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1.
J Hazard Mater ; 423(Pt B): 127048, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34537642

RESUMO

Bifunctional oxygen-doped graphitic carbon nitride (OCN) was fabricated to activate peroxymonosulfate (PMS) for degrading imidacloprid (IMD). The modulated electronic structure of OCN promoted the adsorption, electron transfer, and formation of the redox site of PMS. The light absorption capacity, and the separation and migration speed of photogenerated carriers of OCN were increased. Consequently, 94.5% of IMD (3.0 mg/L) was removed by OCN-10/PMS process in 2.0 h. Compared with g-C3N4/PMS (0.048 h-1), the IMD degradation rate constant of OCN-10/Vis/PMS system (1.501 h-1) was increased by 30.3 times. The PMS oxidation on electron-deficient C atoms and holes, the PMS reduction around electron-rich O atoms and photogenerated electrons, and the multiple reactions of superoxide radical were the sources of the main active species singlet oxygen. Moreover, even under different pH conditions, coexisting anions, humic acid, and other neonicotinoid pesticides, the OCN-10/Vis/PMS system still showed acceptable applicability. Finally, mass spectrometry identified that hydroxylation and N-dealkylation of amines were the primary degradation pathways of IMD. This paper demonstrates an environmental-friendly combined activation strategy of PMS that can be operated day and night with low energy consumption, aiming to pave the way for developing metal-free photocatalysts for high-efficient environmental purification based on advanced oxidation coupling technology.

2.
Sci Rep ; 11(1): 23115, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848784

RESUMO

To compare stent-induced granulation tissue hyperplasia of bare (SEMS), polyurethane-covered (PU-SEMS) and electrospun nanofibre-covered (EN-SEMS) self-expandable metallic stents in the rabbit trachea. Twenty-seven rabbits were randomly assigned to 3 groups that received SEMS, PU-SEMS or EN-SEMS. Computed tomography and sacrifice were performed as scheduled. Haematoxylin-eosin and Masson's trichrome staining protocols were performed for pathological analysis. The data for tracheal ventilation area ratio, qualitative histological scoring, number of epithelial layers, and thicknesses of papillary projection and submucosa were documented and statistically analysed. All stents were successfully placed under the guidance of fluoroscopy without complications. Post-stenting 3 and 7 days, computed tomography revealed that the fully expandable EN-SEMS was similar to the SEMS and PU-SEMS. The mean stented tissue score in the SEMS group was higher than those of both the PU-SEMS and EN-SEMS groups at 3 days post-stenting. The pathological findings suggested that there was no papillary projection formation 3 days after stent placement. The thickness of papillary projection in the SEMS group was significantly higher than those of the PU-SEMS and EN-SEMS groups at 7 days post-stenting. After stenting 4 weeks, the tracheal ventilation area ratio of SEMS, PU-SEMS and EN-SEMS was 0.214 ± 0.021, 0.453 ± 0.028 and 0.619 ± 0.033, respectively. There were significant between-group differences. In conclusion, the stent-induced granulation tissue formation in EN-SEMS is less severe than that of PU-SEMS and SEMS. EN-SEMS has smaller radial force, and the tracheal ventilation ratio after stent placement better than that of PU-SEMS.

