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The introduction of axial-coordinated heteroatoms in FeâNâC single-atom catalysts enables the significant enhancement of their oxygen reduction reaction (ORR) performance. However, the interaction relationship between the axial-coordinated heteroatoms and their carbon supports is still unclear. In this work, a gas phase surface treatment method is proposed to prepare a series of XâFeâNâC (X = O, P, and S) single-atom catalysts with axial X-coordination on graphitic-N-rich carbon supports. Synchrotron-based X-ray absorption near-edge structure spectra and X-ray photoelectron spectroscopy indicate the formation of an axial charge transfer channel between the graphitic-N-rich carbon supports and single-atom Fe sites by axial O atoms in OâFeâNâC. As a result, the OâFeâNâC exhibits excellent ORR performance with a half-wave potential of 0.905 V versus RHE and a high specific capacity of 884 mAh g-1 for zinc-air battery, which is superior to other XâFeâNâC catalysts without axial charge transfer and the commercial Pt/C catalyst. This work not only demonstrates a general synthesis strategy for the preparation of single-atom catalysts with axial-coordinated heteroatoms, but also presents insights into the interaction between single-atom active sites and doped carbon supports.
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BACKGROUND: Numerous studies have documented significant alterations in the bodily fluids of Chronic Obstructive Pulmonary Disease (COPD) patients. However, existing literature lacks causal inference due to residual confounding and reverse causality. METHODS: Summary-level data for COPD were obtained from two national biobanks: the UK Biobank, comprising 1,605 cases and 461,328 controls, and FinnGen, with 6,915 cases and 186,723 controls. We also validated our findings using clinical data from 2,690 COPD patients and 3,357 healthy controls from the First Affiliated Hospital of Guangzhou Medical University. A total of 44 bodily fluid biomarkers were selected as candidate risk factors. Mendelian randomization (MR) and meta-analyses were used to evaluate the causal effects of these bodily fluids on COPD and lung function (FEV1/FVC). RESULTS: Mendelian randomization (MR) and meta-analyses, by integrating data from the UK Biobank and FinnGen cohort, found that 3 bodily fluids indicators (HDLC, EOS, and TP) were causally associated with the risk of COPD, two (EOS and TP) of which is consistent with our observational findings. Moreover, we noticed EOS and TP were causally associated with the risk of lung function (FEV1/FVC). CONCLUSIONS: The MR findings and clinical data highlight the independent and significant roles of EOS and TP in the development of COPD and lung function (FEV1/FVC), which might provide a deeper insight into COPD risk factors and supply potential preventative strategies.
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Líquidos Corporais , Doença Pulmonar Obstrutiva Crônica , Humanos , Pulmão , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Fatores de Risco , Estudo de Associação Genômica AmplaRESUMO
The topological phase transitions (TPT) of light refers to a topological evolution from one type of spin-orbit interaction to another, which has been recently found in beam scattering at optical interfaces and propagation in uniaxial crystals. In this work, the focusing of off-axis and partially masked circular-polarization Gaussian beams are investigated by using of a full-wave theory. Moreover, two different types of spin-orbit interactions (i.e., spin-dependent vortex generation and photonic spin-Hall effect) in the focusing system are unified from the perspective of TPT. It is demonstrated that as the off-axis distance or the masked area increases, a TPT phenomenon in the focused optical field takes place, evolving from the spin-dependent vortex generation to the spin-Hall shift of the beam centroids. The intrinsic mechanism is attributed to the cylindrical symmetry-breaking of the system. This symmetry-breaking induced TPT based on the method of vortex mode decomposition is further examined. The main difference between the TPT phenomenon observed here and that trigged by oblique incidence at optical interfaces or oblique propagation in uniaxial crystals is also uncovered. Our findings provide fruitful insights for understanding the spin-orbit interactions in optics, providing an opportunity for unifying the TPT phenomena in various spin-orbit photonics systems.
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We employ a full-wave theory to systematically investigate two types of spin-orbit interactions and their topological phase transitions for various light beams (e.g., Laguerre-Gaussian, Bessel, and Bessel-Gaussian beams) at optical interfaces, and explore the influence of beam parameters on the spin-Hall shift. It is demonstrated that at small-angle incidence, the beam profile and spin-Hall shift are significantly affected by the beam parameters (e.g., waist radius, radial index, azimuthal index, and cone angle), whereas at large-angle incidence, only the azimuthal index has a salient influence on them. We further find that the Bessel beam and the Gaussian-modulated ones (i.e., Laguerre-Gaussian and Bessel-Gaussian beams) have similar topological phase transition phenomena but different shifts. Quantitative dependences of beam parameters, such as waist radius, radial index, azimuthal index, and cone angle, on the shift are also presented. Our findings offer alternative degrees of freedom in controlling the topological phase transitions of light, and suggest a valuable insight for exploring the applications of SOIs of diverse light fields.
