Efficient energy transport throughout conical implosions.

The double-cone ignition (DCI) scheme has been proposed as one of the alternative approaches to inertial confinement fusion, based on direct-drive and fast-ignition, in order to reduce the requirement for the driver energy. To evaluate the conical implosion energetics from the laser beams to the plasma flows, a series of experiments have been systematically conducted. The results indicate that 89%-96% of the laser energy was absorbed by the target, with moderate stimulated Raman scatterings. Here 2%-6% of the laser energy was coupled into the plasma jets ejected from the cone tips, which was mainly restricted by the mass reductions during the implosions inside the cones. The supersonic dense jets with a Mach number of 4 were obtained, which is favorable for forming a high-density, nondegenerated plasma core after the head-on collisions. These findings show encouraging results in terms of energy transport of the conical implosions in the DCI scheme.

The E3 ligase TRIM7 suppresses the tumorigenesis of gastric cancer by targeting SLC7A11.

Tripartite motif-containing protein 7 (TRIM7), as an E3 ligase, plays an important regulatory role in various physiological and pathological processes. However, the role of TRIM7 in gastric cancer (GC) is still undefined. Our study detected the expression of TRIM7 in clinical specimens and investigated the regulatory effect and molecular mechanism of TRIM7 on GC progression through in vitro and in vivo experiments. Our finding showed that TRIM7 was significantly downregulated in GC, and patients with high expression of TRIM7 showed long overall survival. Both in vitro and in vivo experiments showed that TRIM7 dramatically suppressed the malignant progression of GC. Further investigation showed that ferroptosis was the major death type mediated by TRIM7. Mechanistically, TRIM7 interacted with SLC7A11 through its B30.2/SPRY domain and promoted Lys48-linked polyubiquitination of SLC7A11, which effectively suppressing SLC7A11/GPX4 axis and inducing ferroptosis in GC cells. In vivo experiments and correlation analysis based on clinical specimens further confirmed that TRIM7 inhibited tumor growth through suppressing SLC7A11/GPX4 axis. In conclusion, our investigation demonstrated for the first time that TRIM7, as a tumor suppressor, induced ferroptosis via targeting SLC7A11 in GC, which provided a new strategy for the molecular therapy of GC by upregulating TRIM7.

New mechanistic insights of anti-obesity by sleeve gastrectomy-altered gut microbiota and lipid metabolism.

Background: The obesity epidemic has been on the rise due to changes in living standards and lifestyles. To combat this issue, sleeve gastrectomy (SG) has emerged as a prominent bariatric surgery technique, offering substantial weight reduction. Nevertheless, the mechanisms that underlie SG-related bodyweight loss are not fully understood. Methods: In this study, we conducted a collection of preoperative and 3-month postoperative serum and fecal samples from patients who underwent laparoscopic SG at the First Affiliated Hospital of Shandong First Medical University (Jinan, China). Here, we took an unbiased approach of multi-omics to investigate the role of SG-altered gut microbiota in anti-obesity of these patients. Non-target metabolome sequencing was performed using the fecal and serum samples. Results: Our data show that SG markedly increased microbiota diversity and Rikenellaceae, Alistipes, Parabacteroides, Bactreoidales, and Enterobacteraies robustly increased. These compositional changes were positively correlated with lipid metabolites, including sphingolipids, glycerophospholipids, and unsaturated fatty acids. Increases of Rikenellaceae, Alistipes, and Parabacteroide were reversely correlated with body mass index (BMI). Conclusion: In conclusion, our findings provide evidence that SG induces significant alterations in the abundances of Rikenellaceae, Alistipes, Parabacteroides, and Bacteroidales, as well as changes in lipid metabolism-related metabolites. Importantly, these changes were found to be closely linked to the alleviation of obesity. On the basis of these findings, we have identified a number of microbiotas that could be potential targets for treatment of obesity.

Bile acids inhibit ferroptosis sensitivity through activating farnesoid X receptor in gastric cancer cells.

