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1.
Chem Commun (Camb) ; 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32191783

RESUMO

Herein, a new "Y-series" non-fullerene acceptor, Y21, bearing an asymmetric electron-deficient-core (DA'D) and fluorinated dicyanomethylene derivatives as flanking groups, was designed and synthesized for organic solar cell applications. Rather than being a perfect C2 symmetric traditional "Y-series" acceptor, Y21 possesses an electron-withdrawing unit (A') shifted from the center of DA'D, turning into an asymmetric molecular geometry. Photovoltaic devices based on PM6:Y21 can realize a high Jsc of 24.9 mA cm-2 and a PCE of 15.4%. Our work demonstrates a new way to tune the photoelectronic properties of the "Y-series" NFAs.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32148023

RESUMO

In this work, three benzodithiophene-benzotriazole alternated wide band gap copolymers attaching symmetric or asymmetric conjugated side chains, namely, PDBTFBTA-2T, PBDTFTBA-TSi, and PBDTFBTA-2Si, were developed for efficient nonfullerene polymer solar cells. The symmetry effect of the side chains was investigated in detail on the overall properties of these donor polymers. The results demonstrated that the introduced siloxane functional groups showed less effect on the absorption and frontier orbital levels of the prepared polymers but had a significant effect on the miscibility between these polymer donors and the nonfullerene acceptor. When increasing the content of siloxane functional groups, the miscibility of the polymer donors and Y6 would be improved, leading to the decreased domain size and more mixed domains. Interestingly, the active blend based on PBDTFTBA-TSi with asymmetric side chains exhibited more balanced miscibility, carrier mobility, and phase separation, benefiting exciton diffusion and dissociation. Therefore, a champion power conversion efficiency (PCE) of 14.18% was achieved finally in PBDTFTBA-TSi devices, which was 20.6 and 19.0% higher than the symmetric counterparts of PBTFBTA-2T devices (PCE = 11.76%) and PBDTFBTA-2Si devices (PCE = 11.92%), respectively. This work highlights that the asymmetric side-chain engineering based on siloxane functional groups is a promising design strategy for high-performance polymer donor semiconductors.

3.
Neurobiol Aging ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32204957

RESUMO

With the steadily increasing prevalence of Alzheimer's disease (AD) and great difficulties encountered for AD drug development presently, much interest has been devoted to identifying modifiable risk factors to lower the risk of AD, while the causal associations between risk factors and AD remain inconclusive. The present study conducted a comprehensive evaluation of the causal associations between risk factors and AD development by taking the recent advancements of Mendelian randomization (MR). Inverse variance weighted (IVW), MR-Egger, weighted median, and weighted mode were used for complementary calculation. A total of 45 risk factors and corresponding studies were covered in the study. This two-sample MR (2SMR) analysis provided a suggestive association between genetically predicted higher years of schooling and reduced risks of AD, and each standard deviation (3.71 years) increased in years of schooling was associated with a 41% reduction in the risk of AD (IVW, OR: 0.59, 95% CI: 0.45-0.77). At the same time, it was genetically predicted that urate might be a risk factor in AD, and it was found that each standard deviation increase in urate levels (1.33 mg/dL) was associated with a 0.09-fold increase in the risk of AD (IVW, OR: 1.09, 95% CI: 1.01-1.18). To summarize, the 2SMR analysis indicated a suggestive association between genetically predicted higher years of schooling and reduced risks of AD, and between genetically predicted higher urate levels and increased risks of AD. The findings provide useful clues to help combat AD and warrants future studies.

