for its expression was mainly in the brain. During ovarian development, the expression of
in the ovary significantly increased from stage IV to stage V and Cyp19a1a signals were present in the follicle cells, while
expression in the pituitary gland decreased from stage IV to stage V. To further investigate the function of Cyp19a1a, recombinant Cyp19a1a (rCyp19a1a) was produced and specific anti-Cyp19a1a antiserum was obtained. The expressions of
,
(
), and
(
) were significantly upregulated in the presence of rCyp19a1a. Meanwhile,
was expressed significantly after E2 treatment in both ovarian and testicular tissue culture. Taken together, we found two forms of aromatase in silver pomfret. The ovarian-type aromatase might play an important role in ovarian differentiation and maturation, and participate in E2 synthesis through co-regulation with
The brain-type aromatase
might be involved in the regulation of both brain and gonadal development.
In the artificial breeding of Pampus argenteus (Euphrasen, 1788), female fish spawn before male release sperm, which indicates rapid ovarian development. In fish, aromatase is responsible for ...converting androgens into estrogens and estrogen plays a crucial role in ovarian development. In this study, we aimed to investigate the potential role of brain-type and ovarian-type aromatase to study the rapid ovarian development mechanism. The results showed that cyp19a1a was mainly expressed in the ovary and could be classified as the ovarian type, whereas cyp19a1b could be considered as the brain type for its expression was mainly in the brain. During ovarian development, the expression of cyp19a1a in the ovary significantly increased from stage IV to stage V and Cyp19a1a signals were present in the follicle cells, while cyp19a1b expression in the pituitary gland decreased from stage IV to stage V. To further investigate the function of Cyp19a1a, recombinant Cyp19a1a (rCyp19a1a) was produced and specific anti-Cyp19a1a antiserum was obtained. The expressions of cyp19a1a, estrogen receptors 2 alpha (esr2a), and androgen receptor alpha (arα) were significantly upregulated in the presence of rCyp19a1a. Meanwhile, cyp19a1a was expressed significantly after E2 treatment in both ovarian and testicular tissue culture. Taken together, we found two forms of aromatase in silver pomfret. The ovarian-type aromatase might play an important role in ovarian differentiation and maturation, and participate in E2 synthesis through co-regulation with esr2a. The brain-type aromatase cyp19a1b might be involved in the regulation of both brain and gonadal development.
The development of cost-effective, robust, and durable electrocatalysts to replace the expensive Pt-based catalysts towards oxygen reduction reaction (ORR) is the trending frontier research topic in ...renewable energy and electrocatalysis. Particular attention has been paid to metal-nitrogen-carbon (M-N-C) single atom catalysts (SACs) due to their maximized atom utilization efficiency, biomimetic active site, and distinct electronic structure. More importantly, their catalytic properties can be further tailored by rationally regulating the microenvironment of active sites (i.e., M–N coordination number, heteroatom doping and substitution. Herein, we present a comprehensive summary of the recent advancement in the microenvironment regulation of M-N-C SACs towards improved ORR performance. The coordination environment manipulation regarding central metal and coordinated atoms is first discussed, focusing on the structure—function relationship. Apart from the near-range coordination, long-range substrate modulation including heteroatom doping, defect engineering is discussed as well. Besides, the synergy mechanism of nanoparticles and single atom sites to tune the electron cloud density at the active sites is summarized. Finally, we provide the challenges and outlook of the development of M-N-C SACs.
Hyaluronic acid (HA)-based hydrogels are widely used in biomedical applications due to their excellent biocompatibility. HA can be Ultraviolet (UV)-crosslinked by modification with methacrylic ...anhydride (HA-MA) and crosslinked by modification with 3,3′-dithiobis(propionylhydrazide) (DTP) (HA-SH) via click reaction. In the study presented in this paper, a 3D-bioprinted, double-crosslinked, hyaluronic-acid-based hydrogel for wound dressing was proposed. The hydrogel was produced by mixing HA-MA and HA-SH at different weight ratios. The rheological test showed that the storage modulus (G’) of the HA-SH/HA-MA hydrogel increased with the increase in the HA-MA content. The hydrogel had a high swelling ratio and a high controlled degradation rate. The in vitro degradation test showed that the hydrogel at the HA-SH/HA-MA ratio of 9:1 (S9M1) degraded by 89.91% ± 2.26% at 11 days. The rheological performance, drug release profile and the cytocompatibility of HA-SH/HA-MA hydrogels with loaded Nafcillin, which is an antibacterial drug, were evaluated. The wound dressing function of this hydrogel was evaluated by Live/Dead staining and CCK-8 assays. The foregoing results imply that the proposed HA-SH/HA-MA hydrogel has promise in wound repair applications.