BACKGROUND: Gastric cancer (GC) is associated with high mortality rates. Bile acids (BAs) reflux is a well-known risk factor for GC, but the specific mechanism remains unclear. During GC development in both humans and animals, BAs serve as signaling molecules that induce metabolic reprogramming. This confers additional cancer phenotypes, including ferroptosis sensitivity. Ferroptosis is a novel mode of cell death characterized by lipid peroxidation that contributes universally to malignant progression. However, it is not fully defined if BAs can influence GC progression by modulating ferroptosis. AIM: To reveal the mechanism of BAs regulation in ferroptosis of GC cells. METHODS: In this study, we treated GC cells with various stimuli and evaluated the effect of BAs on the sensitivity to ferroptosis. We used gain and loss of function assays to examine the impacts of farnesoid X receptor (FXR) and BTB and CNC homology 1 (BACH1) overexpression and knockdown to obtain further insights into the molecular mechanism involved. RESULTS: Our data suggested that BAs could reverse erastin-induced ferroptosis in GC cells. This effect correlated with increased glutathione (GSH) concentrations, a reduced GSH to oxidized GSH ratio, and higher GSH peroxidase 4 (GPX4) expression levels. Subsequently, we confirmed that BAs exerted these effects by activating FXR, which markedly increased the expression of GSH synthetase and GPX4. Notably, BACH1 was detected as an essential intermediate molecule in the promotion of GSH synthesis by BAs and FXR. Finally, our results suggested that FXR could significantly promote GC cell proliferation, which may be closely related to its anti-ferroptosis effect. CONCLUSION: This study revealed for the first time that BAs could inhibit ferroptosis sensitivity through the FXR-BACH1-GSH-GPX4 axis in GC cells. This work provided new insights into the mechanism associated with BA-mediated promotion of GC and may help identify potential therapeutic targets for GC patients with BAs reflux.

Safety assessment of sand casting explosion accidents by testing cavity pressure of the sand mold to protect employee health.

Excessive cavity pressure may result in a sand casting explosion, and corresponding measures should be adopted to prevent these consequences. In this study, the pressure variations in the cavity were first investigated based upon on-site testing by taking the resin contents into consideration, and then the evolution characteristics of sand casting explosion accidents were analyzed in depth by system dynamics, chaos theory, and the bow-tie model. When the resin contents are 1.3 wt%, 1.4 wt%, and 1.5 wt%, the pressures of the gas vent increase by 27.0 Pa, 32.8 Pa, and 35.6 Pa, respectively. To reduce the pressure of the cavity, the resin content should be reduced. The evolutionary process of sand casting explosion accidents has a noticeable butterfly effect and randomness, whose occurrence is comprehensively affected by human, object, environment, management and emergency subsystems. The leading causes of sand casting explosion accidents mainly include the extensive gas evolution characteristics of foundry sand, cavity exhaust blockage, and inadequate safety monitoring. The leading consequences of sand casting explosion accidents mainly include casualties, secondary disasters, and social panic. The implications of these findings concerning sand casting explosion accidents can be regarded as the foundation for accident prevention in practice.

Gentiopicroside inhibits the progression of gastric cancer through modulating EGFR/PI3K/AKT signaling pathway.

