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1.
Nature ; 623(7987): 531-537, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37853122

RESUMO

Achieving both high efficiency and long-term stability is the key to the commercialization of perovskite solar cells (PSCs)1,2. However, the diversity of perovskite (ABX3) compositions and phases makes it challenging to fabricate high-quality films3-5. Perovskite formation relies on the reaction between AX and BX2, whereas most conventional methods for film-growth regulation are based solely on the interaction with the BX2 component. Herein, we demonstrate an alternative approach to modulate reaction kinetics by anion-π interaction between AX and hexafluorobenzene (HFB). Notably, these two approaches are independent but work together to establish 'dual-site regulation', which achieves a delicate control over the reaction between AX and BX2 without unwanted intermediates. The resultant formamidinium lead halides (FAPbI3) films exhibit fewer defects, redshifted absorption and high phase purity without detectable nanoscale δ phase. Consequently, we achieved PSCs with power conversion efficiency (PCE) up to 26.07% for a 0.08-cm2 device (25.8% certified) and 24.63% for a 1-cm2 device. The device also kept 94% of its initial PCE after maximum power point (MPP) tracking for 1,258 h under full-spectrum AM 1.5 G sunlight at 50 ± 5 °C. This method expands the range of chemical interactions that occur in perovskite precursors by exploring anion-π interactions and highlights the importance of the AX component as a new and effective working site to improved photovoltaic devices with high quality and phase purity.

2.
Nature ; 573(7772): 83-86, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31485059

RESUMO

Quasars, which are exceptionally bright objects at the centres (or nuclei) of galaxies, are thought to be produced through the accretion of gas into disks surrounding supermassive black holes1-3. There is observational evidence at galactic and circumnuclear scales4 that gas flows inwards towards accretion disks around black holes, and such an inflow has been measured at the scale of the dusty torus that surrounds the central accretion disk5. At even smaller scales, inflows close to an accretion disk have been suggested to explain the results of recent modelling of the response of gaseous broad emission lines to continuum variations6,7. However, unambiguous observations of inflows that actually reach accretion disks have been elusive. Here we report the detection of redshifted broad absorption lines of hydrogen and helium atoms in a sample of quasars. The lines show broad ranges of Doppler velocities that extend continuously from zero to redshifts as high as about 5,000 kilometres per second. We interpret this as the inward motion of gases at velocities comparable to freefall speeds close to the black hole, constraining the fastest infalling gas to within 10,000 gravitational radii of the black hole (the gravitational radius being the gravitational constant multiplied by the object mass, divided by the speed of light squared). Extensive photoionization modelling yields a characteristic radial distance of the inflow of approximately 1,000 gravitational radii, possibly overlapping with the outer accretion disk.

3.
Opt Lett ; 49(4): 834-837, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359194

RESUMO

In this Letter, we design and experimentally demonstrate compact mode converters with a lightning-like and arrow-like polygonal subwavelength grating (SWG) structure on a silicon-on-insulator (SOI) platform, which can convert the TE0 mode to the TE1 and TE2 modes, respectively. The footprints of the proposed TE0-1 and TE0-2 mode converters are only 4.44 × 1.3 and 5.89 × 1.8 µm2, respectively. The experimental results show the mode converters have a low insertion loss (<1 dB) and a broad bandwidth (>50 nm). The measured cross talks of the TE0-1 and TE0-2 mode converters are -7.2 dB and -10.3 dB, respectively. In addition, the proposed mode converters with the SWG structure have the advantage in fabrication, since only a one-step full-etching process is required.

4.
Chin Med Sci J ; 39(2): 149-154, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38773789

RESUMO

Vertebral artery dissection is a rare pathology that can cause ischemic stroke in young people. Cervical massage, especially improper pulling manipulation, is a cause of vertebral artery dissection. We present a case of 32-year-old woman who developed acute multiple posterior circulation ischemic cerebral infarctions as a result of left vertebral artery V4 segment dissection after receiving neck massage. She underwent emergency vertebral artery stent implantation at the site of the dissection. Symptoms were relieved the day after treatment. The patient recovered without adverse complications or endovascular restenosis in the following year.