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Lipoxins (LXs) have attracted widespread attention as a class of anti-inflammatory lipid mediators that are produced endogenously by the organism. LXs are arachidonic acid (ARA) derivatives that include four different structures: lipoxin A4 (LXA4), lipoxin B4 (LXB4), and the aspirin-induced differential isomers 15-epi-LXA4 and 15-epi-LXB4. Because of their unique biological activity of reducing inflammation in the body, LXs have great potential for neuroprotection, anti-inflammatory treatment of COVID-19, and other related diseases. The synthesis of LXs in vivo is achieved through the action of lipoxygenase (LO). As a kind of important enzyme, LO plays a major role in the physiological processes of living organisms in mammals and functions in some bacteria and fungi. This suggests new options for the synthesis of LXs in vitro. Meanwhile, there are other chemical and biochemical methods to synthesize LXs. In this review, the recent progress on physiological activity and synthetic pathways of LXs is summarized, and new insights into the synthesis of LXs in vitro are provided.
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COVID-19 , Lipoxinas , Animais , Lipoxinas/farmacologia , Anti-Inflamatórios/farmacologia , Aspirina , Inflamação/tratamento farmacológico , MamíferosRESUMO
Carbon aerogels were newly employed in adsorption for volatile organic compounds (VOCs) as an emerging material. In contrast, the microstructure and high carbon consumption are the primary factors restricting their application scenarios. Carbon nanotubes, recognized for their controllable cylindrical hollow structure and hydrophobic walls, generally possess higher adsorption capacities than typical carbon adsorbents. In this study, carbon nanotubes were grown on the surface of carbon aerogels using the chemical vapor deposition method by controlling different deposition conditions. The results showed that the modified samples displayed the maximum adsorption capacity of 145.0 mg/g and 178.3 mg/g for toluene and 1,2- dichlorobenzene, respectively. After ten regeneration cycles, the performance decreased by 7.9 % and 5.6 %, respectively. Meanwhile, the carbon replenishment was about 0.2 g/g, which is an excellent complement for carbon consumption. Various characterization patterns showed that deposition temperature was reflected in its deposition rate, deposition times influenced the formation of multi-walled carbon nanotubes, and deposition concentration affected the length of carbon nanotubes. This study offers valuable insight into the growth patterns of carbon nanotubes and the microscale regulation of carbon material surfaces, and this method is expected to be an effective means of carbon replenishment, carbon addition to carbon-poor materials, and enhancement of VOCs removal performance, and the growth mechanisms investigated are instructive for practical applications.
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The role of thermally generated 3-aminopropionamide as an intermediate in acrylamide formation in the Maillard reaction has been well established. Herein, the effect of epicatechin on the conversion of 3-aminopropionamide into acrylamide under oxidative conditions was investigated at 160-220 °C. Epicatechin promoted acrylamide generation and 3-aminopropionamide degradation. The stable isotope-labeling technique combined with UHPLC-Orbitrap-MS/MS analysis showed adduct formation between 3-aminopropionamide and the oxidized B ring of epicatechin to form a Schiff base. This initially formed Schiff base could directly degrade to acrylamide, undergo reduction or dehydration to other intermediates, and subsequently generate acrylamide. Based on accurate mass analysis, five intermediates with intact or dehydrated C rings were tentatively identified. Furthermore, reaction pathways were proposed that were supported by the changes in the levels of adducts formed during heating. To the authors' knowledge, this study is the first to reveal pathways through which flavanols promoted the formation of acrylamide in Maillard reactions.