BACKGROUND: This study was designed to clarify the function and potential mechanism of gentiopicroside (GPS) in regulating the malignant progression of gastric cancer (GC) through in vitro cellular experiments and in vivo animal models. METHODS: AGS and HGC27 cells were divided into control group and GPS treatment groups (50 µM and 100 µM). Then, the cellular proliferation, colony formation, migration, invasion, and apoptosis were detected, respectively. Transmission electron microscope (TEM) was used to observe the mitochondrial changes, and the mitochondrial membrane potential (MMP) was determined using the JC-1 commercial kit. Network pharmacology analysis was utilized to screen the potential molecule that may be related to the GPS activity on GC cells, followed by validation tests using Western blot in the presence of specific activator. In addition, xenografted tumor model was established using BALB/c nude mice via subcutaneous injection of HGC27 cells, along with pulmonary metastasis model. Then, the potential effects of GPS on the tumor growth and metastasis were detected by immunohistochemistry (IHC) and HE staining. RESULTS: GPS inhibited the proliferation, invasion and migration of GC cell lines in a dose-dependent manner. Besides, it could induce mitochondrial apoptosis. Epidermal growth factor receptor (EGFR) may be a potential target for GPS action in GC by network pharmacological analysis. GPS inhibits activation of the EGFR/PI3K/AKT axis by reducing EGFR expression. In vivo experiments indicated that GPS induced significant decrease in tumor volume, and it also inhibited the pulmonary metastasis. For the safety concerns, GPS caused no obvious toxicities to the heart, liver, spleen, lung and kidney tissues. IHC staining confirmed GPS downregulated the activity of EGFR/PI3K/AKT. CONCLUSIONS: Our investigation demonstrated for the first time that GPS could inhibit GC malignant progression by targeting the EGFR/PI3K/AKT signaling pathway. This study indicated that GPS may be serve as a safe anti-tumor drug for further treatment of GC.

A multimodal graph neural network framework for cancer molecular subtype classification.

BACKGROUND: The recent development of high-throughput sequencing has created a large collection of multi-omics data, which enables researchers to better investigate cancer molecular profiles and cancer taxonomy based on molecular subtypes. Integrating multi-omics data has been proven to be effective for building more precise classification models. Most current multi-omics integrative models use either an early fusion in the form of concatenation or late fusion with a separate feature extractor for each omic, which are mainly based on deep neural networks. Due to the nature of biological systems, graphs are a better structural representation of bio-medical data. Although few graph neural network (GNN) based multi-omics integrative methods have been proposed, they suffer from three common disadvantages. One is most of them use only one type of connection, either inter-omics or intra-omic connection; second, they only consider one kind of GNN layer, either graph convolution network (GCN) or graph attention network (GAT); and third, most of these methods have not been tested on a more complex classification task, such as cancer molecular subtypes. RESULTS: In this study, we propose a novel end-to-end multi-omics GNN framework for accurate and robust cancer subtype classification. The proposed model utilizes multi-omics data in the form of heterogeneous multi-layer graphs, which combine both inter-omics and intra-omic connections from established biological knowledge. The proposed model incorporates learned graph features and global genome features for accurate classification. We tested the proposed model on the Cancer Genome Atlas (TCGA) Pan-cancer dataset and TCGA breast invasive carcinoma (BRCA) dataset for molecular subtype and cancer subtype classification, respectively. The proposed model shows superior performance compared to four current state-of-the-art baseline models in terms of accuracy, F1 score, precision, and recall. The comparative analysis of GAT-based models and GCN-based models reveals that GAT-based models are preferred for smaller graphs with less information and GCN-based models are preferred for larger graphs with extra information.

Effects of Different Heterogeneous Nutrient Environments on the Growth and Activities of Enzymes in the Roots of Fokienia hodginsii Families.