3.
Wei Sheng Yan Jiu ; 50(5): 775-780, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34749871

RESUMO

OBJECTIVE: Used low density lipoprotein receptor knockout(LDLR KO) hamster as the model similar to human dyslipidemia to observe the lipid-lowering effect of equol on heterozygotes. METHODS: With soy-free high cholesterol high fat diet, 12-week-old LDLR KO female heterozygous hamsters were randomly divided into negative control group(no addition), positive control group(add 0.004% ezetimibe), genistein group(add 0.1%), and low, medium and high-dose groups of equol(add 0.025%, 0.05%, 0.1% respectively). Body weight, food consumption and blood lipid were continuously monitored for 12 weeks after feeding each group. Finally, liver morphology and lipid metabolism related genes expressions were checked. RESULTS: There was no significant difference in body weight and average weekly food intake among the groups. The blood lipids in negative control group increased over time, and the cholesterol and triglyceride levels of LDLR KO heterozygous hamsters were significantly reduced by ezetimibe in the second week, while the high-density lipoprotein cholesterol was also significantly decreased. The lipid-lowering effects of genistein and equol were weaker than ezetimibe, and there was significant difference between the two groups after 12 weeks, but the decrease of HDL-c was not as significant as ezetimibe. Compared with genistein, the effect of medium and high dose equol was stronger. At 12 weeks, the liver weight ratio also decreased significantly, and the liver lipid accumulation was inhibited, especially in the high dose of equol. The expression of ApoAI, SREBP-2 and HMGCR were significantly up-regulated by equol and genistein. CONCLUSION: Equol could reduce female LDLR KO hamster blood lipid. It may play a role in lipid lowering by inhibiting cholesterol absorption besides estrogen receptor pathway, but it is weaker than NPC1 L1 inhibitor. At the same time, up-regulation of ApoAI inhibits the decrease of high-density lipoprotein and reduces lipid accumulation in liver.


Assuntos
Equol , Receptores de LDL , Animais , Colesterol , HDL-Colesterol , Cricetinae , Feminino , Humanos , Lipídeos , Fígado , Receptores de LDL/genética
4.
Front Cardiovasc Med ; 8: 738060, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796210

RESUMO

Elevated triglycerides are associated with an increased risk of cardiovascular disease (CVD). Therefore, it is very important to understand the metabolism of triglyceride-rich lipoproteins (TRLs) and their atherogenic role in animal models. Using low-density lipoprotein receptor knockout (LDLR-/-) Syrian golden hamsters, this study showed that unlike LDLR-/- mice, when LDLR-/- hamsters were fed a high cholesterol high-fat diet (HFD), they had very high plasma levels of triglycerides and cholesterol. We found that LDLR-/- hamsters exhibited increased serum TRLs and the ApoB100 and 48 in these particles after being fed with HFD. Treatment with ezetimibe for 2 weeks decreased these large particles but not the LDL. In addition, ezetimibe simultaneously reduced ApoB48 and ApoE in plasma and TRLs. The expression of LRP1 did not change in the liver. These findings suggested that the significantly reduced large particles were mainly chylomicron remnants, and further, the remnants were mainly cleared by the LDL receptor in hamsters. After 40 days on an HFD, LDLR-/- hamsters had accelerated aortic atherosclerosis, accompanied by severe fatty liver, and ezetimibe treatment reduced the consequences of hyperlipidemia. Compared with the serum from LDLR-/- hamsters, that from ezetimibe-treated LDLR-/- hamsters decreased the expression of vascular adhesion factors in vascular endothelial cells and lipid uptake by macrophages. Our results suggested that in the LDLR-/- hamster model, intestinally-derived lipoprotein remnants are highly atherogenic and the inflammatory response of the endothelium and foam cells from macrophages triggered atherosclerosis. The LDL receptor might be very important for chylomicrons remnant clearance in the Syrian golden hamster, and this may not be compensated by another pathway. We suggest that the LDLR-/- hamster is a good model for the study of TRLs-related diseases as it mimics more complex hyperlipidemia.

