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BACKGROUND: This study aimed to explore the association between ideal cardiovascular health metrics (ICVHM) and arthritis (AR), as well as the interactions of various indicators in ICVHM on AR in US adults. METHODS: We involved 17,041 participants who were interviewed by NHANES from 2011 to 2018. AR included osteoarthritis or degenerative arthritis (OA), rheumatoid arthritis (RA), and psoriatic arthritis and other arthritis (Other AR). Logistic regression was applied to analyze the association between AR and ICVHM. Mixed graphical model (MGM) was used to explore the interaction between variables in ICVHM. RESULTS: Higher ICVHM scores had a protective effect on AR. Compared to "≤1" score, the ORs of AR in participants with 2, 3, 4, and ≥5 were 0.586, 0.472, 0.259, and 0.130, respectively. Similar results were also found in different types of AR. ICVHM has a maximum area under the curve value of 0.765 and the interaction between blood pressure and total cholesterol was 0.43. CONCLUSIONS: ICVHM correlates significantly with AR and is better at identifying AR than individual indicators. ICVHM can be better improved by controlling the indicators with stronger interactions. Our findings provide guidance for promoting health factors, which have important implications for identification and prevention of AR.
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Artrite , Sistema Cardiovascular , Adulto , Humanos , Inquéritos Nutricionais , Indicadores de Qualidade em Assistência à Saúde , Pressão SanguíneaRESUMO
Enantioselective total syntheses of pseudopteroxazole (1) and ileabethoxazole (2) are presented. The two original stereocenters were constructed in excellent enantioselectivity and good diastereoselectivity through Carreira's asymmetric dual catalytic allylation, which shows potential for accessing diastereoisomers at C2 and C3 of 1 and 2. Cationic cyclizations of 13 and 24 demonstrated an effective pathway for the construction of the opposite configurations at C1 in 1 and 2. Additionally, an approach for the introduction of methyl at C4 is a feasible solution for structural modifications at C4 in 1 and 2.
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By functionalization of the achiral carboxylate-based pyridine-N ligand 2,2'-bipyridine-3,3'-dicarboxylate (H2bpda) with N-oxide groups, the axially chiral ligand 2,2'-bipyridine-3,3'-dicarboxylate 1,1'-dioxide (H2bpdado) has been obtained. On the basis of H2bpdado and auxiliary N-donor ligands, two isostructural 3D dynamic porous Cu(II) metal-organic frameworks (MOFs), {[Cu0.5(bpdado)0.5(L)0.5]·3H2O}n (L = 1,2-bis(4-pyridyl)ethane (bpa), trans-1,2-bis(4-pyridyl)ethene (bpe) for 1 and 2, respectively), have been synthesized, which contain N-oxide "open donor sites" (ODSs) and carboxyl sites on the pore surfaces. The modification of pyridine-N into the N-oxide group not only transforms the nonporous structure into a porous framework but also endows the N-oxide group with unique charge-separated plus electron-rich character, which may provide an enhanced affinity toward CO2 molecules. Interestingly, both 1 and 2 present reversible structural transformation upon dehydration and rehydration. The adsorption properties of 1 and 2 have been investigated by N2, H2, CH4, and CO2 gases, and they reveal evident adsorption for CO2 and CH4. Both MOFs have high CO2 uptake, CO2 sorption affinity, and sorption selectivities of CO2 over CH4 and N2. Remarkably, 1' and 2' exhibit intriguingly comparable temperature-dependent CO2 sorption behaviors that can probably be attributed to the difference in bpa and bpe. First, at 195 K, 1' and 2' exhibit stepwise adsorption and hysteretic desorption behavior for CO2, but in the second step, the isotherms of 2' display a starting pressure greater than that of 1'. Then, at 298 K, their CO2 isotherms all show nonclassical type I adsorption, while peculiarly, at 273 K, the CO2 isotherm of 1' still exhibits uncommon stepwise adsorption but that of 2' does not. Thus, these temperature-dependent CO2 sorption behaviors indicate that there exist different threshold temperatures and pressures of channel expansion for 1' and 2'.