Assuntos
Infarto Cerebral , Massagem , Stents , Dissecação da Artéria Vertebral , Humanos , Feminino , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/etiologia , Dissecação da Artéria Vertebral/cirurgia , Adulto , Stents/efeitos adversos , Massagem/efeitos adversos , Infarto Cerebral/etiologia , Infarto Cerebral/diagnóstico por imagem , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia
5.
Opt Express ; 31(4): 6577-6589, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823910

RESUMO

The traveling-wave like Fabry-Perot (F-P) resonators based on transverse-mode-conversion have been extensively studied as on-chip filters. However, the incomplete transverse mode conversion will lead to the coupling between two degenerated resonant modes, which brings additional loss and may further induce the resonance splitting. In this paper, we take the transverse-mode-conversion based resonator with anti-symmetric nanobeam Bragg reflector as an example and study the resonant mode coupling in both the direct-coupled and side-coupled resonators. The coupled mode equations are used to model the incomplete transverse mode conversion of Bragg reflector. The resonant mode coupling can be effectively suppressed by carefully designing the phase shifter length and adding the tapered holes. The insertion loss of less than -1 dB can be achieved in the simulation using the two methods. This work is believed to benefit the design of mode-conversion based resonators with low insertion loss and non-splitting line shape.

6.
Int J Equity Health ; 22(1): 42, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899382

RESUMO

BACKGROUND: Health literacy has always been considered as an important factor to promote people's health, but does it have a significant effect on health across all social strata and especially lower social strata? This study aims to analyze the influences of health literacy on health outcomes of different social strata, and then infer whether improving health literacy can reduce health disparities among different social strata. METHODS: Utilizing health literacy monitoring data from a city in Zhejiang Province in 2020, the samples are divided into three social strata according to the socioeconomic status score: low, middle and high social stratum, to compare whether there are significant differences in health outcomes between population with lower and higher health literacy among different social strata. In the strata with significant differences, control the confounding factors to further verify the influence of health literacy on health outcomes. RESULTS: In low and middle social strata, there are significant differences between population with lower and higher health literacy, when considering the two types of health outcomes (chronic diseases and self-rated health), but in high social stratum, this difference is not significant. After controlling the relevant variables, the influence of health literacy on the prevalence of chronic diseases is statistically significant only in low social stratum, and the health literacy is negatively correlated with the prevalence of chronic diseases(OR = 0.722, P = 0.022). In addition, there are statistical significances for positive impact of health literacy on self-rated health in both low and middle social strata (OR = 1.285, P = 0.047; OR = 1.401, P = 0.023). CONCLUSION: Compared with high social stratum, the influence of health literacy on health outcomes of low social stratum (chronic diseases) or both middle and low social strata (self-rated health) is more significant, and both are to improve the health outcomes. This finding suggests that improving residents' health literacy may be an effective way to alleviate the health disparities among different social strata.


Assuntos
Letramento em Saúde , Classe Social , Humanos , China , Doença Crônica , Avaliação de Resultados em Cuidados de Saúde
7.
Phys Chem Chem Phys ; 25(9): 6780-6789, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36789729

RESUMO

The "gold standard" CCSD(T) method is adopted along with the correlation consistent basis sets up to aug-cc-pV5Z-PP to study the mechanism of the hydrogen abstraction reaction H2Te + OH. The predicted geometries and vibrational frequencies for reactants and products are in good agreement with the available experimental results. With the ZPVE corrections, the transition state in the favorable pathway of this reaction energetically lies 1.2 kcal mol-1 below the reactants, which is lower than the analogous relative energies for the H2Se + OH reaction (-0.7 kcal mol-1), the H2S + OH reaction (+0.8 kcal mol-1) and the H2O + OH reaction (+9.0 kcal mol-1). Accordingly, the exothermic reaction energies for these related reactions are predicted to be 47.8 (H2Te), 37.7 (H2Se), 27.1 (H2S), and 0.0 (H2O) kcal mol-1, respectively. Geometrically, the low-lying reactant complexes for H2Te + OH and H2Se + OH are two-center three-electron hemibonded structures, whereas those for H2S + OH and H2O + OH are hydrogen-bonded. With ZPVE and spin-orbit coupling corrections, the relative energies for the reactant complex, transition state, product complex, and the products for the H2Te + OH reaction are estimated to be -13.1, -1.0, -52.0, and -52.6 kcal mol-1, respectively. Finally, twenty-eight DFT functionals have been tested systematically to assess their ability in describing the potential energy surface of the H2Te + OH reaction. The best of these functionals for the corresponding energtics are -9.9, -1.4, -46.4, and -45.4 kcal mol-1 (MPWB1K), or -13.1, -2.4, -57.1, and -54.6 kcal mol-1 (M06-2X), respectively.