5.
Front Cardiovasc Med ; 8: 734824, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692787

RESUMO

High-density lipoprotein (HDL) homeostasis is important in maintaining both cardiovascular and renal health. Scavenger receptor class B type 1 (SR-B1), the major HDL receptor in mammals, plays a crucial role in reverse cholesterol transport and HDL metabolism. Evidence from mouse study has well demonstrated that HDL disorders caused by Srb1 inactivation accelerate atherosclerosis and even induce lethal cardiovascular diseases. However, the renal consequences of Srb1 dysfunction are still unknown. Here we explored this issue in both Srb1 knockout (Srb1-/-) mice and atherosclerotic low-density lipoprotein receptor knockout (Ldlr-/-) mice with Srb1 deletion. Our data showed that no apparent renal damage was observed in 5-month-old Srb1-/- mice fed on standard rodent chow diet as well as Srb1-/- mice fed on a high-fat diet (HFD) for 12 weeks. However, 5-month-old Srb1/Ldlr-/- mice fed on rodent chow had increased urinary albumin excretion and developed spontaneous intraglomerular Oil-red O (ORO)-positive lipoprotein deposition that is similar to lesions observed in human lipoprotein glomerulopathy (LPG). HFD feeding accelerated LPG-like lesions in Srb1/Ldlr-/- mice, inducing severe proteinuria and significantly promoting intraglomerular ORO-positive lipoprotein deposition. Interestingly, probucol reversed HFD-induced HDL disorders and almost fully abrogated LPG-like lesions in Srb1/Ldlr-/- mice. In conclusion, the present study demonstrates that SR-B1 dysfunction leads to LPG-like lesions in atherosclerotic mice, which could be rescued by probucol. SR-B1 loss-of-function mutant carriers therefore might be susceptible to developing metabolic nephropathy in addition to cardiovascular diseases, and probucol might be a potential therapeutics.

6.
Sci Total Environ ; : 151025, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662606

RESUMO

Dewatering treatment is an essential step to diminish sludge volume, cut down transportation costs, and improve subsequent disposal efficiency. In this study, ozone-peroxymonosulfate (O3/PMS) oxidation process was employed to ameliorate sludge dewaterability. Sludge capillary suction time (CST) and water content (Wc) of dewatered sludge cake could reduce from 70.5 s and 81.93% to 26.7 s and 65.65%, respectively, under the optimal dosage of 30 mg/g TS O3 and 0.4 mmol/g TS PMS. The increased sludge zeta potential, particle size, and fluidity promoted sludge dewatering performance apparently. The decreased hydrophilic, fluorescent EPS components and proteins/peptides-like + Lipids percentage in EPS as well as the ratio of α-helix/(ß-sheet + random coil) of treated EPS protein secondary structure was greatly responsible for the enhanced sludge dewaterability. SO4- and OH were detected in ozone-peroxymonosulfate process to crack sludge flocs, eliminate hydrophilic substances and liberate bound water. Moreover, the concentrations of both heavy metals and polycyclic aromatic hydrocarbons (PAHs) of sludge after O3/PMS conditioning were decreased, and the stability and toxicity of heavy metals were also reduced, except Zn. In conclusion, this work offered a comprehensive insight based on ozone-peroxymonosulfate (O3/PMS) advanced oxidation for improving the sludge dewaterability and environmental implication.

7.
Shanghai Kou Qiang Yi Xue ; 30(4): 389-393, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34693432

RESUMO

PURPOSE: This study investigated the effectiveness of orofacial myofunctional therapy(OMT) in improving facial morphology of children with obstructive sleep apnea (OSA) after adenotonsillectomy (AT). METHODS: Ten children aged from 4-7 years with persistent oral breathing for more than 1 month after adenotonsillectomy were chosen to receive orofacial myofunctional therapy. The patients were required to take photos before and after orofacial myofunctional therapy. In order to compare the soft changes before and after OMT treatment, twelve representative mark points were selected and used for proportion and angle measurements. Graphpad Prism 8 statistical software was used for statistical analysis, to compare the differences in facial morphology of patients before and after treatment. RESULTS: Compared with before OMT, a significant difference was found in the proportion of Sn-Ls/Sn-Stms(P=0.0002), Sn-Stms/Sn-Me'(P<0.05), as well as in the angle of Gs-Sn-Pos (P<0.05), nasolabial angle(P=0.0005), mentolabial angle (P=0.0026) after OMT treatment. CONCLUSIONS: Orofacial myofunctional therapy can be considered as an effective complementary treatment for OSA patients with oral breathing after adenotonsillectomy.