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Electrostatic generators show great potential for powering widely distributed electronic devices in Internet of Things (IoT) applications. However, a critical issue limiting such generators is their high impedance mismatch when coupled to electronics, which results in very low energy utilization efficiency. Here, we present a high-performance energy management unit (EMU) based on a spark-switch tube and a buck converter with an RF inductor. By optimizing the elements and parameters of the EMU, a maximum direct current output power of 79.2 mW m-2 rps-1 was reached for a rotary electret generator with the EMU, achieving 1.2 times greater power output than without the EMU. Furthermore, the maximum power of the contact-separated triboelectric nanogenerator with an EMU is 1.5 times that without the EMU. This excellent performance is attributed to the various optimizations, including utilizing an ultralow-loss spark-switch tube with a proper breakdown voltage, adding a matched input capacitor to enhance available charge, and incorporating an RF inductor to facilitate the high-speed energy transfer process. Based on this extremely efficient EMU, a compact self-powered wireless temperature sensor node was demonstrated to acquire and transmit data every 3.5 s under a slight wind speed of 0.5 m/s. This work greatly promotes the utilization of electrostatic nanogenerators in practical applications, particularly in IoT nodes.
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BACKGROUND: The association between macronutrient intake and diabetes is unclear. We used data from the China Health and Nutrition Survey to explore the association between macronutrient intake trajectories and diabetes risk in this study. METHODS: We included 6755 participants who did not have diabetes at baseline and participated in at least three surveys. The energy supply ratio of carbohydrate, protein, and fat was further calculated from dietary data; different macronutrient trajectories were determined using multitrajectory models; and multiple Cox regression models were used to evaluate the association between these trajectories and diabetes. RESULTS: We found three multitrajectories: decreased low carbohydrate-increased moderate protein-increased high fat (DLC-IMP-IHF), decreased high carbohydrate-moderate protein-increased low fat (DHC-MP-ILF), and balanced-macronutrients (BM). Compared to the BM trajectory, DHC-MP-ILF trajectories were significantly associated with increased risk of diabetes (hazard ratio [HR]: 3.228, 95% confidence interval [CI]: 1.571-6.632), whereas no association between DLC-IMP-IHF trajectories and diabetes was found in our study (HR: 0.699, 95% CI: 0.351-1.392). CONCLUSIONS: The downward trend of high carbohydrate and the increasing trend of low fat increased the risk of diabetes in Chinese adults.
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Carboidratos da Dieta , Nutrientes , Humanos , Feminino , Masculino , China/epidemiologia , Pessoa de Meia-Idade , Adulto , Nutrientes/análise , Carboidratos da Dieta/efeitos adversos , Carboidratos da Dieta/administração & dosagem , Fatores de Risco , Inquéritos Nutricionais , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/administração & dosagem , Diabetes Mellitus/epidemiologia , Ingestão de Energia , Proteínas Alimentares/administração & dosagem , Dieta/efeitos adversos , Dieta/estatística & dados numéricos , População do Leste AsiáticoRESUMO
BACKGROUND: Depression is a significant, pervasive, global public health problem, associated with many factors, such as diet, social factors, and lifestyle habits. We aimed to evaluate the association between eating breakfast, dietary inflammatory index (DII) and depression, and to verify the mediating role of DII on the effect of eating breakfast on depression. METHODS: 21,865 participants from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018 were included in this study. Binary logistic regression and mediated effect analysis were conducted to analyze the associations between eating breakfast, DII and depression. Dietary inflammation was divided into pro-inflammatory diet and anti-inflammatory diet according to the DII. RESULTS: Both pro-inflammatory diet and skipping breakfast were risk factors for depression. After adjusting for covariables, compared with participants reporting breakfast in both recalls, reporting breakfast in one recall had a higher OR 95%CI (1.54(1.20, 1.98)) of depression. These associations in stratified analysis and sensitivity analysis without cardiovascular diseases (CVD) and diabetes were robust. DII mediated the association between eating breakfast and depression, the proportion of participants who reported breakfast in one recall and no recall was 26.15 % and 26.67 %, respectively. LIMITATIONS: This was a cross-sectional study that couldn't argue for the cause-effect relationship. Moreover, the confounding factor regarding medication use was not accounted for due to limited data. CONCLUSIONS: Skipping breakfast may increase the risk of depression by raising DII. And our study supported the essential role of regular breakfast and the anti-inflammatory diet in reducing the risk of depression.