8.
Environ Res ; 216(Pt 2): 114584, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36270532

RESUMO

Eukaryotic plankton are pivotal members of marine ecosystems playing crucial roles in marine food webs and biogeochemical cycles. However, understanding the patterns and drivers of their community assembly remains a grand challenge. A study was conducted in the northern South China Sea (SCS) to address this issue. Here, 49 samples were collected and size-fractionated from discrete depths at continental shelf and continental slope in the northern SCS over a diel cycle. From high throughput sequencing of the 18S rDNA gene V4 region, 2463 operational taxonomic units (OTUs) were retrieved. Alveolata and Opisthokonta overwhelmingly dominated the assemblages in the abundance (44.76%, 31.08%) and species richness (59%, 12%). Biodiversity was higher in the slope than the shelf and increased with depth. Temperature and salinity appeared to be the most important deterministic drivers of taxon composition. Community structure was influenced by multiple factors in the importance order of: environmental factors (temperature + salinity) > spatial factor > water depth > sampling time. Furthermore, the neutral model explained more variations in the smaller-sized (0.22-3 µm) community (24%) than larger-sized (3-200 µm) community (16%) but generally explained less variations than did deterministic processes. Additionally, our data indicated that the larger plankton might be more environmentally filtered and less plastic whereas the smaller plankton had stronger dispersal ability. This study sheds light on the differential contributions of the deterministic process and stochastic process and complexities of assembly mechanisms in shaping the community assembly of micro-nano and pico-eukaryotic biospheres in a subtropical ocean.


Assuntos
Eucariotos , Plâncton , Plâncton/genética , Eucariotos/genética , Ecossistema , Biodiversidade , Salinidade , China
9.
BMC Public Health ; 23(1): 2355, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017398

RESUMO

OBJECTIVE: This study explored the relationship between smokers' health literacy, knowledge of smoking hazards, and their intention to quit. METHODS: Based on data from the 2019 Health Literacy and Tobacco Use Surveillance among residents of a city in Zhejiang Province, 1120 male smokers were screened. Differential tests were used to analyze whether smokers with varying levels of health literacy and knowledge about smoking hazards differed in their intention to quit smoking and the intensity of their intention. A multi-factor logistic regression model was constructed to explore the extent of these differences. RESULTS: Only 24.8% of smokers had higher health literacy. Among smokers, those with an intention to quit had a higher health literacy level compared to those without such intention (32.7% vs. 17.0%, p < 0.001). Health literacy levels did not differ significantly between groups with different intensity of intention to quit (34.2% vs. 31.9% vs. 30.1%, p = 0.435). About 48.7% of the smokers a higher level of knowledge about smoking hazards. It was more prevalent in the intent to quit group compared to the no intent to quit group (54.0% vs. 43.4%, p < 0.001), and the low intent to quit group had lower knowledge compared to the moderate and high intent to quit groups (49.1% vs. 56.6% vs. 63.4%, p = 0.011). After adjusting for other influences, smokers with lower health literacy were less likely to have intention to quit (OR = 0.659, p = 0.016). And the association between knowledge about smoking hazards and whether smokers have the intention to quit is no longer significant, but it significantly affects the intensity of the intention to quit among smokers who already have the intention (OR = 0.623, p = 0.005). CONCLUSION: General health literacy may play a role in facilitating smokers' progression from the stage of no intent to quit to one of intent to quit, but a more specific understanding of the harms of smoking may be needed to increase the strength of intent to quit.