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Acrilamida , Catequina , Reação de Maillard , Oxirredução , Acrilamida/química , Catequina/química , Espectrometria de Massas em Tandem , Temperatura Alta , beta-Alanina/química , beta-Alanina/análogos & derivados , Bases de Schiff/química , Cromatografia Líquida de Alta PressãoRESUMO
When cells are stressed, DNA from energy-producing mitochondria can leak out and drive inflammatory immune responses if not cleared. Cells employ a quality control system called autophagy to specifically degrade damaged components. We discovered that mitochondrial transcription factor A (TFAM)-a protein that binds mitochondrial DNA (mtDNA)-helps to eliminate leaked mtDNA by interacting with the autophagy protein LC3 through an autolysosomal pathway (we term this nucleoid-phagy). TFAM contains a molecular zip code called the LC3 interacting region (LIR) motif that enables this binding. Although mutating TFAM's LIR motif did not affect its normal mitochondrial functions, more mtDNA accumulated in the cell cytoplasm, activating inflammatory signalling pathways. Thus, TFAM mediates autophagic removal of leaked mtDNA to restrict inflammation. Identifying this mechanism advances understanding of how cells exploit autophagy machinery to selectively target and degrade inflammatory mtDNA. These findings could inform research on diseases involving mitochondrial damage and inflammation.
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Autofagia , DNA Mitocondrial , Proteínas de Ligação a DNA , Inflamação , Mitocôndrias , Proteínas Mitocondriais , Fatores de Transcrição , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Inflamação/metabolismo , Inflamação/patologia , Inflamação/genética , Animais , Humanos , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Mitocôndrias/metabolismo , Mitocôndrias/genética , Camundongos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Ligação Proteica , Citoplasma/metabolismo , Lisossomos/metabolismo , Transdução de Sinais , Células HEK293 , Camundongos Endogâmicos C57BL , Proteínas de Grupo de Alta MobilidadeRESUMO
The problem of blood transshipment and allocation in the context of the COVID-19 epidemic has many new characteristics, such as two-stage, trans-regional, and multi-modal transportation. Considering these new characteristics, we propose a novel multi-objective optimization model for the two-stage emergent blood transshipment-allocation. The objectives considered are to optimize the quality of transshipped blood, the satisfaction of blood demand, and the overall cost including shortage penalty. An improved integer encoded hybrid multi-objective whale optimization algorithm (MOWOA) with greedy rules is then designed to solve the model. Numerical experiments demonstrate that our two-stage model is superior to one-stage optimization methods on all objectives. The degree of improvement ranges from 0.69 to 66.26%.
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The impact of Na2 CO3 on the properties of doughs and noodles containing 70% Tartary buckwheat flour was investigated. Low-field 1 H nuclear magnetic resonance showed the mobility of water in the doughs significantly declined with the addition content of alkali from 0% to 0.9%. Na2 CO3 promoted the transformation from free sulfhydryl groups to disulfide bonds in doughs because the sulfhydryl groups in cysteine preferred to form thiolate anion and then oxidate under alkaline conditions. As for non-covalent chemical interactions, a significant increase of hydrogen bonds and a decrease of hydrophobic interactions were observed after Na2 CO3 addition. Quantitative analysis of microstructure showed that more uniform and denser gluten networks with higher branching rate and shorter average protein length and width formed in the doughs with 0.3%-0.6% of Na2 CO3 . The aggregated glutenin macropolymer and enhanced protein structure led to significantly stronger tensile of Tartary buckwheat dough sheets, which could meet the demand of continuous processing in the factory. Dough with alkali had higher swelling power and pasting viscosities, contributing to higher water absorption, and improved textural attributes of cooked noodles. This study demonstrated the possibility of adding Na2 CO3 at a moderate level for promoting the sheeting, cooking, and eating properties of high Tartary buckwheat flour composite noodles.
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Fagopyrum , Farinha , Farinha/análise , Fagopyrum/química , Álcalis , ÁguaRESUMO
Interferon-induced transmembrane proteins (IFITMs) play an important role in the innate immune response triggered by viral infection. Transmissible gastroenteritis virus (TGEV) causes severe diarrhea, vomiting and dehydration in piglets, resulting in huge economic losses to the swine industry. In this study, we showed that IFITM3 inhibits the replication of TGEV and interferes with the binding of TGEV to PK15 cells. Moreover, the inhibitory effect of IFITM3 on TGEV circumvents the upregulation of inflammatory cytokines. Subsequently, we found that the M22A mutant loses part of the antiviral effect of IFITM3 on TGEV; in contrast, the K24A mutant enhances the antiviral effect of IFITM3. Notably, our data shows a synergistic effect between IFITM3 and CQ, which further amplifies the antiviral effect against TGEV.