Currently, research on the F. hodginsii asexual lineage primarily focuses on the screening of growth traits and the control of single fertilizer applications. The effects of the heterogeneity of soil nutrients on root growth and activity have not been studied in detail. Therefore, we propose forest management measures to improve the foraging ability of forest trees in conjunction with stand productivity. In this experiment, annual containerized seedlings of 10 free-pollinated F. hodginsii lines from a primary asexual seed orchard were used as test subjects, and three heterogeneous nutrient environments of nitrogen (N), phosphorus (P), and potassium (K) were constructed. In contrast, homogeneous nutrient environments were used as the control to carry out potting experiments, to study the growth of F. hodginsii lines and the differences in the activities of root enzymes under the three heterogeneous nutrient environments, and to carry out the comprehensive evaluation using the principal component and cluster analysis method. The results were as follows: (1) The seedling height of F. hodginsii family lines under a homogeneous nutrient environment was significantly higher than that of all heterogeneous nutrient environments; the diameter of the ground was the highest under N heterogeneous nutrient environment and significantly higher than that of all the other nutrient environments; the biomass of the root system was the highest under P heterogeneous nutrient environment, which was significantly higher than that of homogeneous nutrient environment and K heterogeneous nutrient environment. The catalase (CAT) activity of F. hodginsii roots was higher than that of homogeneous nutrients in all heterogeneous nutrient environments but not significant, and the superoxide dismutase (SOD) activity was slightly higher than that of K heterogeneous and homogeneous nutrient environments in N and P heterogeneous nutrient environments. SOD activity was slightly higher than that of K heterogeneous and homogeneous nutrient environments under N, and P. peroxidase (POD) activity in the F. hodginsii root system was the highest under the P heterogeneous nutrient environment, which was significantly higher than that of the other nutrient environments. Unlike the activities of the enzymes, the content of malondialdehyde (MDA) in the roots of F. hodginsii was higher in the heterogeneous environment than in all the other nutrient environments. (2) Under N and P heterogeneous nutrient environments, lines 552 and 590 had higher seedling height, ground diameter, and root enzyme activity, while root biomass was highest in line 544; and under K heterogeneous nutrient environments, line 591 had higher seedling height, ground diameter, and root enzyme activity while root biomass was highest in line 551. In contrast to the patterns of seedling height, accumulation of root biomass and activities of root enzymes, family No. 590 had the highest ground diameter of all the F. hodginsii families under the heterogeneous nutrient environments. Family No. 547 had the highest MDA content. In conclusion, it can be seen that N heterogeneous and homogeneous nutrient environments can significantly increase the seedling height and diameter of F. hodginsii compared with P and K heterogeneous nutrient environments, and N and P heterogeneous nutrient environments can also increase the root biomass, root enzyme activities and significantly reduce the MDA content of F. hodginsii. According to the principal component analysis and cluster analysis, it can be seen that among the 10 F. hodginsii family lines, family lines 590 and 552 have higher evaluation in growth, root biomass accumulation, and enzyme activity.

Sleeve gastrectomy decreased hepatic lipid accumulation by inducing autophagy via AMPK/mTOR pathway.

This study was designed to investigate the roles of autophagy in the attenuation of hepatic lipid accumulation after sleeve gastrectomy (SG). Thirty-two rats were divided into normal control, obesity group, sham group, and SG group. Then serum glucagon-like polypeptide-1 (GLP-1) and lipid accumulation were determined, followed by measuring the activity of autophagy based on immunohistochemistry (IHC) and Western blot analysis. Our data showed significant decrease in the lipid accumulation after SG compared with sham group. GLP-1 and autophagy showed significant increase in rats underwent SG compared with the sham group (P < 0.05). In vitro experiments were conducted to analyze the roles of GLP-1 in autophagy. We knock-downed the expression of Beclin-1 in HepG2, and then analyzed the expression of autophagy-related protein (i.e. LC3BII and LC3BI) and lipid droplet accumulation. In HepG2 cells, GLP-1 analog reduced lipid accumulation by activating autophagy through modulating the AMPK/mTOR signaling pathway. All these concluded that SG decreased hepatic lipid accumulation by inducing autophagy through modulating AMPK/mTOR pathway.

Mesenchymal stem cells elicits Anti-PD1 immunotherapy by targeted delivery of CX3CL1.