4.
Cell Biochem Funct ; 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32212193

RESUMO

Deregulated glucose and lipid metabolism are the primary underlying manifestations associated with diabetes mellitus (DM) and non-alcoholic fatty liver disease (NAFLD). This study aims to investigate the role of Gm10804, a novel long non-coding RNA (lncRNA), in regulating hepatic glucose and lipid metabolism in DM complicated with NAFLD (DM-NAFLD). Mouse primary hepatocytes exposed to high glucose (HG) were used as a cell model. A mouse DM-NAFLD model was established by high-energy feeding combined with intraperitoneal injection of streptozotocin. The results showed that Gm10804 expression was upregulated in HG-treated hepatocytes and livers from DM-NAFLD mice. Results in hepatocytes in vitro demonstrated that Gm10804 overexpression aggravated, whereas Gm10804 silencing abrogated HG-induced increase in intracellular triglyceride (TG) content, lipid accumulation and expression of hepatic lipogenic proteins (sterol regulatory element-binding proteins 1-c [SREBP-1c] and fatty acid synthase [FAS]) and enzymes for gluconeogenesis (phosphoenolpyruvate carboxykinase [PEPCK] and glucose-6-phosphatase [G6Pase]). Further in vivo assays showed that lentivirus-mediated hepatic knockdown of Gm10804 alleviated hepatic steatosis and lipid accumulation, and decreased expression of hepatic PEPCK, G6Pase, SREBP-1c and FAS in DM-NAFLD mice. In summary, Gm10804 knockdown attenuates hepatic lipid accumulation by ameliorating disorders of hepatic glucose and lipid metabolism in DM-NAFLD. SIGNIFICANCE OF THE STUDY: We first discovered that Gm10804 knockdown attenuated hepatic lipid accumulation by ameliorating disorders of hepatic glucose and lipid metabolism in DM-NAFLD. These results help to understand the pathogenesis and development of DM-NAFLD and provide some clues for further understanding the regulation of lncRNAs in glucose and lipid metabolism.

5.
Environ Res ; 183: 109189, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32050127

RESUMO

BACKGROUNDS: Seasonal influenza remains epidemic globally with a substantial health burden. Understanding the transmission patterns and epidemic features of influenza may facilitate the improvement of preventive and control measures. This study aims to assess the epidemic features of influenza among different climate zones and identify high-risk zones across Gansu province, China. METHODS: We collected weekly influenza cases at county-level between 1st January 2012 and 31st December 2016, as well as climate zones classification shapefile data from Köppen-Geiger climate map. We compared the epidemic features (Frequency index (α), Duration index (ß) and Intensity index (γ)) of influenza among different climate zones. Spatial cluster analysis was used to examine the high-risk areas of transmission of influenza. RESULTS: The distribution of cases existed significant differences among eight climate zones (F-test: 267.02, p < 0.05). The highest mean weekly incidence rate (per 100,000 population) was 0.59 in snow climate with dry winter and warm summer (Dwb). The primary (relative risk (RR): 3.61, p < 0.001) and secondary (RR: 2.45, p < 0.001) clusters were located in Dwb. The highest values of α, ß and γ were 1.00, 261 and 154.38 in Dwb. The hot spots (high-high clusters) of the epidemic indices were detected in Dwb. CONCLUSIONS: This study found the variability of epidemic features of influenza among eight climate zones. We highlight that Dwb was the high-risk zone where influenza clustered with the highest incidence rate and epidemic temporal indices. This provide further insight into potential improvement of preventive measures by climate zones to minimize the impact of epidemics.

6.
Oxid Med Cell Longev ; 2020: 2468031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104528

RESUMO

Mitochondrial dysfunction and oxidative stress play an important role in the pathogenesis of both atrial fibrillation (AF) and diabetes mellitus (DM). Wenxin Keli (WXKL), an antiarrhythmic traditional Chinese medicine, has been shown to prevent cardiac arrhythmias through modulation of cardiac ion channels. This study tested the hypothesis that WXKL can improve atrial remodeling in diabetic rats by restoring mitochondrial function. Primary atrial fibroblasts of neonatal SD rats were divided into four groups: control, hydrogen peroxide (H2O2), H2O2+WXKL 1 g/L, and H2O2+WXKL 3 g/L groups. Intracellular mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and mitochondrial oxygen consumption were measured. SD male rats were randomly divided into three groups: control, DM, and DM+WXKL groups. Rats in the DM+WXKL group were treated with daily gavage of WXKL at 3 g/kg. After eight weeks, echocardiography, hemodynamic examination, histology, electrophysiology study, mitochondrial respiratory function, and western blots were assessed. H2O2 treatment led to increased ROS and decreased intracellular MMP and mitochondrial oxygen consumption in primary atrial fibroblasts. WXKL improved the above changes. DM rats showed increased atrial fibrosis, greater left atrial diameter, lower atrial conduction velocity, higher conduction heterogeneity, higher AF inducibility, and lower mitochondrial protein expression, and all these abnormal changes except for left atrial diameter were improved in the DM+WXKL group. WXKL improves atrial remodeling by regulating mitochondrial function and homeostasis and reducing mitochondrial ROS in diabetic rats.