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Gastroenterite Suína Transmissível , Doenças dos Suínos , Vírus da Gastroenterite Transmissível , Animais , Suínos , Vírus da Gastroenterite Transmissível/genética , Interferons , Antivirais , Imunidade InataRESUMO
Research has shown that the concentration and composition of biological samples may change after long-term ultra-low temperature storage. Consequently, this study examined the effect of ultra-low temperature storage on serum sIgE detection by comparing sIgE concentrations at various durations from the time of sample storage to subsequent testing. We selected 40 serum samples from the Guangzhou Medical University Affiliated First Hospital Biobank, which had been tested for house dust mites, dog hair, tobacco mold, cockroaches, and cow milk allergen sIgE. Samples were categorized by storage duration: 14 samples stored for 10 years, 12 for 5 years, and 14 for 3 years. They were also classified by sIgE positive levels: 15 samples at levels 1-2, 15 at levels 3-4, and 10 at levels 5-6. The allergen sIgE of these samples was retested using the same technology. Regardless of the type of allergen or the level of positivity, the majority of sIgE concentrations measured at the time of storage were higher than the current measurements, but the difference was not statistically significant. The correlation between the sIgE results at the time of storage and the current results was high for samples stored for 10 years (rs = 0.991, P < 0.001) and 5 years (rs = 0.964, P < 0.001). Serum allergen sIgE is stable when stored under ultra-low temperature conditions, making the construction of a biological sample bank for allergic diseases feasible. This will facilitate researchers in quickly obtaining samples, conducting technical research, and translating findings, thereby promoting the development of the field of allergy through integration of industry, academia, and research.
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Bancos de Espécimes Biológicos , Hipersensibilidade , Humanos , Feminino , Animais , Bovinos , Cães , Temperatura , Estudos de Viabilidade , Imunoglobulina E , Hipersensibilidade/diagnóstico , AlérgenosRESUMO
This study investigated the mechanism of delamination damage in the double cantilever beam (DCB) standard test by the use of the strain energy release rate. The curve of the strain energy release rate was verified by the Rise Angle (RA) method. For this purpose, 24-layer carbon fiber/epoxy multidirectional laminates with interface orientations of 0°, 30°, 45°, and 60° were fabricated according to the standard ASTM D5528(13). In the course of this test, acoustic emission (AE) was used for real-time monitoring, and combined with micro visualization, the damage mechanism of composite multidirectional laminates was studied at multiple scales. Combining the AE detection results with micro visualization, it is found that the AE parameters and the damage to multidirectional laminates could realize a one-to-one correspondence. Through the study of the variation of the RA value, load, and strain energy release rate with the crack length, it is proved that the AE parameters can effectively characterize the initiation of delamination damage.
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Whether HbA1c levels are associated with mortality in subjects without known diabetes remains controversial. Moreover, the shape of the dose-response relationship on this topic is unclear. Therefore, a dose-response meta-analysis was conducted. PubMed and EMBASE were searched. Summary hazard ratios (HRs) were calculated using a random-effects model. Twelve studies were included. The summary HR per 1% increase in HbA1c level was 1.03 [95% confidence interval (CI) = 1.01-1.04] for all-cause mortality, 1.05 [95% CI = 1.02-1.07) for cardiovascular disease (CVD) mortality, and 1.02 (95% CI = 0.99-1.07) for cancer mortality. After excluding subjects with undiagnosed diabetes, the aforementioned associations remained significant for CVD mortality only. After further excluding subjects with prediabetes, all aforementioned associations presented non-significance. Evidence of a non-linear association between HbA1c and mortality from all causes, CVD and cancer was found (all Pnon-linearity < 0.05). The dose-response curves were relatively flat for HbA1c less than around 5.7%, and rose steeply thereafter. In conclusion, higher HbA1c level is associated with increased mortality from all causes and CVD among subjects without known diabetes. However, this association is driven by those with undiagnosed diabetes or prediabetes. The results regarding cancer mortality should be treated with caution due to limited studies.