Assuntos
Apneia Obstrutiva do Sono , Tonsilectomia , Adenoidectomia , Criança , Face , Humanos , Terapia Miofuncional , Apneia Obstrutiva do Sono/terapia
8.
mSystems ; 6(5): e0080721, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34491088

RESUMO

Nitrogen in different chemical forms is critical for metabolic alterations in Monascus strains and associated pigment diversity. In this study, we observed that ammonium-form nitrogen was superior in promoting the biosynthesis of Monascus pigments (MPs) when compared with nitrate and organic forms. Moreover, with any nitrogen source, the production of yellow and orange pigments was highly synchronized but distantly related to red pigments. However, transcriptional analyses of MP gene clusters suggested a low contribution to MP accumulation, suggesting that MP-limiting factors were located outside the gene cluster. Our metabolomic analyses demonstrated that red pigment biosynthesis was closely related to intracellular amino acids, whereas orange and yellow pigments were associated with nucleotides. In addition, weighted gene coexpression network analyses (WGCNA) based on transcriptomic data showed that multiple primary metabolic pathways were closely related to red pigment production, while several secondary pathways were related to orange pigments, and others were involved with yellow pigment regulation. These findings demonstrate that pigment diversity in Monascus is under combined regulation at metabolomic and transcriptomic levels. IMPORTANCE Natural MPs containing a mixture of red, orange, and yellow pigments are widely used as food coloring agents. MP diversity provides foods with versatile colors and health benefits but, in turn, complicate efforts to achieve maximum yield or desirable combination of pigments during the manufacturing process. Apart from the MP biosynthetic gene cluster, interactions between the main biosynthetic pathways and other intracellular genes/metabolites are critical to our understanding of MP differentiation. The integrative multiomics analytical strategy provides a technical platform and new perspectives for the identification of metabolic shunting mechanisms in MP biosynthesis. Equally, our research highlights the influence of intracellular metabolic alterations on MP differentiation, which will facilitate the rational engineering and optimization of MP production in the future.

9.
Am J Transl Res ; 13(8): 9578-9585, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540081

RESUMO

OBJECTIVE: This study explored and analyzed the effects of butylphthalide injection on the cognitive function and on the TLRs/NF-κB pathway in hypertensive intracerebral hemorrhage patients. METHODS: A total of 115 patients admitted to our hospital with hypertensive intracerebral hemorrhages were recruited as the study cohort and randomly placed in the observation group (n=60) or the control group (n=55). In addition to the routine treatment administered in both groups, the control group was additionally administered oral nimodipine tablets, and the observation group was administered intravenous butylphthalide injections. Both groups were treated continuously for 14 days. Subsequently, the changes in the clinical efficacy, the NIHSS scores, the extremity motor function, the Fugl-Meyer scores, the blood-brain barrier (BBB) and the peripheral blood mononuclear cells (PBMCs), the TLR2, TLR9, and the NF-κB mRNA levels in the two groups before and after the treatment were compared, and any adverse reactions were observed. RESULTS: The total effective rate in the observation group was significantly superior to the total effective rate in the control group (P<0.05). The post-treatment NIHSS scores in the two groups were dramatically lower (P<0.05), and the post-treatment scores in the observation group were significantly lower than they were in the control group (P<0.05). The post-treatment cerebral spinal fluid (CSF) albumin and BBB indexes in the two groups were decreased significantly compared to their pre-treatment levels (P<0.05), and the post-treatment indexes in the observation group were significantly lower than the post-treatment indexes in the control group (P<0.05). The post-treatment relative TLR2, TLR9, and NF-κB mRNA expressions in the two groups were apparently lower than their in pre-treatment levels (P<0.05), and the relative expressions in the observation group after the treatment were clearly lower than they were in the control group (P<0.05). CONCLUSION: Butylphthalide injection has a high clinical efficacy in treating hypertensive intracerebral hemorrhages. The drug can effectively improve patients' cognitive functions, extremity motor functions, and BBB indexes, and its mechanism may connect with the expressive suppression of the TLRs/NF-κB signaling pathway. The treatment is safe and effective, so it is worthy of clinical promotion.