7.
Mol Biol Rep ; 47(3): 2181-2187, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32072405

RESUMO

Recent research have proved that miR-501-5p acted as a potent tumor biomarker in several cancers, excluding head and neck squamous cell carcinoma (HNSCC). The study intends to discover the potential function and mechanism of miR-501-5p in HNSCC. Data from TCGA database and qRT-PCR estimated the expression of miR-501-5p and Calcium activated Chloride Channel A4 (CLCA4). Cell proliferation, clone formation and transwell assays were performed to explore HNSCC cells biological behaviors. Luciferase assay was carried out to identify the interaction between miR-501-5p and CLCA4. miR-501-5p was profoundly up-regulated in HNSCC samples and promoted cells proliferation and metastasis. CLCA4, as a target of miR-501-5p, was connected with worse outcomes in HNSCC patients. Co-transfection assay proved that miR-501-5p/CLCA4 functioned as crucial regulators to affect HNSCC cells biological behaviors. Our study illustrated that miR-501-5p exhibited a tumor-promoting role on HNSCC by targeting CLCA4, providing a new insight for revealing the pathogenesis and treatment of HNSCC.

8.
Neurol Res ; 42(3): 222-227, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32024457

RESUMO

Background: Glioblastoma (GBM) is recognized as a malignant brain tumor with frequent mortality. Extensive evidence indicated that miR-188-3p exerts an important role in various tumors. However, the role of miR-188-3p in GBM has not been elucidated. The purpose of the present investigation was to explore the biological effect of miR-188-3p, as well as to determine its target gene in GBM.Methods: The miR-188-3p and G Protein-Coupled Receptor 26 (GPR26) expressional profiles were obtained from The Cancer Genome Atlas (TCGA) database. The proliferative ability, invasive and migratory capabilities of GBM cells were measured using Cell Counting Kit-8 and transwell assays. Bioinformatics tool and luciferase reporter gene analysis were utilized to assess the correlation between miR-188-3p and GPR26. Reverse transcription-quantitative polymerase chain reaction (RT-PCR) and western blotting were performed to detect the indicated gene expression.Results: MiR-188-3p expression was highly regulated in GBM tissue and cell lines, while GPR26 was significantly decreased in GBM. Depletion of miR-188-3p significantly retarded the cell proliferation, invasion and migration in the U-87 MG cell. Luciferase reporter gene assay showed that GPR26 was a target gene of miR-188-3p in GBM. The expression of GPR26 was negatively regulated by miR-188-3p. The inhibitory effect of miR-188-3p inhibitor on cell behaviors was further strengthened by the overexpression of GPR26 in GBM.Conclusion: These findings provided evidence for the cancer-promoting effect of miR-188-3p in GBM cells and demonstrated that GPR26 was directly targeted by miR-188-3p, which might contribute to the therapeutic therapy of GBM.

