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This study explores the association between LE8 scores and mortality risks among individuals diagnosed with cardiovascular disease (CVD). Utilizing data from the NHANES conducted between 2005 and 2018, survey-weighted multivariable Cox proportional hazards regression models were utilized. Life's Essential 8 (LE8) scores dose-response associations were assessed using restricted cubic spline regression. Sub-analyses were performed for different categories of CVD. The study consisted of 2164 participants diagnosed with CVD, ranging in age from 20 to 80 years (weighted mean [SE] age, 61.47 [0.34] years; The average total LE8 was 64.97 [0.54]. 499 participants experienced mortality, with 350 deaths attributed to CVD. After accounting for potential covariates, LE8 score was found to be associated with a decreased both all-cause mortality (OR 0.34, CI 0.22-0.51) and CVD mortality (OR 0.40, CI 0.23-0.68). A survey-weighted multivariable Cox model with restricted cubic splines identified the lowest all-cause mortality (P < 0.001) and CVD mortality (P < 0.001) risk when LE8 reach at 63.75 (P < 0.001). The results highlight the association between LE8 scores and reduced mortality in CVD patient population. The implementation of comprehensive initiatives that prioritize healthy dietary patterns, will play a crucial role in alleviating the impact of cardiovascular disease and improving cardiovascular health outcomes.
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Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/mortalidade , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Adulto , Idoso de 80 Anos ou mais , Modelos de Riscos Proporcionais , Adulto Jovem , Fatores de Risco , Inquéritos NutricionaisRESUMO
Anion photoelectron spectroscopy and theoretical calculations were used to investigate the structural and bonding properties of WN10-/0. The electron affinity of WN10 is measured to be 1.582 ± 0.030 eV. The frequency of the NîN stretch in WN10 is measured to be 2170 ± 80 cm-1, which is red-shifted with respect to that of the dinitrogen molecule indicating that the NîN bonds are weakened in WN10. The theoretical adiabatic detachment energy (ADE) and vertical detachment energy (VDE) of WN10- obtained by calculations at the CCSD(T)/CBS level agree well with experimental results. The structures of WN10-/0 are C4v symmetric pentacoordinated pyramidal structures with five end-on dinitrogen ligands. Our experiments show that the peak of WN10- is dominant in the mass spectrum of anionic WNn, whereas the mass peak of WN12+ is dominant in the mass spectrum of cationic WNn, implying that the stabilities of WNn clusters are strongly related to their charge states.
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The aim of this study were to estimate associations of sarcopenic status with depressive symptoms. We used mixed-effects linear model to estimate longitudinal association between sarcopenic status and rate of change in 10-item Center for Epidemiologic Studies Depression (CES-D) scores, and used Cox regression model to estimate the association between sarcopenic status and incident depression (CES-D ≥ 10). Stratification analyses were performed when the interactions between sarcopenic status and covariates were significant. A total of 6522 participants were ultimately included. After adjusting for covariates, participants with possible sarcopenia (ß = 0.117; 95% CI 0.067 to 0.166; P < 0.001) and sarcopenia (ß: 0.093; 95% CI 0.027-0.159; P < 0.001) had a faster increase in CES-D scores compared with normal individuals. Interactions between smoking and sarcopenic status were significant (Pinteraction < 0.05). We found significantly positive associations of sarcopenic status with CES-D scores in nonsmokers, but not in current and past smokers. Besides, compared with normal participants, those with possible sarcopenia (HR 1.15; 95% CI 1.05 to 1.27) and sarcopenia (HR 1.28; 95% CI 1.12 to 1.46) (Ptrend < 0.001) had elevated risks of incident depression. Sarcopenia is associated with a faster increase in CES-D scores and increased risks of depression among Chinese middle-aged and older adults. Stronger associations between sarcopenia and trajectory of CES-D scores were found in nonsmokers than in smokers.