10.
Org Lett ; 23(19): 7336-7341, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523943

RESUMO

Exploration of the diastereodivergent synthesis of spirocyclic oxindoles has been challenging. Herein we report asymmetric [3 + 2] annulations of isatin-derived Morita-Baylis-Hillman (MBH) carbonates and 5-alkenylthiazol-4(5H)-ones. Interestingly, two different chiral catalysts, amide-phosphine and 4-dimethylaminopyridine (DMAP)-thiourea, could lead to two kinds of diastereomeric dispiro oxindoles with three contiguous stereogenic centers. The hexafluoroisopropanol (HFIP) additive plays a vital role in accelerating the reaction and tuning the diastereoselectivity. Moreover, both annulation adducts could be further converted to structurally diverse spirooxindoles.

11.
J Nanobiotechnology ; 19(1): 260, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34454524

RESUMO

BACKGROUND: Fluorescent carbon-dots (CDs) with multifaceted advantages have provided hope for improvement of crop growth. Near infrared (NIR) CDs would be more competitive and promising than short-wavelength emissive CDs, which are not directly utilized by chloroplast. The molecular targets and underlying mechanism of these stimulative effects are rarely mentioned. RESULTS: NIR-CDs with good mono-dispersity and hydrophily were easily prepared by a one-step microwave-assisted carbonization manner, which showed obvious UV absorptive and far-red emissive properties. The chloroplast-CDs complexes could accelerate the electron transfer from photosystem II (PS II) to photosystem I (PS I). NIR-CDs exhibited a concentration-dependent promotion effect on N. benthamiana growth by strengthening photosynthesis. We firstly demonstrated that potential mechanisms behind the photosynthesis-stimulating activity might be related to up-regulated expression of the photosynthesis and chloroplast synthesis related genes, among which PsbP and PsiK genes are the key regulators. CONCLUSION: These results illustrated that NIR-CDs showed great potential in the applications to increase crop yields through ultraviolet light harvesting and elevated photosynthesis efficiency. This work would provide a theoretical basis for the understanding and applications of the luminescent nanomaterials (not limited to CDs) in the sunlight conversion-related sustainable agriculture.

12.
Syst Appl Microbiol ; 44(5): 126234, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34343788

RESUMO

Rpf protein, a kind of resuscitation promoting factor, was first found in the culture supernatant of Micrococcus luteus. It can resuscitate the growth of M. luteus in "viable but non-culture, VBNC" state and promote the growth of Gram-positive bacteria with high G + C content. This paper investigates the resuscitating activity of M. luteus ACCC 41016T Rpf protein, which was heterologously expressed in E. coli, to cells of M. luteus ACCC 41016T and Rhodococcus marinonascens HBUM200062 in VBNC state, and examines the effect on the cultivation of actinobacteria in soil. The results showed that the recombinant Rpf protein had resuscitation effect on M. luteus ACCC 41016T and R. marinonascens HBUM200062 in VBNC state. 83 strains of actinobacteria, which were distributed in 9 families and 12 genera, were isolated from the experimental group with recombinant Rpf protein in the culture medium. A total of 41 strains of bacteria, which were distributed in 8 families and 9 genera, were isolated from the control group without Rpf protein. The experimental group showed richer species diversity than the control group. Two rare actinobacteria, namely HBUM206391T and HBUM206404T, were obtained in the experimental group supplemented with Rpf protein. Both may be potential new species of Actinomadura and Actinokineospora, indicating that the recombinant expression of M. luteus ACCC 41016T Rpf protein can effectively promote the isolation and culture of actinobacteria in soil.