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Desjejum , Depressão , Humanos , Inquéritos Nutricionais , Depressão/epidemiologia , Depressão/etiologia , Estudos Transversais , Dieta/efeitos adversos , Inflamação/epidemiologia , Anti-InflamatóriosRESUMO
Background: Frailty has been one of the most serious global public health challenges we will ever face. Oxidative stress is associated with the pathogenesis of frailty, and may be accurately reflected by the oxidative balance score (OBS). However, there have been no studies examining the effect of OBS on frailty. Therefore, we aimed to explore the association between OBS and frailty and whether there was an interaction between the outcomes. Methods: 22 914 participants aged over 20 years taking part in the National Health and Nutrition Examination Survey (NHANES) in 2007-2018 were involved in the study. Sixteen dietary factors and four lifestyle factors were selected to score the OBS. A modified 36-item deficit cumulative frailty index (FI) was used to assess the degree of frailty. The association between OBS and frailty was analyzed using binary logistic regression. Subgroup analysis and interaction tests were used to investigate whether this association was stable across populations. Results: A negative association between OBS and the prevalence of frailty was found in this study. There was also an interaction between OBS and age in their association with frailty. High OBS was significantly and negatively associated with the prevalence of frailty in the 20-39 and 40-64 age groups. In addition, higher OBS combined with a population in the 20-39 age group resulted in a stronger negative association with frailty. Conclusion: High OBS was significantly associated with lower odds of frailty. An interaction existed between OBS and age. Individuals, especially in relatively young populations, are advised to increase OBS through greater intake of antioxidant nutrients and healthier lifestyles, thereby reducing the adverse effects of frailty.
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Fragilidade , Inquéritos Nutricionais , Estresse Oxidativo , Humanos , Fragilidade/epidemiologia , Pessoa de Meia-Idade , Feminino , Masculino , Adulto , Idoso , Adulto Jovem , Estudos Transversais , Estilo de Vida , Idoso de 80 Anos ou mais , PrevalênciaRESUMO
BACKGROUND: The global aging situation has reached a serious stage, and healthy lifestyles, like regular physical activity and eating breakfast, could slow the process. Phenotypic age (PhenoAge) is regarded as a novel measure of aging. Therefore, our study aimed to quantify the impact of physical activity and eating breakfast on aging via PhenoAge and phenotypic age acceleration (PhenoAgeAccel). METHODS: A total of 3719 adults who participated in the National Health and Nutrition Examination Survey were involved in this study. Physical activity was divided into an active group and an inactive group. According to the number of reported breakfast recalls, eating breakfast was divided into the no recalls group, one recall group, and both recalls group. Sensitivity analysis was performed by stratified analysis. RESULTS: Active physical activity was a protective factor for PhenoAge and PhenoAgeAccel. Compared to the inactive group, the ß values of the active group were -8.36 (-10.09, -6.62) for PhenoAge and -1.67 (-2.21, -1.14) for PhenoAgeAccel. The stratified analysis results showed that in the groups reporting breakfast in both recalls, one recall, and no recalls, the ß values of the active group were -8.84 (-10.70, -6.98), -8.17 (-12.34, -4.00), and -3.46 (-7.74, 0.82), respectively, compared to the inactive group. CONCLUSIONS: Active physical activity was strongly correlated with lower values of PhenoAge and PhenoAgeAccel, but the association was no longer statistically significant when combined with not regularly eating breakfast.
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Desjejum , Exercício Físico , Inquéritos Nutricionais , Rememoração Mental , Comportamento AlimentarRESUMO
Solar panels often suffer from dust accumulation, significantly reducing their output, especially in desert regions where many of the world's largest solar plants are located. Here, an autonomous dust removal system for solar panels, powered by a wind-driven rotary electret generator is proposed. The generator applies a high voltage between one solar panel's output electrode and an upper mesh electrode to generate a strong electrostatic field. It is discovered that dust particles on the insulative glass cover of the panel can be charged under the high electrical field, assisted by adsorbed water, even in low-humidity environments. The charged particles are subsequently repelled from the solar panel with the significant Coulomb force. Two panels covered with sand dust are cleaned in only 6.6 min by a 15 cm diameter rotary electret generator at 1.6 m s-1 wind speed. Experimental results manifest that the system can work effectively in a wide range of environmental conditions, and doesn't impact the panel performance for long-term operation. This autonomous system, with its high dust removal efficiency, simplicity, and low cost, holds great potential in practical applications.