9.
Cancer Epidemiol Biomarkers Prev ; 29(3): 650-658, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31915141

RESUMO

BACKGROUND: There is little information on human exposure to carcinogens and other toxicants related to opiate use, alone or in combination with tobacco. METHODS: Among male participants of the Golestan Cohort Study in Northeast Iran, we studied 28 never users of either opiates or tobacco, 33 exclusive cigarette smokers, 23 exclusive users of smoked opiates, and 30 opiate users who also smoked cigarettes (dual users; 21 smoked opiates and 9 ingested them). We quantified urinary concentrations of 39 exposure biomarkers, including tobacco alkaloids, tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons (PAH), and volatile organic compounds (VOC), and used decomposition to parse out the share of the biomarker concentrations explained by opiate use and nicotine dose. RESULTS: Dual users had the highest concentrations of all biomarkers, but exclusive cigarette smokers and exclusive opiate users had substantially higher concentrations of PAH and VOC biomarkers than never users of either product. Decomposition analysis showed that opiate use contributed a larger part of the PAH concentrations than nicotine dose, and the sum of 2- and 3-hydroxyphenanthrene (∑2,3-phe) resulted almost completely from opiate use. Concentrations of most VOC biomarkers were explained by both nicotine dose and opiate use. Two acrylamide metabolites, a 1,3-butadiene metabolite and a dimethylformamide metabolite, were more strongly explained by opiate use. Acrylamide metabolites and ∑2,3-phe were significantly higher in opiate smokers than opiate eaters; other biomarkers did not vary by the route of opiate intake. CONCLUSIONS: Both cigarette smokers and opiate users (by smoking or ingestion) were exposed to many toxicants and carcinogens. IMPACT: This high exposure, particularly among dual opiate and cigarette users, can have a substantial global public health impact.

11.
J Am Chem Soc ; 142(3): 1465-1474, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31904234

RESUMO

Achieving efficient charge transfer at small frontier molecular orbital offsets between donor and acceptor is crucial for high performance polymer solar cells (PSCs). Here we synthesize a new wide band gap polymer donor, PTQ11, and a new low band gap acceptor, TPT10, and report a high power conversion efficiency (PCE) PSC (PCE = 16.32%) based on PTQ11-TPT10 with zero HOMO (the highest occupied molecular orbital) offset (ΔEHOMO(D-A)). TPT10 is a derivative of Y6 with monobromine instead of bifluorine substitution, and possesses upshifted lowest unoccupied molecular orbital energy level (ELUMO) of -3.99 eV and EHOMO of -5.52 eV than Y6. PTQ11 is a derivative of low cost polymer donor PTQ10 with methyl substituent on its quinoxaline unit and shows upshifted EHOMO of -5.52 eV, stronger molecular crystallization, and better hole transport capability in comparison with PTQ10. The PSC based on PTQ11-TPT10 shows highly efficient exciton dissociation and hole transfer, so that it demonstrates a high PCE of 16.32% with a higher Voc of 0.88 V, a large Jsc of 24.79 mA cm-2, and a high FF of 74.8%, despite the zero ΔEHOMO(D-A) value between donor PTQ11 and acceptor TPT10. The PCE of 16.32% is one of the highest efficiencies in the PSCs. The results prove the feasibility of efficient hole transfer and high efficiency for the PSCs with zero ΔEHOMO(D-A), which is highly valuable for understanding the charge transfer process and achieving high PCE of PSCs.

12.
ACS Appl Mater Interfaces ; 12(1): 1628-1639, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31800210

RESUMO

Many natural materials, such as silk, animal bone, nacre, and plant fibers, achieve outstanding strength and toughness through the rupture of sacrificial bonds between chain segments in the organic phase. In this work, we present a bioinspired strategy to fabricate silk fibroin-based hydrophobic-association (HA) hydrogels by incorporating the hydrophobic interaction as a sacrificial bond into the alginate ionic network, which not only enhanced the mechanical extensibility, strength, and toughness of the hydrogels but also enabled self-recovery and self-healing properties via reversible hydrophobic interactions without external stimuli at room temperature. The hydrophobic interaction system consisted of the hydrophobic monomer stearyl methacrylate (C18M) and an amphiphilic regenerated silk fibroin (RSF) solution. The mechanical tests and rheometry indicated that the hydrophobic interaction served as the sacrificial bond that preferentially ruptures prior to the alginate ionic network under an external load, which dissipated enormous amounts of energy and conferred an improved mechanical performance. Moreover, the structure of HA gels could be quickly recovered after injection due to the existence of hydrophobic interactions. In addition, the degradability of the HA gels in a protease XIV solution was strongly dependent upon the C18M component, which significantly promoted the degradation rate of HA gels. The biomimetic mineralization process of HA gels within a simulated body fluid (SBF), mimicking the inorganic composition of human blood plasma, was performed and the calcium phosphate nanoparticles on the hydrogel were observed. Importantly, in vivo experiments illustrated that the HA gels exhibited satisfactory biocompatibility, and the mouse osteoblasts (MC3T3-E1) could attach and spread on the hydrogels. Overall, the self-healing, biocompatibility, and high mechanical properties of the HA gels render them potentially suitable for load-bearing applications in drug delivery or other soft tissue-engineering applications.