The recently developed DNA−gold nanoparticle (DNA−GNP) biobarcode assay provides polymerase chain reaction (PCR)-like sensitivity for nucleic acid and protein targets without a need for enzymatic ...amplification. However, application of the conventional assay is challenged by its complex, expensive, time-consuming, and labor-intense procedure. Herein, we present a new electrochemiluminescence (ECL) biobarcode method based on cysteamine−GNP conjugates. In this strategy, an ECL nanoprobe is fabricated that relies on GNP that is modified with tris-(2,2′-bipyridyl) ruthenium (TBR) labeled cysteamine to boost ECL signals and single strand DNA for target recognition. Specifically, a sandwich complex that consists of a biotin labeled capture probe, target DNA, and cysteamine−GNP conjugate is captured by magnetic microparticles (MMPs) and subsequently identified by the ECL signals from loaded TBR. With the use of the developed probe, a limit of detection as low as 100 fM can be achieved and the assay exhibits excellent selectivity for single-mismatched DNA detection even in human serum. The proposed ECL based method should have wide applications in diagnosis of genetic diseases due to its high sensitivity, simplicity, and low cost.
As the most ordinary metabolic disorder during pregnancy, gestational diabetes mellitus (GDM) has become a severe risk for the health of both pregnant female and fetus. Astragaloside IV (AS-IV) is ...the dominant active component in Astragalus membranaceus. It has been proved that AS-IV has anti-inflammation and immune-regulation function. We aimed to demonstrate the function of AS-IV in the therapy of GDM and the molecular mechanism in this process.
C57BL/KsJ-Lepdb/+ female mice were used as GDM model. The mRNA levels of relative genes in this research were detected by qRT-PCR. The protein levels of relative genes were analyzed by western blot. Serum concentration of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were analyzed by ELISA.
Glucose and insulin levels in GDM mice model were decreased by AS-IV treatment. AS-IV down-regulated the expression of inflammatory gene IL-6 and TNF-α in GDM mice model. AS-IV treatment inhibited the expression of NLR family pyrin domain containing-3 (NLRP3) inflammasome relative proteins in the pancreas of GDM mice.
This study demonstrated that AS-IV treatment has an effective therapeutic function of GDM in mice model through the inhibition of NLRP3 inflammasome in the pancreas.
Shape memory polymers (SMPs), as a class of intelligent materials, have shown great potential in biomedical and robotic fields. Although efforts have been made to design and fabricate SMPs in the ...past decades, most of the SMPs are not suitable for use in the human body due to their unpleasant triggering conditions. Furthermore, it is of great importance to diversify the shape memory effect (SME) of SMPs to extend their applications. In this work, through thiol-ene chemistry, SMPs based on random cross-linked hydrophobic polytetrahydrofuran (PTHF) and hydrophilic poly(ethylene glycol) (PEG) oligomers were facilely fabricated. These SMPs showed a body temperature-triggered two-way SME with a reversible strain of up to 25.2%. Besides, the SMPs exhibited a good body temperature- and water-triggered one-way triple-SME. These features bestowed the polymers with a bright future in biomedical applications. Polymer P60-G40 was applied as a new type of esophageal stent, and the in vitro assessment showed that the stent was adjustable, self-expandable, and had the ability to release drugs, which were attributed to the one-way triple-SME and two-way SME.
Electrochemical production of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (ORR) process is emerging as a promising alternative method to the conventional anthraquinone ...process. To realize high‐efficiency H2O2 electrosynthesis, robust and low cost electrocatalysts have been intensively pursued, among which Co−based catalysts attract particular research interests due to the earth‐abundance and high selectivity. Here, we provide a comprehensive review on the advancement of Co−based electrocatalyst for H2O2 electroproduction. The fundamental chemistry of 2‐electron ORR is discussed firstly for guiding the rational design of electrocatalysts. Subsequently, the development of Co−based electrocatalysts involving nanoparticles, compounds and single atom catalysts is summarized with the focus on active site identification, structure regulation and mechanism understanding. Moreover, the current challenges and future directions of the Co−based electrocatalysts are briefly summarized in this review.
In recent years, more and more attention has been paid to the production of hydrogen peroxide (H2O2) by 2‐electron oxygen reduction reaction (ORR). Among them, Co−based catalysts have been widely studied for the selective production of H2O2 by 2‐electron ORR. Here, this review focuses on the mechanism of 2‐electron ORR from the perspective of kinetics and thermodynamics and summarizes the research progress of Co−based catalysts including Co molecular catalysts, Co nanoparticles, Co compounds, and Co single atom catalysts. It was demonstrated that Co−based catalysts had exhibited great selectivity towards 2‐electron ORR. Finally, we also discuss the challenges faced by various types of catalysts.