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The global rise in prediabetes and diabetes, with type 2 diabetes (T2DM) being predominant, highlights the association between T2DM and hypertriglyceridemia (HTG). Patients with both abnormal glucose levels and HTG require increased attention due to higher risks of complications and mortality. Therefore, this study aimed to find the key long non-coding RNA (lncRNA) of HTG in the abnormal glucose metabolism patients. We collected blood samples for RNA sequencing experiments and blood samples for validation in population. We have conducted RNA sequencing, weighted gene co-expression network analysis (WGCNA), quantitative real-time polymerase chain reaction (qRT-PCR) in a 82-vs-82-sample-size population and insulin induced HepG2, RNA- Fluorescence in situ hybridization (FISH) and Cell Counting Kit-8 (CCK-8). We also explored lipid metabolism related transcription factor and the related protein expression and processed key lncRNA by both interference expression and overexpression, and the related consequences were rescued by its target mRNA. ENST00000540317.5 (LINC317.5) was lower in HTG with abnormal glucose metabolism and was found in both cytoplasm and nucleus in HepG2, inversely regulating the accumulation of TG and its target mRNA TKFC. Relative expression of peroxisome proliferator-activated receptor alpha (PPARα) and peroxisome proliferator-activated receptor gamma (PPARγ) were decreasing, and SREBP-1c (sterol regulatory element-binding protein-1c) was increasing of the interference expression of LINC317.5. Interference expression of LINC317.5 significantly decreased the protein expression of ACADM and CPT1A, whereas increased the protein expression of FAS and ACC1. TKFC partly reduced the triglyceride (TG) accumulation of LINC317.5. In conclusion, we suggested LINC317.5-TKFC as a key for TG accumulation in the HepG2-insulin resistant (IR). These might provide information of non-invasive biomarkers for the HTG with abnormal glucose.
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BACKGROUND: In the United States, the lifetime prevalence of depression in the US population is 20.6 %. We aimed to understand the temporal trends in the prevalence of depression among adults in the United States during the period 2013-2022 as well as the effects of age, period, and cohort effects on the prevalence of depression. METHODS: Data from 3,139,488 participants in the U.S. Behavioral Risk Factor Surveillance System (BRFSS) from 2013 to 2022 were used in this study. The joinpoint regression model was used to calculate annual percentage change (APC) and average annual percentage change (AAPC) to learn about the time trends in the prevalence of depression. Age-period-cohort models were used to estimate the effects of age, period, and birth cohort effects on the prevalence of depression. RESULTS: The prevalence of depression among adults in the United States showed an overall increasing trend from 2013 to 2022. The rate of increase was greater in males than females, with AAPC values of 1.44 % (95 % CI: 0.32-2.18), and 1.23 % (95 % CI: 0.32-2.25), respectively. Regarding the age effect, the risk of depression among adults in the United States generally showed an increasing and then decreasing trend with age. The risk of developing the condition reached its maximum at 50-54 years (RR = 1.28, 95 % CI = 1.26-1.30). Regarding the period effect, the risk of depression among US adults was higher during 2018-2022 than during 2013-2017. The overall cohort effect for depression prevalence was a higher risk for those born later, with a maximum RR of 1.51 (95 % CI: 1.47-1.54). CONCLUSION: The prevalence of adult depression in the United States is showing an increasing trend. Middle-aged people and those born later in life deserve more attention as high-risk groups. It is recommended that the condition burden of depression be reduced with the promotion of healthy lifestyles, the promotion of interpersonal communication, as well as enhanced mental health education and mental health literacy.
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Depressão , Humanos , Estados Unidos/epidemiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Prevalência , Depressão/epidemiologia , Idoso , Estudos de Coortes , Adulto Jovem , Sistema de Vigilância de Fator de Risco Comportamental , Fatores Etários , Adolescente , Fatores de Risco , Fatores SexuaisRESUMO
Background: Thyroid autoimmunity is an immune response to thyroid antigens that causes varying degrees of thyroid dysfunction. The sole effective treatment for Celiac Disease (CD) is a gluten-free diet (GFD). However, the association between GFD and thyroid autoimmunity in patients with CD has not been confirmed. Methods: A comprehensive search of several databases, involving PubMed, Embase, Web of Science, Medline, and Cochrane databases, was conducted to identify studies that primarily addressed the effects of GFD on thyroid autoimmunity in CD subjects. The meta-analysis involved studies that compared the risk of ATPO and ATG antibody positivity in CD patients with GFD, the risk of developing AITD, and the risk of developing thyroid dysfunction. Fixed-effects models or random-effects models were used to calculate the odds ratios (ORs) and their 95% confidence intervals (95% CIs). Results: A total of 10 observational studies met the inclusion criteria and included 6423 subjects. The results indicated that GFD is positively associated with thyroid autoimmunity in the children subgroup of CD patients (OR = 1.61, 95%CI 1.06-2.43, P = 0.02). However, there was no significant difference in thyroid autoimmunity between the group adhering to GFD and the control group in the total CD population. Conclusion: The results seem to indicate that subjects with a more pronounced autoimmunity (such as to have an early onset of CD) appear to have a greater risk of thyroid autoimmunity.