Anti-PD1/PDL1 monotherapy has failed to acquire sufficiently ideal results in most solid tumors. Mesenchymal stem cells (MSCs) have been reported to exert therapeutic effects on some tumors, but the functions of MSCs in colorectal cancer (CRC) need further research. In this study, we aimed to investigate the therapeutic effect and the improvement of sensitivity of MSCs to anti-PD1 antibodies (αPD1) in CRC and to evaluate the possible mechanism. The relative distribution of immune cells in tumor microenvironment was examined after the mice were treated with MSC and/or αPD1. Our study revealed that MSC recruits CX3CR1high macrophages and promotes M1 polarization to inhibit tumor growth via highly secretion of CX3CL1.The combination of MSC and αPD1 was superior to monotherapy against CRC. MSC inhibits PD1 expression on CD8+ T cells by facilitating M1 macrophage polarization, which promotes the proliferation of CD8+ T cells, thus improving the sensitivity to αPD1 therapy in CRC. Additionally, the above therapeutic effect disappeared after inhibiting the secretion of CX3CL1 in MSC. Our MSC-based immunotherapeutic strategy simultaneously recruited and activated immune effector cells at the tumor site, suggesting that the combination of MSC and αPD1 could be a potential therapy for CRC.

Analysis of regional vegetable circulation efficiency and its spatial effect considering carbon emission.

In order to explore the evolution process of regional vegetable circulation efficiency and its influencing factors, this paper uses Super-SBM model considering unexpected output and GML index to calculate the vegetable circulation efficiency of 13 provinces (cities) in Central China and its surrounding areas from 2015 to 2019, then conducts spatial autocorrelation analysis on the vegetable circulation efficiency in this region through Moran index. Finally, SPDM model is constructed to explore the spatial effect of the influencing factors on the vegetable circulation efficiency in this region. The results show that (1) the vegetable circulation efficiency of most provinces (cities) in this region is low. (2) The Global Moran's I of the vegetable circulation efficiency in this region is positive, that is, the vegetable circulation efficiency in this region shows a certain degree of spatial agglomeration effect. (3) The level of scientific and technological innovation and the degree of government support have significant positive direct and indirect effects on the efficiency of vegetable circulation in the region, the quality of workers has significant positive indirect effects, and the level of economic development and industrial structure have significant negative indirect effects.

Response of the root morphological structure of Fokienia hodginsii seedlings to competition from neighboring plants in a heterogeneous nutrient environment.

Introduction: Critical changes often occur in Fokienia hodginsii seedlings during the process of growth owing to differences in the surrounding environment. The most common differences are heterogeneous nutrient environments and competition from neighboring plants. Methods: In this study, we selected one-year-old, high-quality Fokienia hodginsii seedlings as experimental materials. Three planting patterns were established to simulate different competitive treatments, and seedlings were also exposed to three heterogeneous nutrient environments and a homogeneous nutrient environment (control) to determine their effect on the root morphology and structure of F. hodginsii seedlings. Results: Heterogeneous nutrient environments, compared with a homogeneous environment, significantly increased the dry matter accumulation and root morphology indexes of the root system of F. hodginsii, which proliferated in nutrient-rich patches, and the P heterogeneous environment had the most significant enhancement effect, with dry matter accumulation 70.2%, 7.0%, and 27.0% higher than that in homogeneous and N and K heterogeneous environments, respectively. Homogeneous environments significantly increased the specific root length and root area of the root system; the dry matter mass and morphological structure of the root system of F. hodginsii with a heterospecific neighbor were higher than those under conspecific neighbor and single-plant treatments, and the root area of the root system under the conspecific neighbor treatment was higher than that under the heterospecific neighbor treatment, by 20% and 23%, respectively. Moreover, the root system under heterospecific neighbor treatment had high sensitivity; the heterogeneous nutrient environment increased the mean diameter of the fine roots of the seedlings of F. hodginsii and the diameter of the vascular bundle, and the effect was most significant in the P heterogeneous environment, exceeding that in the N and K heterogeneous environments. The effect was most significant in the P heterogeneous environment, which increased fine root diameter by 20.5% and 10.3%, respectively, compared with the homogeneous environment; in contrast, the fine root vascular ratio was highest in the homogeneous environment, and most of the indicators of the fine root anatomical structure in the nutrient-rich patches were of greater values than those in the nutrient-poor patches in the different heterogeneous environments; competition promoted most of the indicators of the fine root anatomical structure of F. hodginsii seedlings. According a principal component analysis (PCA), the N, Pm and K heterogeneous environments with heterospecific neighbors and the P heterogeneous environment with a conspecific neighbor had higher evaluation in the calculation of eigenvalues of the PCA. Discussion: The root dry matter accumulation, root morphology, and anatomical structure of F. hodginsii seedlings in the heterogeneous nutrient environment were more developed than those in the homogeneous nutrient environment. The effect of the P heterogeneous environment was the most significant. The heterospecific neighbor treatment was more conducive to the expansion and development of root morphology of F. hodginsii seedlings than were the conspecific neighbor and single-plant treatments.