Assuntos
Letramento em Saúde , Abandono do Hábito de Fumar , Humanos , Masculino , Intenção , Fumar/epidemiologia , China/epidemiologia
10.
Angew Chem Int Ed Engl ; 62(24): e202303176, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37060295

RESUMO

Possessed with advantageous optoelectronic properties, perovskites have boosted the rapid development of solution-processed solar cells. The performance of perovskite solar cells (PSCs) is significantly weakened by the carrier loss at grain boundary grooves (GBGs); however, it receives limited attention and there lacks effective approach to solve this issue. Herein, for the first time, we constructed the tungstate/perovskite heterointerface via a "two step" in situ reaction approach that provides effective defect passivation and ensures efficient carrier dynamics at the GBGs. The exposed perovskite at grain boundaries is converted to wide-band-gap PbWO4 via an in-situ reaction between Pb2+ and tungstate ions, which passivate defects due to the strong ionic bonding. Moreover, recombination loss is further suppressed via the heterointerface energetics modification based on an additional transformation from PbWO4 to CaWO4 . PSCs based on this groove modification strategy showed good universality in both normal and inverted structure, with an improved efficiency of 23.25 % in the n-i-p device and 23.33 % in the p-i-n device. Stable power output of the modified device could maintain 91.7 % after around 1100 h, and the device efficiency could retain 92.5 % after aging in air for around 2110 h, and 93.1 % after aging at 85 °C in N2 for 972 h.

11.
J Appl Clin Med Phys ; 23(1): e13479, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34846098

RESUMO

The Varian Ethos system allows for online adaptive treatments through the utilization of artificial intelligence (AI) and deformable image registration which automates large parts of the anatomical contouring and plan optimization process. In this study, treatments of intact prostate and prostate bed, with and without nodes, were simulated for 182 online adaptive fractions, and then a further 184 clinical fractions were delivered on the Ethos system. Frequency and magnitude of contour edits were recorded, as well as a range of plan quality metrics. From the fractions analyzed, 11% of AI generated contours, known as influencer contours, required no change, and 81% required minor edits in any given fraction. The frequency of target and noninfluencer organs at risk (OAR) contour editing varied substantially between different targets and noninfluencer OARs, although across all targets 72% of cases required no edits. The adaptive plan was the preference in 95% of fractions. The adaptive plan met more goals than the scheduled plan in 78% of fractions, while in 15% of fractions the number of goals met was the same. The online adaptive recontouring and replanning process was carried out in 19 min on average. Significant improvements in dosimetry are possible with the Ethos online adaptive system in prostate radiotherapy.


Assuntos
Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Inteligência Artificial , Humanos , Masculino , Órgãos em Risco , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
12.
J Therm Biol ; 104: 103203, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35180950

RESUMO

Temperature is a considerable stressor in aquatic environments. The objective of this study was to investigate the changes in endogenous compounds of flounder (Paralichthys olivaceus) at different temperatures based on a holistic metabolomic and lipidomic analysis. Accordingly, this study involved reversed-phase chromatography and hydrophilic interaction chromatography coupled with a mass spectrometry detection platform, and using a new database, and multivariate statistical analysis. In total, 954 unique masses were obtained, including 495 metabolites and 459 lipids, and 53 qualified differential metabolites were filtered. Specifically, among the highlighted biomarkers, 2'-Hydroxy-5'-methylacetophenone and FFA (17:1) were the metabolites and lipids with the largest Log2FC, respectively. In addition, 18-Hydroxycorticosterone showed the greatest downregulation. Hypoxia-inducible factor 1 signaling pathway, biosynthesis of amino acids, glycerophospholipid metabolism, and choline metabolism in cancer were enriched and noteworthy metabolic pathways, which were closely related. Overall, this study provides potential serum biomarkers and metabolic pathways for flounder as well as a reference for further studies on the physiological functions of flounder under different stressors.