13.
Thromb Res ; 185: 78-84, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31778944

RESUMO

INTRODUCTION: Therapeutic plasma exchange (TPE) is mainstay therapy for thrombotic thrombocytopenic purpura (TTP). However, it remains controversial if ABO type influences diagnosis or time to remission. MATERIALS AND METHODS: We investigated if ABO type influences length of TPE regimen in TTP patients with ADAMTS13 deficiency at our institution. Seventy out of 71 patients with suspected TTP who had ADAMTS13 activity measured were included. ADAMTS13 activity <10% defined those with idiopathic/acquired TTP (41/70). RESULTS: We found that among patients with ADAMTS13 deficiency, non-O patients required a significantly greater number of TPE (NoP) compared to O patients (p = 0.039). Additionally, patients with ADAMTS13 deficiency regardless of ABO type needed more TPE to achieve platelet recovery compared to those patients without deficiency (p = 0.00002). In regard to other variables that may affect response to therapy in TTP patients, we found no association between obesity and NoP; however, obesity rate was higher among ADAMTS13 deficient patients compared to overall obesity rate of our regional general population. Likewise, were found that blood group O did not occur with greater frequency in our cohort. CONCLUSIONS: Our data indicates that ABO may affect the NoP patients required for disease remission. We found that non-O patients needed more procedures to overcome their disease. Further work with greater number of patients will be needed to determine if specific non-O blood types require more procedures to recover their platelet count.

14.
Peptides ; 123: 170200, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31730792

RESUMO

Apoptosis induced by oxidative stress is one of the most important cardiomyocytes losses during ischemia-reperfusion (I/R). Catestatin (CST) has been demonstrated to have the anti-oxidative capacity in vitro. We hypothesized that CST intervention could reduce apoptosis of cardiomyocytes induced by oxidative stress in I/R. In Langendorff-perfused rat heart global I/R model, CST was introduced at the reperfusion stage. In comparison to the control group, CST led to preservation on activities of superoxide dismutase and glutathione peroxidase, improvement of hemodynamics, and reduced infarction area in reperfused myocardium. The protection of CST was also shown by less apoptotic cardiomyocytes in TUNEL staining, less caspase-3 activation, and increased phosphorylation of protein kinase B (PKB/Akt) in Western blot. To further demonstrate the benefits of CST and explore the possible underlying mechanism, H2O2-challenged primary-cultured neonatal rat cardiomyocytes were used to simulate the oxidative-stressed scenario. CST incubation with the H2O2-challenged cardiomyocytes led to reduction of apoptosis, which was demonstrated by less Hoechst 33342 positive staining of nuclei, less caspase-3 activation, and DNA fragmentation. The effect of CST was abrogated by pretreatment of the cardiomyocytes with the PI3K inhibitor LY294002. Furthermore, Akt activation and the anti-apoptosis effect of CST were abolished by pretreatment of the cardiomyocytes with ß2 receptor inhibitor ICI118551. Thus, the salvage of oxidative-stress-induced apoptotic cardiomyocytes in I/R by CST might involve activation ß2 receptor and regulation of PI3K/Akt signaling in reperfusion injury salvage kinase (RISK) pathway.