Sleeve gastrectomy attenuated diabetes-related cognitive decline in diabetic rats.

Objective: To investigate the effects of sleeve gastrectomy (SG) on diabetes-related cognitive decline (DCD) in rats with diabetic mellitus (DM). Methods and methods: Forty Wistar rats were randomly divided into control (CON) group (n=10), diabetes mellitus (DM) group (n=10), sham operation (SHAM) group (n=10) and SG group (n=10). DM model was established by high-fat diet (HFD) combined with intraperitoneal injection of streptozocin (STZ). Behavioral evaluation was given using Morris water maze test and Y-maze. In addition, PET-CT, TUNEL assay, histological analysis, transmission electron microscopy (TEM), immunohistochemistry (IHC) and Western blot analysis were used to evaluate the alleviating effects and potential mechanisms of SG on DCD in DM rats. Results: Compared with the sham group, SG induced significant improvement in the metabolic indices such as blood glucose and body weight. Besides, it could attenuate the insulin resistance compared with SHAM group. In addition, SG could improve the cognitive function of DM rats, which were featured by significant decrease in the escape latency (P<0.05), and significant increase in the time in target quadrant and platform crossings (P<0.05) compared with the SHAM group. SG induced significant elevation in the spontaneous alternation compared with SHAM group (P<0.05). Moreover, SG could improve the arrangement and biosynthesis of hippocampus neuron. Moreover, SG triggered the inhibition of apoptosis of hippocampus neurons, and Western blot analysis showed SG induced significant increase in the ratios of Bcl-2/Bax and Caspase3/cleaved Caspase 3. TEM demonstrated SG could significantly improve the microstructure of hippocampus neurons compared with the SHAM group. Western blot and IHC confirmed the significant decrease in the phosphorylation of tau at Ser404 and Ser396 sites in the SG group. Furthermore, SG activated the PI3K signaling pathway by elevating the phosphorylation of PI3K and Akt and GSK3ß compared with the SHAM group. Conclusion: SG attenuated the DCD in DM rats, which may be related to the activation of PI3K signaling pathway.

Bariatric surgery for diabetic comorbidities: A focus on hepatic, cardiac and renal fibrosis.

Continuously rising trends in diabetes render this disease spectrum an epidemic proportion worldwide. As the disease progresses, the pathological effects of diabetes may impair the normal function of several vital organs, eventually leading to increase the risk of other diabetic comorbidities with advanced fibrosis such as non-alcoholic fatty liver disease, diabetic cardiomyopathy, and diabetic kidney disease. Currently, lifestyle changes and drug therapies of hypoglycemic and lipid-lowering are effective in improving multi-organ function, but therapeutic efficacy is difficult to maintain due to poor compliance and drug reactions. Bariatric surgery, including sleeve gastrectomy and Roux-en-Y gastric bypass surgery, has shown better results in terms of prognosis for diabetes through long-term follow-up. Moreover, bariatric surgery has significant long-term benefits on the function of the heart, liver, kidneys, and other organs through mechanisms associated with reversal of tissue fibrosis. The aim of this review is to describe the impact of type 2 diabetes mellitus on hepatic, cardiac and renal fibrosis and to summarize the potential mechanisms by which bariatric surgery improves multiple organ function, particularly reversal of fibrosis.

Detection of the Spatio-Temporal Differentiation Patterns and Influencing Factors of Wheat Production in Huang-Huai-Hai Region.