Assuntos
Linguado/metabolismo , Lipidômica , Metabolômica , Temperatura , Animais , Biomarcadores/metabolismo , Redes e Vias Metabólicas
13.
Small ; 17(7): e2006387, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33475246

RESUMO

Solution-processed zinc oxide (ZnO) is one of the widely used electron transporting layers (ETLs) for organic solar cells (OSCs). However, low optical transparency along with thickness-sensitivity of ZnO ETL constrains the improvement of photovoltaic performance and large-scale fabrication compatibility. To resolve these issues, zirconium (Zr) doping is applied to tailor the optoelectronic and morphological properties of ZnO layer. This approach not only improves light transmittance with the suppressed parasitic absorption, but also provides an optimized surface morphology for enhancing charge extraction property and reducing potential of charge trap-assisted recombination. By using ZnO:Zr as ETL in inverted device configuration, the maximum power conversion efficiency (PCE) of PM6:Y6:PC71 BM solar cell devices is up to 17.2%, which makes an enhancement of 9.55% compared to ZnO-based devices (15.7%). As the thickness of ZnO:Zr ETL increases to ≈60 nm, the presence of the lower parasitic absorption together with uniform surface morphology can help photovoltaic performance maintain above 15%, which is beyond the performance of the pristine ZnO-based device achieving only 11.9%. Such superiority of ZnO:Zr ETL is also validated by a series of well-known BHJ systems, where in comparison with the devices based on pristine ZnO ETL, a better photovoltaic performance from ZnO:Zr device can be achieved.

14.
Eur J Nutr ; 60(4): 2217-2230, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33104864

RESUMO

PURPOSE: Inulin is a type of fermentable dietary fiber, which is non-digestible, and can improve metabolic function by modulating intestinal microbiota. This study aimed to evaluate the role of inulin in hyperuricemia and microbial composition of the gut microbiota in a mouse model of hyperuricemia established through knockout of Uox (urate oxidase) gene. METHODS: KO (Uox-knockout) and WT (wild-type) mice were given inulin or saline by gavage for 7 weeks. The effect of inulin to combat hyperuricemia was determined by assessing the changes in serum UA (uric acid) levels, inflammatory parameters, epithelial barrier integrity, fecal microbiota alterations, and SCFA (short-chain fatty acid) concentrations in KO mice. RESULTS: Inulin supplementation can effectively alleviate hyperuricemia, increase the expressions of ABCG2 in intestine, and downregulate expression and activity of hepatic XOD (xanthine oxidase) in KO mice. It was revealed that the levels of inflammatory cytokines and the LPS (lipopolysaccharide) were remarkably higher in the KO group than those in the WT group, indicating systemic inflammation of hyperuricemic mice, but inulin treatment ameliorated inflammation in KO mice. Besides, inulin treatment repaired the intestinal epithelial barrier as evidenced by increased levels of intestinal TJ (tight junction) proteins [ZO-1 (zonula occludens-1) and occluding] in KO mice. Moreover, serum levels of uremic toxins, including IS (indoxyl sulfate) and PCS (p-cresol sulfate), were reduced in inulin-treated KO mice. Further investigation unveiled that inulin supplementation enhanced microbial diversity and raised the relative abundance of beneficial bacteria, involving SCFAs-producing bacteria (e.g., Akkermansia and Ruminococcus). Additionally, inulin treatment increased the production of gut microbiota-derived SCFAs (acetate, propionate and butyrate concentrations) in KO mice, which was positively correlated with the effectiveness of hyperuricemia relief. CONCLUSIONS: Our findings showed that inulin may be a promising therapeutic candidate for the treatment of hyperuricemia. Moreover, alleviation of hyperuricemia by inulin supplementation was, at least, partially conciliated by modulation of gut microbiota and its metabolites.


Assuntos
Microbioma Gastrointestinal , Hiperuricemia , Animais , Suplementos Nutricionais , Hiperuricemia/tratamento farmacológico , Inulina , Camundongos , Camundongos Knockout
15.
J Appl Clin Med Phys ; 21(11): 88-97, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33016622

