•Thermal conductivity(TC) of 3C-SiC was studied by (non-)/Equilibrium MD.•Effect of temperature and cascade collision on conductivity was explored.•Results of Tersoff/zbl and MEAM interatomic ...potential were illustrated.•Multiple-phase simulation was used and 4 kinds of point defects was counted.•Cascade collision caused by a higher-energy atom can induce lower TC of 3C-SiC.
The cubic silicon carbide 3C-SiC, the significant nuclear material used to manufacture the nuclear fuel in High Temperature Gas-cooled Reactor (HTGR), operates under a high temperature and neutron flux condition. The effect of temperature and irradiation on thermal conductivity of 3C-SiC were investigated with the molecular dynamics method. The equilibrium and non-equilibrium methods were utilized to calculate the thermal conductivity of 3C-SiC and the results of tersoff/zbl and MEAM interatomic potential were compared. Exponential decay of thermal conductivity with increasing temperature was illustrated. The irradiation effect was simulated with a high-energy Si atom and subsequent cascade collision, a multiple-phase simulation procedure was employed and the number of four kinds of point defects was counted. Finally, a relatively smaller simulation cell was used to analyze the impact of the incident atom with various velocities on the thermal conductivity of 3C-SiC. The computed results showed the cascade collision, caused by a higher-energy atom, would induce the lower thermal conductivity of 3C-SiC.
Using the AV18 equation of state, we numerically calculate the structure of a neutron star in Rastall gravity. The results show that the parameter
λ
originated from Rastall gravity has a great effect ...on the mass and the radius of a neutron star. When
λ
=
1
, the Rastall equations of motion can be reduced to those in the general relativity. In terms of the stability condition for the Rastall equation of hydrostatic equilibrium,
λ
can be divided into two regions:
1
,
+
∞
)
and
(
−
∞
,
−
1
)
. In these two regions, the maximum mass and radius of a star increase with
λ
increasing. As
λ
is large enough in the range of
λ
⩾
1
, the maximum mass and radius tend towards 7.43
M
⊙
and 35.65 km. While
λ
is small enough in the range of
λ
<
−
1
, the maximum mass and radius are approximately 7.45
M
⊙
and 35.55 km. It is interesting that the upper maximum mass is 9.76
M
⊙
when
λ
tends to −1 and the lower maximum mass is 1.65
M
⊙
as
λ
=
1
. Furthermore, when
λ
≈
1.16
, there exist two neutron stars with the equal maximum mass, 1.92
M
⊙
, and different radii, 13.28 km and 22.85 km.
Prediction of the time-related traits of pebble flow inside pebble-bed HTGRs is of great significance for reactor operation and design. In this work, an image-driven approach with the aid of a ...convolutional neural network (CNN) is proposed to predict the remaining time of initially loaded pebbles and the time interval of paired flow images of the pebble bed. Two types of strategies are put forward: one is adding FC layers to the classic classification CNN models and using regression training, and the other is CNN-based deep expectation (DEX) by regarding the time prediction as a deep classification task followed by softmax expected value refinements. The current dataset is obtained from the discrete element method (DEM) simulations. Results show that the CNN-aided models generally make satisfactory predictions on the remaining time with the determination coefficient larger than 0.99. Among these models, the VGG19+DEX performs the best and its CumScore (proportion of test set with prediction error within 0.5s) can reach 0.939. Besides, the remaining time of additional test sets and new cases can also be well predicted, indicating good generalization ability of the model. In the task of predicting the time interval of image pairs, the VGG19+DEX model has also generated satisfactory results. Particularly, the trained model, with promising generalization ability, has demonstrated great potential in accurately and instantaneously predicting the traits of interest, without the need for additional computational intensive DEM simulations. Nevertheless, the issues of data diversity and model optimization need to be improved to achieve the full potential of the CNN-aided prediction tool.
•An image-driven approach of CNN + DEM is proposed for pebble-flow in HTGRs.•CNN + DEX outperforms corresponding regression models on evaluation metrics.•VGG19+DEX model performs the best on test sets with the CumScore of 0.939.•Promising results prove the generalization ability of the VGG19+DEX.•As a potential real-time prediction tool, the trained model is more efficient than DEM.
In this study, we used RNA sequencing (RNA-seq) to analyze and compare bulk cell samples from wild-type (WT) dermal mesenchymal stem cells (DMSCs) (n = 3) and
Prx II
knockout DMSCs (n = 3). The ...purpose of the study was to elucidate the role of
Prx II
on allogeneic immune rejection of transplanted DMSCs. The results revealed differential expression of 472 genes (176 up-regulated and 296 down-regulated;
p
≤ 0.05) between the PrxII
+/+
(WT) and PrxII
−/−
sample groups. When highly regulated genes were categorized according to the Gene Ontology (GO) molecular function classification and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, the PrxII
−/−
samples showed a robust downward trend in allograft rejection. The study identified 43 all immunologically rejected differentially expressed genes, of which 41 showed lower expression in the PrxII
−/−
vs. PrxII
+/+
(WT) samples. These findings suggest that
Prx II
gene knockout may down-regulate the allograft rejection that occurs during DMSCs transplantation and improve the survival rate of DMSCs in the host. This study provides a new perspective on the clinical treatment of stem cell transplantation.