Assuntos
Actinobacteria , Proteínas de Bactérias/metabolismo , Citocinas/metabolismo , Micrococcus luteus/metabolismo , Microbiologia do Solo , Actinobacteria/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Citocinas/genética , Escherichia coli , Rhodococcus
13.
Front Immunol ; 12: 708678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381457

RESUMO

Innate lymphoid cells (ILCs) are emerging as important players in inflammatory diseases. The oral mucosal barrier harbors all ILC subsets, but how these cells regulate the immune responses in periodontal ligament tissue during periodontitis remains undefined. Here, we show that total ILCs are markedly increased in periodontal ligament of periodontitis patients compared with healthy controls. Among them, ILC1s and ILC3s, particularly NKp44+ILC3 subset, are the predominant subsets accumulated in the periodontal ligament. Remarkably, ILC1s and ILC3s from periodontitis patients produce more IL-17A and IFN-γ than that from healthy controls. Collectively, our results highlight the role of ILCs in regulating oral immunity and periodontal ligament inflammation and provide insights into targeting ILCs for the treatment of periodontitis.

14.
Int Immunopharmacol ; 99: 107901, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273637

RESUMO

Periodontitis is initiated by serious and sustained bacterial infection and ultimately results in chronic immune-mediated inflammation, tissue destruction, and bone loss. The pathogenesis of periodontitis remains unclear. Host immunological responses to periodontal bacteria ultimately determine the severity and mechanisms governing periodontitis progression. This study aimed to clarify the effect of the hypoxia-inducible factor-1α (HIF-1α) activator dimethyloxalylglycine (DMOG) on a mouse periodontitis model and its underlying role in macrophage polarization. qRT-PCR analysis showed that DMOG inhibited the M1-like polarization of both RAW264.7 macrophages and murine bone marrow macrophages (BMMs) and downregulated TNF-α, IL-6, CD86, and MCP-1 expression in vitro. Immunofluorescence staining and flow cytometry also confirmed the less percentage of F4/80 + CD86 + cells after DMOG treatment. The phosphorylation of NF-κB pathway was also inhibited by DMOG with higher level of HIF-1α expression. Furthermore, mice treated with DMOG showed decreased alveolar bone resorption in the experimental periodontitis model, with significant increases in alveolar bone volume/tissue volume (BV/TV) and bone mineral density (BMD). DMOG treatment of mice decreased the ratio of M1/M2 (CD86+/CD206+) macrophages in periodontal tissues, resulting in the downregulation of proinflammatory cytokines such as TNF-α and IL-6 and increased levels of anti-inflammatory factors such as IL-4 and IL-10. DMOG treatment promoted the number of HIF-1α-positive cells in periodontal tissues. This study demonstrated the cell-specific roles of DMOG in macrophage polarization in vitro and provided insight into the mechanism underlying the protective effect of DMOG in a model of periodontitis.

15.
Transl Oncol ; 14(10): 101179, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34284202

RESUMO

Gain-of-function Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations occur in 25% of lung adenocarcinomas, and these tumors are challenging to treat. Some preclinical work, largely based on cell lines, suggested KRASmut lung cancers are especially dependent on the nuclear export protein exportin-1 (XPO1), while other work supports XPO1 being a broader cancer dependency. To investigate the sensitivity of KRASmut lung cancers to XPO1 inhibition in models that more closely match clinical tumors, we treated 10 independently established lung cancer patient-derived tumor xenografts (PDXs) with the clinical XPO1 inhibitor, Selinexor. Monotherapy with Selinexor reduced tumor growth in all KRASmut PDXs, which included 4 different codon mutations, and was more effective than the clinical MEK1/2 inhibitor, Trametinib. Selinexor was equally effective in KRASG12C and KRASG12D tumors, with TP53 mutations being a biomarker for a weaker drug response. By mining genome-wide dropout datasets, we identified XPO1 as a universal cancer cell dependency and confirmed this functionally in two KRASWT PDX models harboring kinase drivers. However, targeted kinase inhibitors were more effective than Selinexor in these models. Our findings support continued investigation of XPO1 inhibitors in KRASmut lung adenocarcinoma, regardless of the codon alteration.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34181556