15.
Acta Biochim Biophys Sin (Shanghai) ; 52(1): 49-57, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31828293

RESUMO

Gastric cancer (GC) is one of malignant tumors with high mortality and morbidity in the world. MicroRNA-122 (miR-122) acts as a tumor suppressor in a variety of cancers and has been found to be dominant in gastric adenocarcinoma. However, the specific biological function of miR-122-5p in GC is not completely clear. In this study, we found that miR-122-5p was low-expressed in GC tissues and cell lines by using qRT-PCR. Overexpression of miR-122-5p inhibited the proliferation, migration, and invasion of GC cells by using CCK-8 and transwell assays. On the contrary, downregulation of miR-122-5p promoted the proliferation, migration, and invasion of GC cells. In addition, we found that the expression of LYN, an Src family tyrosine kinase, was inversely correlated with miR-122-5p expression in GC tissues by using western blot analysis, immunohistochemistry, and qRT-PCR assays. Meanwhile, luciferase assay results indicated that LYN is a direct target of miR-122-5p in GC cells. Moreover, silencing LYN expression by its siRNA inhibited the proliferation, migration, and invasion of GC cells. Importantly, overexpression of LYN restored miR-122-5p-mediated inhibition of the proliferation, migration, and invasion of GC cells. Taken together, our results indicated miR-122-5p inhibited the proliferation, migration, and invasion by targeting LYN in GC.


Assuntos
Movimento Celular/genética , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Neoplasias Gástricas/metabolismo , Quinases da Família src/genética , Quinases da Família src/metabolismo , Regiões 3' não Traduzidas/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Mimetismo Molecular/genética , Mutação , RNA Interferente Pequeno/genética , Neoplasias Gástricas/patologia , Transfecção
16.
Huan Jing Ke Xue ; 41(1): 330-336, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854934

RESUMO

This study uses three different operating phases for a sequencing batch reactor (SBR) combined with an anaerobic baffled reactor (ABR) to determine the effect of deep nitrogen and carbon removal by the "partial nitrification-anaerobic ammonium oxidation combined denitrification" (termed PN-SAD) reaction. The effluent of the SBR (NO2--N/NH4+-N ratio range of 1-1.32) was accessed directly to the single compartment ABR anammox system in phase Ⅰ. The results showed that although the anammox reaction was stable, the combined process total nitrogen (TN) removal efficiency was<80%, and the TN concentration of effluent was~20 mg·L-1. In order to increase the denitrification function in the ABR, denitrifying sludge was added to the third compartment of the ABR in phase Ⅱ. We found that the TN removal efficiency of the coupling reaction was still low. An organic carbon source should be supplied in the latter stage of anammox if deep nitrogen removal is required. Therefore, in phase Ⅲ, the effluent of the SBR (NO2--N/NH4+-N ratio of ~5) was mixed with the partial raw water (mixed water NO2--N/NH4+-N ratio of ~1.4; C/N ratio of 2.5). The mixed water was connected to the single compartment of the ABR. The PN-SAD system not only achieved a good matrix ratio at the anammox stage, but also provided a good carbon source for denitrification. The chemical oxygen demand (COD) concentration of the effluent in the whole process was 50 mg·L-1, the TN concentration of the effluent was<6 mg·L-1, and the TN removal efficiency was 95%. We conclude that the stable operation of the combined PN-SAD reaction provides the basis for deep nitrogen and carbon removal using the combined SBR-ABR process.

18.
Huan Jing Ke Xue ; 40(11): 5182-5190, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854588

RESUMO

In-situ measurement of nitrous oxide (N2O) and methane (CH4) emissions in a typical paddy-cowpea rotation system in Southern Hainan was conducted to determine the characteristics of greenhouse gas emissions under different optimum fertilization treatments. The experiment consisted of 5 treatments:conventional farming fertilization (CON), optimized fertilization (OPT), organic-inorganic fertilization (ORG), slow-controlled optimization fertilization (SCOPT), and no nitrogen as the control (CK). The N2O and CH4 emissions were measured using static chamber-gas chromatography during the all the paddy-cowpea rotation seasons. Global warming potential (GWP) and greenhouse gas intensity (GHGI) were also estimated in this study. The cumulative N2O emission during the rice growth season was 0.19-1.37 kg·hm-2. Compared with the CON treatment, other treatments reduced N2O emission by 50% to 86%. The cumulative N2O emission during the cowpea growth season was 1.29-3.55 kg·hm-2. In addition, N2O emission increased by 14% as a result of the ORG treatment, whereas that of the remaining treatments decreased by 16% to 59%. The cumulative CH4 emissions during the paddy growth season were 4.67-14.23 kg·hm-2. The CH4 emissions following the CK, OPT, and ORG treatments were higher by 116%, 22%, and 102%, respectively, whereas that of SCOPT was lower by 29%, than that following the CON treatment. Moreover, the cumulative CH4 emission during the cowpea growth season was 0.03-0.26 kg·hm-2, and CH4 absorption occurred during the same period. With regard to the contribution rate of different periods to GWP, the cowpea growth season still had a proportion of 44.7%-54.5%, despite extremely low CH4 emission. Regarding the two greenhouse gases, N2O contributed 66.7%-77.2%. During the entire rotation system, both GWP and GHGI processed by SCOPT were significantly lower than those of the CON treatments. To sum up, the SCOPT treatment was determined to be the optimal fertilization scheme in this study and had the most significant effects on increasing production and reducing greenhouse gas emissions.