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Doença Celíaca , Glândula Tireoide , Criança , Humanos , Dieta Livre de Glúten/métodos , Autoimunidade , Resultado do TratamentoRESUMO
Background: Dyslipidemia is one of the most common chronic diseases, and is associated with insulin resistance (IR) and inadequate vitamin K intake. We aimed to explore the association between IR, vitamin K intake, and dyslipidemia, and further to explore the mediating role of IR. Materials and methods: 12 860 participants from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018 were included in this study. Insulin resistance was determined by using the homeostatic model assessment for insulin resistance (HOMA-IR). Weighted multiple logistic regression and mediation analyses were conducted to analyze the associations between IR, vitamin K intake, and dyslipidemia. Results: We found that both vitamin K intake-met Dietary Reference Intake (DRI) and non-IR were protective factors of high triglycerides (with ORs (95% CI) of 0.71 (0.57, 0.87) and 0.36 (0.29, 0.45), respectively) and low high-density lipoprotein cholesterol (with ORs (95% CI) of 0.72 (0.62, 0.82) and 0.39 (0.34, 0.41), respectively). IR-related indicators (HOMA-IR and insulin) partly mediated these effects, and the proportion ranged from 16.36% to 18.52%. Conclusion: Vitamin K intake-met DRI and non-IR were associated with lower risk of dyslipidemia including high TG and low HDL-C. IR partly mediated the association of vitamin K intake with high TG and low HDL-C.
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Dislipidemias , Resistência à Insulina , Adulto , Humanos , Inquéritos Nutricionais , Insulina , Vitamina KRESUMO
Semiconductor lasers, characterized by their high efficiency, small size, low weight, rich wavelength options, and direct electrical drive, have found widespread application in many fields, including military defense, medical aesthetics, industrial processing, and aerospace. The mode characteristics of lasers directly affect their output performance, including output power, beam quality, and spectral linewidth. Therefore, semiconductor lasers with high output power and beam quality are at the forefront of international research in semiconductor laser science. The novel parity-time (PT) symmetry mode-control method provides the ability to selectively modulate longitudinal modes to improve the spectral characteristics of lasers. Recently, it has gathered much attention for transverse modulation, enabling the output of fundamental transverse modes and improving the beam quality of lasers. This study begins with the basic principles of PT symmetry and provides a detailed introduction to the technical solutions and recent developments in single-mode semiconductor lasers based on PT symmetry. We categorize the different modulation methods, analyze their structures, and highlight their performance characteristics. Finally, this paper summarizes the research progress in PT-symmetric lasers and provides prospects for future development.
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Background: Diet and body mass index (BMI) are widely recognized as being closely associated with aging. However, it remains unclear which dietary indices are associated with aging, and the extent to which BMI mediates the relationship between diet and aging. Therefore, this study investigates the mediating role of BMI in the association between various dietary indices and phenotypic age acceleration (PhenoAgeAccel). Methods: Data were sourced from the National Health and Nutrition Examination Survey (NHANES), using two 24 hour recall interviews to compute four dietary indices: the Dietary Inflammatory Index (DII), Healthy Eating Index-2020 (HEI-2020), Alternative Healthy Eating Index-2010 (AHEI-2010), and Composite Dietary Antioxidant Index (CDAI). Linear regression analyses and mediation analyses assessed the associations between dietary indices and PhenoAgeAccel and the mediating effects of BMI. Z-score transformations (zDII, zHEI-2020, zAHEI-2010, and zCDAI) were used to ensure comparability between different dietary indices. Results: After adjusting for covariates, the zHEI-2020, zAHEI-2010, and zCDAI were negatively associated with PhenoAgeAccel (P < 0.05), with ß values being -0.36, -0.40, and -0.41, respectively. The zDII was positively associated with PhenoAgeAccel (P < 0.001) with a ß value of 0.70. Mediation analyses suggested that BMI significantly mediated the relationships between these dietary indices and PhenoAgeAccel. The mediation proportions were 23.7% for zDII, 43.3% for zHEI-2020, 24.5% for zAHEI-2010, and 23.6% for zCDAI. Conclusions: This study indicates that all dietary indices and BMI were significantly associated with PhenoAgeAccel. In addition, BMI exhibited the highest mediation proportion in the relationship between HEI-2020 and PhenoAgeAccel.