Hit, Lead & Candidate Discovery
It is reported that 1,4‐naphthoquinones and their derivatives have potent antitumor activity in various cancers, although their clinical application is limited by ...observed side effects. To improve the therapeutic efficacy of naphthoquinones in the treatment of cancer and to reduce side effects, we synthesized a novel naphthoquinone derivative, 2‐(naphthalene‐2‐thio)‐5,8‐dimethoxy‐1,4‐naphthoquinone (NTDMNQ). In this study, we explored the effects of NTDMNQ on apoptosis in gastric cancer cells with a focus on reactive oxygen species (ROS) production. Our results demonstrated that NTDMNQ exhibited the cytotoxic effects on gastric cancer cells in a dose‐dependent manner. NTDMNQ significantly induced mitochondrial‐related apoptosis in AGS cells and increased the accumulation of ROS. However, pre‐treatment with N‐acetyl‐L‐cysteine (NAC), an ROS scavenger, inhibited the NTDMNQ‐induced apoptosis. In addition, NTDMNQ increased the phosphorylation of p38 kinase and c‐Jun N‐terminal kinase (JNK) and decreased the phosphorylation of extracellular signal‐regulated kinase (ERK), protein kinase B (Akt), and Signal Transducer and Activator of Transcription 3 (STAT3); these effects were blocked by mitogen‐activated protein kinase (MAPK) inhibitor and NAC. Taken together, the present findings indicate that NTDMNQ‐induced gastric cancer cell apoptosis via ROS‐mediated regulation of the MAPK, Akt, and STAT3 signaling pathways. Therefore, NTDMNQ may be a potential treatment for gastric cancer as well as other tumor types.
Isoorientin (ISO) is a naturally occurring C‑glycosyl flavone that has various pharmacological properties, such as anti‑bacterial and anti‑inflammatory effects. However, its underlying molecular ...mechanisms in human lung cancer cells remain unknown. In the present study, the effects of ISO on the induction of apoptosis and relative molecular mechanisms in A549 human lung cancer cells were investigated. The results of Cell Counting Kit‑8 assay (CCK‑8) indicated that ISO exerted significant cytotoxic effects on 3 lung cancer cell lines, but had no obvious side‑effects on normal cells. Moreover, flow cytometry and western blot analysis revealed that ISO induced mitochondrial‑dependent apoptosis by reducing mitochondrial membrane potential. ISO also increased the expression levels of Bax, cleaved‑caspase‑3 (cle‑cas‑3) and poly(ADP‑ribose) polymerase (PARP; cle‑PARP), and decreased the expression levels of Bcl‑2 in A549 cells. Furthermore, ISO induced G2/M cell cycle arrest by decreasing the expression levels of cyclin B1 and CDK1/2, and increasing the expression levels of p21 and p27 in A549 cells. As the duration of ISO treatment increased, intracellular reactive oxygen species (ROS) levels in A549 cells also increased. However, pre‑treatment of the cells with the ROS scavenger, N‑acetylcysteine (NAC), inhibited ISO‑induced apoptosis. In addition, ISO increased the expression levels of p‑p38, p‑JNK and IκB‑α; and decreased the expression levels of p‑extracellular signal‑regulated kinase (ERK), p‑signal transducer and activator of transcription (STAT)3, p‑nuclear factor (NF)‑κB, NF‑κB and p‑IκB; these effects were induced by mitogen‑activated protein kinase (MAPK) inhibitors and blocked by NAC. Taken together, the results of the present study indicate that ISO induces the apoptosis of A549 lung cancer cells via the ROS‑mediated MAPK/STAT3/NF‑κB signaling pathway, and thus may be a potential drug for use in the treatment of lung cancer.
Lipoprotein lipase (LPL) deficiency is a monogenic lipid metabolism disorder biochemically characterized by hypertriglyceridemia (HTG) inherited in an autosomal recessive manner. Neonatal onset LPL ...deficiency is rare. The purpose of this study was to clarify the clinical features of neonatal LPL deficiency and to analyze the genetic characteristics of LPL gene.
In order to reach a definite molecular diagnose, metabolic diseases-related genes were sequenced through gene capture and next generation sequencing. Meanwhile, the clinical characteristics and follow-up results of the two newborns were collected and analyzed.
Three different mutations in the LPL gene were identified in the two newborns including a novel compound heterozygous mutation (c.347G > C and c.472 T > G) and a reported homozygous mutation (c.836 T > G) was identified. Interestingly, both the two neonatal onset LPL deficiency patients presented with suffered recurrent infection in the hyperlipidemia stage, which was not usually found in childhood or adulthood onset LPL deficiency patients.
The two novel mutaitons, c.347G > C and c.472 T > G, identified in this study were novel, which expanded the LPL gene mutation spectrum. In addition, suffered recurrent infection in the hyperlipidemia stage implied a certain correlation between immune deficiency and lipid metabolism abnormality. This observation further supplemented and expanded the clinical manifestations of LPL deficiency.
Cryptotanshinone (CT), isolated from the plant
, has been reported to have potential anticancer effects on human prostate and breast cancer cells. However, the mechanisms of action of CT on gastric ...cancer (GC) cells are not well understood. Here we investigated the antitumor effects of CT on GC cells and its possible molecular mechanism. We found CT suppressed viability of twelve GC cell lines in a dose-dependent manner. CT induced cell cycle arrest at the G2/M phase and mitochondrial apoptosis accompanying the accumulation of reactive oxygen species (ROS). Pretreatment with ROS inhibitor N-acetyl-L-cysteine (NAC) blocked CT-induced apoptosis. CT increased p-JNK and p-p38, and decreased p-ERK and p-STAT3 protein expression, these effects were prevented by NAC. Furthermore, a xenograft assay showed that CT significantly inhibited MKN-45 cell-induced tumor growth
by increasing expression of pro-apoptotic proteins (p-JNK, p-38 and cleaved-caspase-3) and reducing expression of anti-apoptotic proteins (p-ERK and p-STAT3) without adverse effects on nude mice weight. In conclusion, CT induced apoptosis and cell cycle arrest in GC cells via ROS-mediated MAPK and AKT signaling pathways, and this CT may be a useful compound for the developing anticancer agents for GC.
PDF