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Depressão , Sarcopenia , Fumar , Humanos , Sarcopenia/epidemiologia , Masculino , Feminino , Depressão/epidemiologia , Pessoa de Meia-Idade , Idoso , Fumar/epidemiologia , Fatores de Risco , China/epidemiologiaRESUMO
OBJECTIVE: This study aimed to investigate the potential mediating role of the neurofilament light chain (NfL) level between depressive symptoms and cognitive function in older population. METHODS: A total of 495 adults (age ≥60 years) from the National Health and Nutrition Examination Survey (NHANES) participated in this study. Cognitive function was assessed using a combination of the Animal Fluency Test (AFT), the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) and the Digit Symbol Substitution Test (DSST). Word List Learning Test. Patient Health Questionnaire-9 (PHQ-9) was used to assess depressive symptoms. Data on serum NfL(sNfL) were collected. Multiple linear regressions and mediation analysis were utilized to examine the associations. RESULTS: After adjusting for potential confounding factors, the proportions mediated by the sNfL level between depressive symptoms and cognitive function was 19.65 %. The indirect effect mediated by the sNfL level between depressive symptoms and cognitive function was significant (ß[95 % CI]:-0.0089 [-0.0191, -0.0017],p = 0.040), while the direct effect in the absence of sNfL was non-significant (ß[95 % CI]: -0.0365 [-0.0739 0.0008],p = 0.055). LIMITATIONS: This is an explorative cross-sectional study with its limits in generalizability and ability to establish definitive causal associations. The results should be interpreted with caution due to the constraints imposed by the characteristics of the population with a relatively low overall level of depressive symptoms. CONCLUSION: The sNfL level, depressive symptoms, and cognitive decline are interconnected, and the sNfL level could mediate the relationship between depressive symptoms and cognitive decline among older adults.
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Cognição , Disfunção Cognitiva , Depressão , Proteínas de Neurofilamentos , Inquéritos Nutricionais , Humanos , Feminino , Masculino , Idoso , Depressão/epidemiologia , Proteínas de Neurofilamentos/sangue , Pessoa de Meia-Idade , Cognição/fisiologia , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/sangue , Estudos Transversais , Testes Neuropsicológicos/estatística & dados numéricos , Idoso de 80 Anos ou maisRESUMO
Background: Stroke, prevalent globally, particularly impacts low- and middle-income countries. Decreased lung function is one of the risk factors for stroke, and there is a lack of sufficient research on the association between the two, especially based on evidence from representative large samples. We aimed to explore the association between lung function and stroke incidence. Methods: We collected data from 13,371 participants from the 2007-2012 U.S. national cross-sectional study and 11,192 participants from the Chinese national cohort study during the 2011-2018 follow-up period. Multivariate logistic regression and Cox proportional hazards regression were used to assess cross-sectional and longitudinal associations of peak expiratory flow with stroke risks. Additionally, we used publicly available GWAS data from a European population to conduct Mendelian randomization analysis, further exploring the potential causal relationship. Results: The results of the cross-sectional study suggest that a decline in peak expiratory flow may be associated with an increased risk of stroke. The cohort study revealed that, compared to the first tertile group, the risk of stroke incidence in the second and third tertile groups of PEF decreased by 19% (hazard ratio (HR) = 0.810, 95%CI = 0.684-0.960) and 21.4% (HR = 0.786, 95%CI = 0.647-0.956), respectively. Mendelian randomization analysis clarified that higher PEF levels are significantly associated with a reduced risk of stroke (OR = 0.852, 95%CI = 0.727-0.997). Conclusion: Decreased lung function is a risk factor for stroke. As a simple and accurate indicator of lung function, PEF can be used to monitor lung function in community populations and patients for primary stroke prevention.
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The association between cooking fuel and hearing loss still needs more research to clarify, and two longitudinal cohort studies were explored to find if solid fuel use for cooking affected hearing in Chinese adults. The data from Chinese Health and Retirement Longitudinal Survey (CHARLS) and Chinese Longitudinal Healthy Longevity Survey (CLHLS) were analyzed. Participants (older than 18) without hearing loss at baseline and follow-up visits were included, which were divided into clean fuel and solid fuel groups. Hearing loss rate was from follow-up visits (both in year 2011) until the recent one (year 2018 in CHARLS and 2019 in CLHLS). Cox regressions were applied to examine the associations with adjustment for potential confounders. Fixed-effect meta-analysis was used to pool the results. A total of 9049 participants (average age 8.34 ± 9.12 [mean ± SD] years; 4247 [46.93%] males) were included in CHARLS cohort study and 2265 participants (average age, 78.75 ± 9.23 [mean ± SD] years; 1148 [49.32%] males) in CLHLS cohort study. There were 1518 (16.78%) participants in CHARLS cohort and 451 (19.91%) participants in CLHLS cohort who developed hearing loss. The group of using solid fuel for cooking had a higher risk of hearing loss (CHARLS: HR, 1.16; 95% CI 1.03-1.30; CLHLS: HR, 1.43; 95% CI 1.11-1.84) compared with the one of using clean fuel. Pooled hazard ratio showed the incidence of hearing loss in the solid fuel users was 1.17 (1.03, 1.29) times higher than that of clean fuel users. Hearing loss was associated with solid fuel use and older people were at higher risk. It is advised to replace solid fuel by clean fuel that may promote health equity.