RESUMO

Learning a stable and generalizable centralized value function (CVF) is a crucial but challenging task in multiagent reinforcement learning (MARL), as it has to deal with the issue that the joint action space increases exponentially with the number of agents in such scenarios. This article proposes an approach, named SMIX(λ), that uses an off-policy training to achieve this by avoiding the greedy assumption commonly made in CVF learning. As importance sampling for such off-policy training is both computationally costly and numerically unstable, we proposed to use the λ-return as a proxy to compute the temporal difference (TD) error. With this new loss function objective, we adopt a modified QMIX network structure as the base to train our model. By further connecting it with the Q(λ) approach from a unified expectation correction viewpoint, we show that the proposed SMIX(λ) is equivalent to Q(λ) and hence shares its convergence properties, while without being suffered from the aforementioned curse of dimensionality problem inherent in MARL. Experiments on the StarCraft Multiagent Challenge (SMAC) benchmark demonstrate that our approach not only outperforms several state-of-the-art MARL methods by a large margin but also can be used as a general tool to improve the overall performance of other centralized training with decentralized execution (CTDE)-type algorithms by enhancing their CVFs.

17.
J Interpers Violence ; : 8862605211028285, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34167374

RESUMO

Despite widely linking cyberbullying victimization (CV) to some poorer mental health outcomes, CV also negatively impacts the internal strengths that make life worth living, such as meaning in life, which has received less attention. This study thus aimed to examine the relationship between CV and presence of meaning in life as well as the mediating roles of fatalism and self-concept clarity in this relationship. Gender differences in the mediation model were also examined. A sample of 766 Chinese junior school students (M = 13.11 years, SD = 1.19 years) completed questionnaires regarding CV, presence of meaning, self-concept clarity, and fatalism. The results revealed that CV was significantly and positively correlated with presence of meaning. Structural equation modeling indicated that self-concept clarity and fatalism completely mediated the link between CV and presence of meaning in parallel and sequential manners. The multigroup analysis further showed that CV was positively related to fatalism only among girls and had a stronger negative association with self-concept clarity for girls compared with boys. Thus, the indirect link between CV and presence of meaning was stronger for girls (versus boys). Findings suggested that CV was associated with poor self-concept clarity, stronger fatalism, and low levels of presence of meaning in life among adolescents, especially for girls. Increasing self-concept clarity and decreasing fatalistic beliefs are thus necessary to help cyberbullying victims to develop meaning in life.

18.
Environ Pollut ; 287: 117616, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34174663

RESUMO

The co-occurrence of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in agricultural soils has become a worldwide food crop security concern. Pot experiments, rhizosphere microbial metagenomic sequencing, and root metatranscriptomic sequencing were performed to investigate the interactions among pyrene, Cu, and Cd in a soil-maize (Zea mays L.) system. This study provided direct evidence that the co-presence of PAHs and heavy metals changed the root physiological functions and the rhizosphere microbial community, which subsequently influenced the fate of the contaminants. Co-contamination at low levels tended to enhance the uptake potential and biodegradation performance of the plant, whereas increased contaminant concentrations produced opposite effects. The co-presence of 1000 mg/kg Cu decreased the abundance of Mycobacterium in the rhizosphere and reduced pyrene degradation by 12%-16%. The presence of 400-750 mg/kg pyrene altered the metabolic processes, molecular binding functions, and catalytic activity of enzymes in the maize roots, thus impeding the phytoextraction of Cu and Cd. Competitive absorption between Cu and Cd was observed for the 800-1000 mg/kg Cu and 50-100 mg/kg Cd co-treatment, in which Cu showed a competitive advantage, enhancing its root-to-shoot translocation. These findings provide important information for the production of safe crops and for the development of phytoremediation technologies.