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Índice de Massa Corporal , Dieta , Inquéritos Nutricionais , Humanos , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Envelhecimento , Idoso , Fenótipo , Dieta SaudávelRESUMO
In this work, we investigated the potential UV protection mechanism of the natural compounds hydroxy resveratrol and pterostilbene by combining theoretical calculations and femtosecond transient absorption spectra (FTAS). The UV absorption spectra showed that the two compounds exhibited strong absorption properties and high photostability. We found two molecules will reach the S1 state or an even higher excited state after UV exposure and molecules in S1 will cross a lower energy barrier to reach the conical intersection. The adiabatic trans-cis isomerization process happened and finally return to the ground. Meanwhile, FTAS clarified the time scale of trans-cis isomerization of two molecules was â¼ 10 ps, which also met the requirement of fast energy relaxation. This work also provides theoretical guidance for developing new sunscreen molecules from natural stilbene.
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Electrostatic generators as a kind of effective energy harvesters have attracted intensive attention. However, the output of the generators is highly dependent on the charge density. Here, we demonstrate an all-in-one rotary electrostatic nanogenerator based on the charge pumping and voltage multiplying strategy (CV-ESG), which achieves high output power in SF6 atmosphere. CV-ESG integrates a pumping electret generator, a main generator, and a voltage multiplying and stabilization circuit on a pair of rotator and stator. We analyze the breakdown effect and its influence on the insulating layer covered on the electrodes through experiments. The breakdown voltage is high in SF6 atmosphere, and the maximum average power of CV-ESG in SF6 is 37.29 mW at 750 rpm, which is 3.29 times that in air. There is no surface friction in CV-ESG, which avoids abrasion and reduces friction damping. And the pumping generator is integrated with the main generator, making CV-ESG compact and easy to assemble. This work provides the design strategy for a high-power rotary electrostatic generator with good performance.
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Straightforward access to [1,2]-annulated indoles, key substructures in natural products, is highly desirable yet challenging. Herein, a radical triggered fragmentary cyclization cascade reaction of ene-ynamides is presented, providing a rapid access into [1,2]-annulated indoles by an intermolecular radical addition, intramolecular cyclization, desulfonylative aryl migration, and site-selective C(sp2)-N cyclization sequence. DFT calculations support oxidation of N-centered radical species to cations prior to the C-N bond formation, followed by an unusual aza-Nazarov cyclization.
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In this present work, we have successfully designed and investigated three flavonoid sunscreen compounds. Based on steady-state spectroscopy and time-dependent density functional theory (TDDFT), the mechanism of excited state intramolecular proton transfer (ESIPT) of sunscreen compounds was studied. The calculated UV-vis absorption spectra and fluorescence emission spectra are in good agreement with the experimental results in methanol solution. The potential energy curve demonstrates that the ESIPT process can easily occur in the three sunscreen compounds without energy barrier. Therefore, the absorbed excitation energy can get back to the ground state through a non-radiative relaxation process. Light stability tests ensure that the three flavonoids have the potential as sunscreens. This work provides not only an application of the ESIPT process in sunscreen mechanisms, but also a theory basis for the development of novel sunscreen molecules.
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Prótons , Protetores Solares , Modelos Moleculares , Teoria Quântica , Espectrometria de FluorescênciaRESUMO
Nowadays, traditional sunscreen molecules face many adverse problems: single energy relaxation pathway, lack of adequate UVA light protection, and therefore no longer meeting the growing demand for UVA protection. In this work, we reported a novel sunscreen molecule (E)-3-(5-bromofuran-2-yl)-1-(2-hydroxyphenyl)prop-2-en-1-one (hereinafter referred to as FPPO-HBr) which tackled adverse problems of traditional sunscreen molecules as single energy relaxation pathway, lacking effective UVA light protection. Various nonradiative pathways were proposed and verified by combining the steady-state and femtosecond transient absorption (FTA) spectroscopy and theoretical calculation. Upon UV excitation, the FPPO-HBr mainly decays via excited-state intramolecular proton transfer (ESIPT) followed by conformation twist in ultrafast manner. Importantly, 1H NMR spectra proved that the FPPO-HBr could not undergo trans-cis photoisomerization. Additionally, excellent photostability was also observed for newly synthesized FPPO-HBr. The current work could provide new perspectives for sunscreen molecules synthesis and mechanism.