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Culinária , Perda Auditiva , Humanos , Masculino , Perda Auditiva/epidemiologia , Perda Auditiva/etiologia , Perda Auditiva/induzido quimicamente , Feminino , Idoso , China/epidemiologia , Pessoa de Meia-Idade , Estudos Longitudinais , Estudos de Coortes , Idoso de 80 Anos ou mais , Adulto , Fatores de RiscoRESUMO
Bipyramidal structures featuring planar rings serve as potential building blocks for one-dimensional (1D) nanostructures. Pure Ge atoms typically prefer to form three-dimensional rather than planar structures. Although a few-metal-doped bipyramids with pure Ge planar rings are predicted for constructing Ge-based 1D nanostructures, there is limited knowledge about those with both Ge and doped atoms on the same planar rings. Here, we report a hexagonal bipyramidal Mn3Ge5 cluster containing a Mn3Ge3 six-membered ring with the potential to construct a 1D germanium-based nanostructure. We investigated the structures and properties of Mn3Ge5-/0 using anion photoelectron spectroscopy and theoretical calculations. Mn3Ge5- has a C3v symmetric distorted hexagonal bipyramidal structure, while Mn3Ge5 has a C2v symmetric hexagonal bipyramidal structure. Chemical bonding analyses show that Mn3Ge5- could be considered as a [Mn3]V[Ge5]6- complex. First-principles calculations indicate that Mn3Ge5 may be used to construct a 1D ferrimagnetic [Mn3Ge5]∞ nanostructure.
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BACKGROUND: With the development of pathophysiology, cardiorenal syndrome (CRS), a complex and severe disease, has received increasing attention. Monocyte to high-density lipoprotein-cholesterol ratio (MHR) and body mass index (BMI) are independent risk factors for cardiovascular diseases, but their association with CRS remains unexplored. This study aims to explore the independent and joint effects of MHR and BMI on CRS. METHODS: We included 42,178 NHANES participants. The determination of CRS referred to the simultaneous presence of cardiovascular disease (identified through self-report) and chronic kidney disease (eGFR < 60 mL/min per 1.73 m²). We employed multivariate weighted logistic regression to evaluate the odds ratio (OR) and 95% confidence interval (CI) for the independent and joint associations of MHR and BMI with CRS. We also conducted restricted cubic spines to explore nonlinear associations. RESULTS: The prevalence of CRS was 3.45% among all participants. An increase in both MHR and BMI is associated with a higher risk of CRS (MHR: OR = 1.799, 95% CI = 1.520-2.129, P < 0.001, P-trend < 0.001; BMI: OR = 1.037, 95% CI = 1.023-1.051, P < 0.001). Individuals who simultaneously fall into the highest quartile of MHR and have a BMI of 30 or more face the highest risk of CRS compared to those in the lowest MHR quartile with a BMI of less than 25 (OR = 3.45, 95% CI = 2.40-4.98, P < 0.001). However, there is no interactive association between MHR and BMI with CRS. CONCLUSIONS: Higher MHR and BMI are associated with higher odds of CRS. MHR and BMI can serve as tools for early prevention and intervention of CRS, respectively.
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Índice de Massa Corporal , Síndrome Cardiorrenal , HDL-Colesterol , Monócitos , Humanos , Masculino , Feminino , Monócitos/metabolismo , Pessoa de Meia-Idade , Síndrome Cardiorrenal/sangue , Síndrome Cardiorrenal/epidemiologia , HDL-Colesterol/sangue , Idoso , Fatores de Risco , Adulto , Inquéritos Nutricionais , Razão de Chances , Modelos LogísticosRESUMO
Stay-green (SG) in wheat is a beneficial trait that increases yield and stress tolerance. However, conventional phenotyping techniques limited the understanding of its genetic basis. Spectral indices (SIs) as non-destructive tools to evaluate crop temporal senescence provide an alternative strategy. Here, we applied SIs to monitor the senescence dynamics of 565 diverse wheat accessions from anthesis to maturation stages over 2 field seasons. Four SIs (normalized difference vegetation index, green normalized difference vegetation index, normalized difference red edge index, and optimized soil-adjusted vegetation index) were normalized to develop relative stay-green scores (RSGS) as the SG indicators. An RSGS-based genome-wide association study identified 47 high-confidence quantitative trait loci (QTL) harboring 3,079 single-nucleotide polymorphisms associated with SG and 1,085 corresponding candidate genes. Among them, 15 QTL overlapped or were adjacent to known SG-related QTL/genes, while the remaining QTL were novel. Notably, a set of favorable haplotypes of SG-related candidate genes such as TraesCS2A03G1081100, TracesCS6B03G0356400, and TracesCS2B03G1299500 are increasing following the Green Revolution, further validating the feasibility of the pipeline. This study provided a valuable reference for further quantitative SG and genetic research in diverse wheat panels.