RESUMO

PURPOSE: To present the development of an in-house coded solution for treatment planning of tangential breast radiotherapy that creates single click plans by emulating the iterative optimization process of human dosimetrists. METHOD: One hundred clinical breast cancer patients were retrospectively planned with an automated planning (AP) code incorporating the hybrid intensity-modulated radiotherapy (IMRT) approach. The code automates all planning processes including plan generation, beam generation, gantry and collimator angle determination, open segments and dynamic IMRT fluence and calculations. Thirty-nine dose volume histogram (DVH) metrics taken from three international recommendations were compared between the automated and clinical plans (CP), along with median interquartile analysis of the DVH distributions. Total planning time and delivery QA were also compared between the plan sets. RESULTS: Of the 39 planning metrics analyzed 23 showed no significant difference between clinical and automated planning techniques. Of the 16 metrics with statistically significant variations, 2 were improved in the clinical plans in comparison to 14 improved in the AP plans. Automated plans produced a greater number of ideal plans against international guidelines as per EviQ (AP:77%, CP:68%), RTOG 1005 (AP:80%, CP:71%), and London Cancer references (AP:80%, CP:75%). Delivery QA results for both techniques were equivalent. Automated planning techniques resulted in an average reduction in planning time from 23 to 5 minutes. CONCLUSION: We have introduced an automated planning code with iterative optimization that produces equivalent quality plans to manual clinical planning. The resultant change in workflow results in a reduction in treatment planning times.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Feminino , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
16.
J Appl Clin Med Phys ; 21(12): 27-42, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33068070

RESUMO

Varian (Palo Alto, California, United States) recently released an online adaptation treatment platform, Ethos, which has introduced a new Dose Preview and Automated Plan Generation module despite sharing identical beam data with the existing Halcyon linac. The module incorporates a preconfigured beam model and the Acuros XB algorithm (Ethos AXB model) to generate final dose calculations from an initial fluence optimization. In this study, we comprehensively validated the accuracy of the Ethos AXB model by comparing it against the Halcyon AXB model, the Halcyon Anisotropic Analytical Algorithm (AAA) model, and measurements acquired on an Ethos linac. Results indicated that the Ethos AXB model demonstrated a comparable if not superior dosimetric accuracy to the Halcyon AXB model in basic and complex calculations, and at the same time its dosimetric accuracy in modulated and heterogeneous plans was better than that of the Halcyon AAA model. Despite the fact that the same algorithm was utilized, the Ethos AXB model and the Halcyon AXB model still exhibited variations across a range of tests, although these variations were predominantly insignificant in the clinical environment. The accuracy of the Ethos AXB model has been successfully verified in this study and is considered appropriate for the current clinical scope. On the basis of this study, clinical physicists can perform a data validation instead of a full data commissioning when implementing the Ethos system, thereby adopting a more efficient approach for Ethos installation.


Assuntos
Radiometria , Planejamento da Radioterapia Assistida por Computador , Algoritmos , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica
17.
Crit Rev Eukaryot Gene Expr ; 29(5): 437-448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32422000

RESUMO

Hyperlipidemia casts great threats to humans around the world. The systemic co-expression and function enrichment analysis for this disease is limited to date. This study was to identify co-expression modules to explore hyperlipidemia-associated functional pathways. Gene expression data of human hyperlipidemia (GSE17170) were downloaded from the Gene Expression Omnibus (GEO) database. We evaluated the top 3,000 genes with the highest average expression, with which the co-expression modules were constructed in weighted correlation network analysis (WGC-NA).Cluster analysis was then applied to visualize the interaction relationships of these modules. By gene ontology (GO) and KEGG functional enrichment analysis, we finally investigated the function enrichment of co-expression genes from important modules in the Database for Annotation, Visualization, and Integrated Discovery (DAVID) database (https:// david.ncifcrf.gov/summary.jsp).15 Thirteen co-expression modules were constructed for 3,000 genes in the 70samples. Interaction relationships of hub genes between pairwise modules showed high confidence. In functional enrichments of the co-expression modules, genes in Modules 3 and 4 were significantly enriched in biological processes and pathways that are associated with ubiquitination-for example, G0:0016567 (protein ubiquitination) and hsa04120 (ubiquitin-mediated proteolysis). We inferred these two modules as key modules associated with hyperlipidemia. Additionally, G0:0098609 (cell-cell adhesion) was enriched in four modules, suggesting an important function in hyperlipidemia. In conclusion, Protein ubiquitination may play important roles in human hyperlipidemia. All the discoveries made in this study enrich understanding of the pathogenesis of hyperlipidemia and might contribute much to the development of diagnosis and outcome evaluation of this disease.