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Causas de Morte , Complicações do Diabetes/sangue , Diabetes Mellitus/sangue , Hemoglobinas Glicadas/metabolismo , Adulto , Idoso , Algoritmos , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Complicações do Diabetes/mortalidade , Diabetes Mellitus/mortalidade , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/genética , Neoplasias/mortalidade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/mortalidade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de Regressão , Fatores de RiscoRESUMO
BACKGROUND: A striking gender disparity in the incidence and outcome of primary liver cancer (PLC) has been well recognized. Mounting evidence from basic research suggests that hormonal factors may be involved in the gender disparity of PLC. Whether hormonal exposures in human subjects are associated with PLC risk is largely unknown. OBJECTIVE AND RATIONALE: Whether reproductive factors and use of menopausal hormone therapies (MHTs) in women are associated with PLC risk remains controversial. We conducted this study to clarify this issue. SEARCH METHODS: PubMed and EMBASE were searched to July, 2016 for studies published in English or Chinese. Observational studies (cohort, nested case-control and case-control) that provided risk estimates of reproductive factors, MHTs and PLC risk were eligible. The quality of included studies was determined based on the Newcastle-Ottawa quality assessment scale. Summary risk ratios (RRs) were calculated using a random-effects model. Dose-response analysis was conducted where possible. OUTCOMES: Fifteen peer-reviewed studies, involving 1795 PLC cases and 2 256 686 women, were included. Overall meta-analyses on parity and PLC risk did not find any significant associations; however, when restricting to studies with PLC cases ≥100, increasing parity was found to be significantly associated with a decreased risk of PLC [RR for the highest versus lowest parity 0.67, 95% CI 0.52, 0.88; RR for parous versus nulliparous 0.71, 95% CI 0.53, 0.94; RR per one live birth increase 0.93, 95% CI 0.88, 0.99]. A J-shaped relationship between parity and PLC risk was identified (Pnon-linearity < 0.01). Compared with never users, the pooled RRs of PLC were 0.60 (95% CI 0.37, 0.96) for ever users of MHT, 0.73 (95% CI 0.46, 1.17) for ever users of estrogen-only therapy (ET) and 0.67 (95% CI 0.45, 1.02) for ever users of estrogen-progestin therapy (EPT). The pooled RR of PLC for the oldest versus youngest category of menarcheal age was 0.50 (95% CI 0.32, 0.79). Oophorectomy was significantly associated with an increased risk of PLC (RR 2.23, 95% CI 1.46, 3.41). No significant association of age at first birth, and spontaneous or induced abortion with PLC risk was found. No meta-analysis was performed for the association of age at menopause, breastfeeding, hysterectomy, menopausal status and stillbirth with PLC risk owing to huge methodological heterogeneity and/or very limited studies. WIDER IMPLICATIONS: Parity is associated with PLC risk in a J-shaped dose-response pattern. Late age at menarche and ever use of MHT are associated with a reduced risk of PLC, whereas there is no association of ever use of ET and EPT, age at first birth, or spontaneous and induced abortion with PLC risk. Compared to women with no history of oophorectomy, those with a history of oophorectomy are at an increased risk of PLC. Our findings provide some epidemiological support for a role of hormonal exposures in the development of PLC in women. However, these findings should be interpreted with much caution because of the limited number of studies and potential biases, and need to be validated by studies with good design and large sample size.
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Estrogênios/efeitos adversos , Terapia de Reposição Hormonal/efeitos adversos , Neoplasias Hepáticas/induzido quimicamente , Progestinas/efeitos adversos , História Reprodutiva , Anticoncepcionais Orais/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Humanos , Incidência , Menarca , Estudos Observacionais como Assunto , Razão de Chances , Paridade , Gravidez , Fatores de Risco , Fatores SexuaisRESUMO
BACKGROUND: Whether ever use of oral contraceptives (OCs) is associated with mortality remains unclear. OBJECTIVES: To evaluate the association between ever use of OCs and mortality. SEARCH STRATEGY: On November 2, 2014, PubMed and Embase were searched for human studies, using the terms "contraceptive," "contraceptives," "death," and "mortality." SELECTION CRITERIA: Prospective cohort studies were included that provided risk estimates on OC use and mortality, and were reported in English or Chinese. DATA COLLECTION AND ANALYSIS: A random-effects model was used to pool data. Random-effects meta-regression was used to determine whether duration of OC use and time since last OC use were associated with mortality. MAIN RESULTS: Nine studies were included. Ever use of OCs was not associated with mortality from all causes (hazard ratio [HR] 0.94; 95% CI 0.87-1.02) or breast cancer (HR 1.00; 95% CI 0.95-1.06). Neither the duration of OC use nor the time since last OC use was associated with all-cause or breast cancer mortality. In an analysis of a small number of studies, ever users were at decreased risk of mortality from ovarian cancer (HR 0.58; 95% CI 0.35-0.94). CONCLUSIONS: There is no significant association between ever use of OCs and mortality from all causes or breast cancer.