19.
Adv Mater ; 31(52): e1905480, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867848

RESUMO

Four low-cost copolymer donors of poly(thiophene-quinoxaline) (PTQ) derivatives are demonstrated with different fluorine substitution forms to investigate the effect of fluorination forms on charge separation and voltage loss (Vloss ) of the polymer solar cells (PSCs) with the PTQ derivatives as donor and a A-DA'D-A-structured molecule Y6 as acceptor. The four PTQ derivatives are PTQ7 without fluorination, PTQ8 with bifluorine substituents on its thiophene D-unit, PTQ9, and PTQ10 with monofluorine and bifluorine substituents on their quinoxaline A-unit respectively. The PTQ8- based PSC demonstrates a low power conversion efficiency (PCE) of 0.90% due to the mismatch in the highest occupied molecular orbital (HOMO) energy levels alignment between the donor and acceptor. In contrast, the devices based on PTQ9 and PTQ10 show enhanced charge-separation behavior and gradually reduced Vloss , due to the gradually reduced nonradiative recombination loss in comparison with the PTQ7-based device. As a result, the PTQ10-based PSC demonstrates an impressive PCE of 16.21% with high open-circuit voltage and large short-circuit current density simultaneously, and its Vloss is reduced to 0.549 V. The results indicate that rational fluorination of the polymer donors is a feasible method to achieve fast charge separation and low Vloss simultaneously in the PSCs.

20.
Cardiovasc Diabetol ; 18(1): 165, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779619

RESUMO

BACKGROUND: Diabetes mellitus is an important risk factor for atrial fibrillation (AF) development. Sodium-glucose co-transporter-2 (SGLT-2) inhibitors are used for the treatment of type 2 diabetes mellitus (T2DM). Their cardioprotective effects have been reported but whether they prevent AF in T2DM patients are less well-explored. We tested the hypothesis that the SGLT-2 inhibitor, empagliflozin, can prevent atrial remodeling in a diabetic rat model. METHODS: High-fat diet and low-dose streptozotocin (STZ) treatment were used to induce T2DM. A total of 96 rats were randomized into the following four groups: (i) control (ii) T2DM, (iii) low-dose empagliflozin (10 mg/kg/day)/T2DM; and (iv) high-dose empagliflozin (30 mg/kg/day)/T2DM by the intragastric route for 8 weeks. RESULTS: Compared with the control group, left atrial diameter, interstitial fibrosis and the incidence of AF inducibility were significantly increased in the DM group. Moreover, atrial mitochondrial respiratory function, mitochondrial membrane potential, and mitochondrial biogenesis were impaired. Empagliflozin treatment significantly prevented the development of these abnormalities in DM rats, likely via the peroxisome proliferator-activated receptor-c coactivator 1α (PGC-1α)/nuclear respiratory factor-1 (NRF-1)/mitochondrial transcription factor A (Tfam) signaling pathway. CONCLUSIONS: Empagliflozin can ameliorate atrial structural and electrical remodeling as well as improve mitochondrial function and mitochondrial biogenesis in T2DM, hence may be potentially used in the prevention of T2DM-related atrial fibrillation.

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