Assuntos
Bases de Dados Factuais , Ontologia Genética , Redes Reguladoras de Genes/genética , Hiperlipidemias/genética , Ubiquitinação/genética , Análise por Conglomerados , Humanos
18.
Int Wound J ; 16(6): 1506-1512, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31531950

RESUMO

Breast cancer is a serious disease in women. We estimated the global technical success rate and complication rates of percutaneous vacuum-assisted breast biopsy (VABB). PubMed, Embase, Web of Science, and Scopus databases were retrieved up to July 2018 to find studies in which technical success rate and complication rates of VABB were available. Pooled rates were calculated according to location mode (ultrasonography [US] or mammography) and needle type (8- or 11-gauge Mammotome probes). Of the 36 articles with 20 868 cases, we found the pooled technical success rate 0.9999(0.9997, 1.0000) (I2 = 17.1%, P = .187) and low complication risks including haematoma 0.1092(0.0748, 0.1437) (I2 = 98.3%, P < .001), pain 0.0738(0.0334, 0.1141) (I2 = 95.9%, P < .001), vasovagal reflex 0.0281(0.0035, 0.0527) (I2 = 92.5%, P < .001), and infection 0.0027(-0.0019, 0.0073) (I2 = 49.8%, P = .113). In this systematic review and meta-analysis, the pooled data suggested that VABB with US or mammography could be promising for diagnosis and treatment of breast disease. Further studies were necessary to identify strategies for these findings.


Assuntos
Mama/patologia , Biópsia Guiada por Imagem/métodos , Vácuo , Feminino , Humanos
19.
Entropy (Basel) ; 21(1)2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33266780

RESUMO

Wave height and wave period are important oceanic environmental factors that are used to describe the randomness of a wave. Within the field of ocean engineering, the calculation of design wave height is of great significance. In this paper, a periodic maximum entropy distribution function with four undetermined parameters is derived by means of coordinate transformation and solving conditional variational problems. A double entropy joint distribution function of wave height and wave period is also derived. The function is derived from the maximum entropy wave height function and the maximum entropy periodic function, with the help of structures of the Copula function. The double entropy joint distribution function of wave height and wave period is not limited by weak nonlinearity, nor by normal stochastic process and narrow spectrum. Besides, it can fit the observed data more carefully and be more widely applicable to nonlinear waves in various cases, owing to the many undetermined parameters it contains. The engineering cases show that the recurrence level derived from the double entropy joint distribution function is higher than that from the extreme value distribution using the single variables of wave height or wave period. It is also higher than that from the traditional joint distribution function of wave height and wave period.

20.
J Biol Chem ; 290(9): 5414-23, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25583990

RESUMO

SET and MYND domain-containing 2 (Smyd2), a histone 3 lysine 4- and histone 3 lysine 36 (H3K36)-specific methyltransferase, plays critical roles in cardiac development and tumorigenesis. However, the role of Smyd2 in immunity and inflammation remains poorly understood. In this study, we report that Smyd2 is a novel negative regulator for macrophage activation and M1 polarization. Elevated Smyd2 expression suppresses the production of proinflammatory cytokines, including IL-6 and TNF, and inhibits the expression of important cell surface molecules, including major MHC-II and costimulatory molecules. Furthermore, macrophages with high Smyd2 expression inhibit Th-17 cell differentiation but promote regulatory T cell differentiation as a result of increased TGF-ß production and decreased IL-6 secretion. In macrophages, Smyd2 specifically facilitates H3K36 dimethylation at Tnf and Il6 promoters to suppress their transcription and inhibits NF-κB and ERK signaling. Therefore, our data demonstrate that epigenetic modification by Smyd2-mediated H3K36 dimethylation at Tnf and Il6 promoters plays an important role in the regulation of macrophage activation during inflammation.


Assuntos
Regulação da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Interleucina-6/genética , Macrófagos/metabolismo , Fator de Necrose Tumoral alfa/genética , Animais , Western Blotting , Diferenciação Celular/genética , Linhagem Celular , Células Cultivadas , Citometria de Fluxo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Interleucina-6/metabolismo , Lisina/metabolismo , Sistema de Sinalização das MAP Quinases , Ativação de Macrófagos/genética , Macrófagos/citologia , Metilação , Camundongos Endogâmicos C57BL , Mutação , NF-kappa B/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T Reguladores/metabolismo , Células Th17/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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