The stability of wheat production is closely related to national food security and agricultural sustainable development, and it has been a major policy concern for China. By analyzing the spatiotemporal factors and causes of wheat production, we can grasp the spatiotemporal distribution law of wheat production to rationally allocate agricultural resources. To this end, this study first conducted a quantitative analysis of the yield differentiation patterns in Huang-Huai-Hai (HHH) wheat based on the 2010-2020 wheat agricultural data, comprehensively using the Theil index and exploratory spatial data analysis. Second, to eliminate the spatial heterogeneity and multicollinearity of the modeling variables, a local model of SCA-GWR combining Spearman correlation analysis (SCA) and geographically weighted regression (GWR) was established. Compared with the traditional global regression model, the superiority and applicability of the SCA-GWR model are proved, and it is a simple and effective new method to detect spatial data nonstationarity. Finally, the factors influencing wheat production in the HHH region were detected based on the SCA-GWR local model, and relevant policy recommendations were put forward. The results show that: (1) The yield difference in different farming areas gradually narrowed, and the wheat production had a significant High-High aggregation trend. The center of gravity for wheat production lies in the southwest of the HHH region. (2) Wheat production still has a strong dependence on irrigation and fertilizer. Effective irrigated areas and temperature are the main driving forces for its production. The inhibitory effect of the proportion of nonagricultural employment on wheat production gradually weakened. Radiation and rainfall were only significantly positively correlated with wheat production in the central and southern HHH region. In response to the findings of the study, corresponding policy recommendations are made in terms of optimizing the allocation of resources, increasing investment in agricultural infrastructure, and vigorously researching and developing agricultural science and technology, and the results of the study can provide a basis for decision-making and management by relevant departments.

Etched-And-Regrown GaN P-N Diodes with Low-Defect Interfaces Prepared by In Situ TBCl Etching.

The ability to form pristine interfaces after etching and regrowth of GaN is a prerequisite for epitaxial selective area doping, which in turn is needed for the formation of lateral PN junctions and advanced device architectures. In this work, we report the electrical properties of etched-and-regrown GaN PN diodes using an in situ Cl-based precursor, tertiary butylchloride (TBCl). We demonstrated a regrowth diode with I-V characteristics approaching that from a continuously grown reference diode. The sources of unintentional contamination from the silicon (Si) impurity and the mediating effect of Si during the TBCl etching are also investigated in this study. This work points to the potential of in situ TBCl etching toward the realization of GaN lateral PN junctions.

RGB Arrays for Micro-Light-Emitting Diode Applications Using Nanoporous GaN Embedded with Quantum Dots.

The multiple light scattering of nanoporous (NP) GaN was systematically studied and applied to the color down-conversion for micro-light-emitting diode (LED) display applications. The transport mean free path (TMFP) in NP GaN is 660 nm at 450 nm (light wavelength), and it decreases with a decreasing wavelength. It was observed that the short TMFP of the NP GaN increased the light extinction coefficient at 370 nm by 11 times. Colloidal QDs were loaded into a half 4″ wafer scale NP GaN, and 96 and 100% of light conversion efficiencies for green and red were achieved, respectively. By loading green and red QDs selectively into NP GaN mesas, we demonstrated the RGB microarrays based on the blue-violet pumping light with green and red color converting regions.

The effects of benzo[a]pyrene on the composition of gut microbiota and the gut health of the juvenile sea cucumber Apostichopus japonicus Selenka.