Assuntos
Metais Pesados , Microbiota , Poluentes do Solo , Biodegradação Ambiental , Metais Pesados/análise , Raízes de Plantas/química , Pirenos , Rizosfera , Solo , Poluentes do Solo/análise , Zea mays
19.
Sci Rep ; 11(1): 12701, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135411

RESUMO

About 2.6 million third-trimester stillbirths occur annually worldwide, mostly in low- and middle-income countries. However, the causes of stillbirths are rarely investigated. We performed a retrospective, hospital-based study in Zhejiang Province, southern China, of the causes of third-trimester stillbirths. Causes of stillbirths were classified using the Relevant Condition at Death classification system. From January 1, 2013, to December 31, 2018, we enrolled 341 stillbirths (born to 338 women) from 111,275 perinatal fetuses (born to 107,142 women), as well as 293 control cases (born to 291 women). The total incidence of third-trimester stillbirths was 3.06/1000 (341/111,275). There were higher proportions of women with a high body mass index, twins, pregnancy-induced hypertension, assisted reproduction and other risk factors among the antepartum than the control cases. The antepartum stillbirth fetuses were of lower median birth weight and gestational age and had a smaller portion of translucent amniotic fluid than the control cases. The antepartum stillbirth fetuses had a higher frequency of abnormalities detected prenatally and of fetal growth restriction than the control cases. Of 341 cases (born to 338 mothers), the most common causes of stillbirth were fetal conditions [117 (34.3%) cases], umbilical cord [88 (25.8%)], maternal conditions [34 (10.0%)], placental conditions [31 (9.1%)], and intrapartum [28 (8.2%)]. Only eight (2.3%), three (0.9%), and two (0.6%) stillbirths were attributed to amniotic fluid, trauma, and uterus, respectively. In 30 (8.8%) cases, the cause of death was unclassified. In conclusion, targeted investigation can ascertain the causes of most cases of third-trimester stillbirths.


Assuntos
Terceiro Trimestre da Gravidez , Natimorto/epidemiologia , China/epidemiologia , Feminino , Feto , Idade Gestacional , Humanos , Hipertensão Induzida pela Gravidez/epidemiologia , Incidência , Masculino , Doenças Placentárias/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Gravidez de Gêmeos , Estudos Retrospectivos , Fatores de Risco , Cordão Umbilical/patologia
20.
J Interpers Violence ; : 8862605211023486, 2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34092135

RESUMO

Although some studies have explored the psychological and behavioral outcomes of social comparison orientation (SCO), few have explored the associations of SCO with cyberbullying perpetration and victimization. The current study aimed to investigate the associations of SCO with cyberbullying perpetration and victimization, and considered envy on social networking sites (SNS) as a mediator and body satisfaction as a moderator in these relations. To test our expectations, 941 adolescents aged between 10 and 16 years (M = 13.15, SD = 1.18) completed multiple questionnaires, namely the Social Comparison Orientation Scale, the Revised Cyber Bullying Inventory, an envy scale revised for the SNS context, and the Body Areas Satisfaction Scale. Correlation analysis revealed that cyberbullying perpetration and cyberbullying victimization were significantly and positively correlated with SCO and envy on SNS, and significantly and negatively correlated with body satisfaction. The results of structural equation modeling (SEM) revealed that envy on SNS played a mediating role in the associations of SCO with cyberbullying perpetration and victimization. The results of SEM and simple slope test analysis indicated that body satisfaction weakened the direct association of SCO with envy on SNS and further weakened the indirect associations of SCO with cyberbullying perpetration and victimization via envy on SNS. Specifically, individuals with high levels of SCO were more likely to feel envious on SNS, and further tended to bully others and be bullied online when they were dissatisfied with their bodies. In other words, positive body satisfaction protected individuals with high levels of SCO from cyberbullying perpetration and victimization by decreasing their feelings of envy on SNS.

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