The gut microbiota is essential for health and physiological functions in the host organism. However, the toxicological evaluation of environmental pollutants on the gut microbiota is still insufficient. In the present study, the juvenile sea cucumber Apostichopus japonicus was exposed for 14 days to Benzo[a]pyrene (BaP), which is a model polycyclic aromatic hydrocarbon (PAH), at four different concentrations (0, 0.5, 5, and 25 µg/L). We analyzed the intestinal microbial community of A. japonicas using 16S rRNA gene amplicon sequencing. Our results demonstrate that BaP exposure caused alterations to the microbiome community composition in sea cucumbers. At the phylum level, Planctomycetes were significantly more abundant in BaP exposure groups at 14 d compared with the control group, and the abundance of Proteobacteria and Bacteroidetes increased while the abundance of Firmicutes decreased following BaP exposure. At the genus level, multiple beneficial and autochthonous genera declined in the BaP treatment groups compared to the control, including Lactococcus, Bacillus, Lactobacillus, Enterococcus, Leuconostoc and Weissella; however, a bloom of alkane-degrading bacteria was found in BaP-exposed guts and included Lutibacter, Pseudoalteromonas, Polaribacter, Rhodopirellula and Blastopirellula. Furthermore, histological morphology, enzymatic activity and gene expression analysis revealed that BaP exposure also negatively impacted gut structure and function and presented as inflammation or atrophy, oxidative stress and immune suppression in sea cucumber intestines. Collectively, these findings provide insights into the toxic effects of BaP exposure on A. japonicas associated with intestinal microbiota and health.

The influence of three antibiotics on the growth, intestinal enzyme activities, and immune response of the juvenile sea cucumber Apostichopus japonicus selenka.

The global abuse and misuse of antibiotics in the treatment and prevention of bacterial infections has resulted in the ubiquitous existence of these drugs in aquatic environments, which causes frequent antimicrobial resistance and pollution in ecosystems. However, the chronic effects of antimicrobial agents on aquatic animal growth and health have not been fully evaluated. In the present study, three typical antibiotics (tetracycline, erythromycin, and norfloxacin) were administered orally to juvenile sea cucumbers Apostichopus japonicus for 45 days, to mimic the long-term use of antibiotics. As a result, tetracycline and erythromycin promoted the growth and digestive activity of lipase, pepsin, and trypsin, but norfloxacin did not show significant prompting effect on digestive activity and even retarded the weight gain of the sea cucumbers. The mortality was higher in antibiotic treated groups between the 2nd and 4th days after challenge with Vibrio splendidus. At the same time, lower immune-related parameters were found in antibiotic feeding juveniles, suggesting that the use of antibiotics might weaken the immune defense system of sea cucumbers. This study revealed that antibiotic administration could facilitate the growth of sea cucumbers to varying degrees yet coupled with high risks of impaired immune function and compromised disease resistance.

MicroRNA MIMIC binding sites: Minor flanking nucleotide alterations can strongly impact MIMIC silencing efficacy in Arabidopsis.

In plants, microRNA (miRNA) target MIMICs (MIMs) have been widely used to inhibit miRNA function. They are based on the Arabidopsis INSENSITIVE TO PHOSPATE STARVATION 1 (IPS1) gene that corresponds to a non-coding RNA containing a miR399 binding site that can be modified to sequester and inhibit any miRNA of interest. However, the efficacy of miRNA inhibition of these different MIMs can vary greatly. Using MIMs that have strong efficacy (MIM159) and poor efficacy (MIM165), we investigate the underlying cause of this variation. Firstly, sequence alignments of IPS1 homologs from the Brassicaceae identified a highly conserved sequence immediately downstream of the miRNA binding site. Mutating this sequence in the context of the MIM159 attenuates its strong efficacy. This conserved flanking region contains a predicted stem-loop structure that is also predicted to be present in most modified MIMs that appear to have a strong efficacy, but not in MIM165 that has a poor efficacy. Restoring this predicted stem-loop in MIM165 via mutation of only three or five nucleotides within the conserved flanking region resulted in MIM165 variants that have very strong efficacies of miRNA inhibition. However, specifically mutating this predicted stem-loop in the MIM159 context failed to significantly reduce efficacy, and additional mutations to restore this predicted stem-loop weakened efficacy further. Although this shows there is no simple correlation between this predicted stem-loop and efficacy, these results add to the growing evidence that the sequence context of miRNA binding sites is important, and that minor nucleotide substitutions to flanking sequences of miRNA binding sites can strongly enhance or attenuate the miRNA-target interaction.