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Sterols have long been associated with diverse fields, such as cancer treatment, drug development, and plant growth; however, their underlying mechanisms and functions remain enigmatic. Here, we unveil a critical role played by a GmNF-YC9-mediated CCAAT-box transcription complex in modulating the steroid metabolism pathway within soybeans. Specifically, this complex directly activates squalene monooxygenase (GmSQE1), which is a rate-limiting enzyme in steroid synthesis. Our findings demonstrate that overexpression of either GmNF-YC9 or GmSQE1 significantly enhances soybean stress tolerance, while the inhibition of SQE weakens this tolerance. Field experiments conducted over two seasons further reveal increased yields per plant in both GmNF-YC9 and GmSQE1 overexpressing plants under drought stress conditions. This enhanced stress tolerance is attributed to the reduction of abiotic stress-induced cell oxidative damage. Transcriptome and metabolome analyses shed light on the upregulation of multiple sterol compounds, including fucosterol and soyasaponin II, in GmNF-YC9 and GmSQE1 overexpressing soybean plants under stress conditions. Intriguingly, the application of soybean steroids, including fucosterol and soyasaponin II, significantly improves drought tolerance in soybean, wheat, foxtail millet, and maize. These findings underscore the pivotal role of soybean steroids in countering oxidative stress in plants and offer a new research strategy for enhancing crop stress tolerance and quality from gene regulation to chemical intervention.
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Glycine max , Estresse Fisiológico , Glycine max/genética , Glycine max/fisiologia , Glycine max/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Esteroides/metabolismo , Secas , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genéticaRESUMO
INTRODUCTION: With the growing emphasis on swift recovery, minimally invasive thoracic surgery has advanced significantly. Video-assisted thoracoscopic surgery (VATS) has seen rapid development, and the double-lumen tube (DLT) remains the most dependable method for tracheal intubation in VATS. However, hypoxaemia during DLT intubation poses a threat to the perioperative safety of thoracic surgery patients. Recently, transnasal high-flow nasal oxygen (HFNO) has shown promise in anaesthesia, particularly in handling short-duration hypoxic airway emergencies. Yet, its application in the perioperative period for patients undergoing pulmonary surgery with compromised cardiopulmonary function lacks evidence, and there are limited reliable clinical data. METHODS AND ANALYSIS: A prospective, randomised, controlled, single-blind design will be employed in this study. 112 patients aged 18-60 years undergoing elective VATS-assisted pulmonary surgery will be enrolled and randomly divided into two groups: the nasal high-flow oxygen group (H group) and the traditional mask transnasal oxygen group (M group) in a 1:1 ratio. HFNO will be used during DLT intubation for the prevention of asphyxia in group H, while conventional intubation procedures will be followed by group M. Comparison will be made between the two groups in terms of minimum oxygen saturation during intubation, hypoxaemia incidence during intubation, perioperative complications and postoperative hospital days. ETHICS AND DISSEMINATION: Approval for this study has been granted by the local ethics committee at Shenzhen Second People's Hospital. The trial results will be disseminated through peer-reviewed journals and scientific conferences. TRIAL REGISTRATION NUMBER: NCT05666908.
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Máscaras , Oxigênio , Humanos , Hipóxia/etiologia , Hipóxia/prevenção & controle , Intubação Intratraqueal , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-IdadeRESUMO
Stripe rust is a devastating disease of wheat worldwide. Chinese wheat cultivar Lanhangxuan 121 (LHX121), selected from an advanced line L92-47 population that had been subjected to space mutation breeding displayed a consistently higher level of resistance to stipe rust than its parent in multiple field environments. The aim of this research was to establish the number and types of resistance genes in parental lines L92-47 and LHX121 using separate segregating populations. The first population developed from a cross between LHX121 and susceptible cultivar Xinong 822 comprised 278 F2:3 lines. The second validation population comprised 301 F2:3 lines from a cross between L92-47 and susceptible cultivar Xinong 979. Lines of two population were evaluated for stripe rust response at three sites during the 2018-2020 cropping season. Affymetrix 660 K SNP arrays were used to genotype the lines and parents. Inclusive composite interval mapping detected QTL QYrLHX.nwafu-2BS, QYrLHX.nwafu-3BS, and QYrLHX.nwafu-5BS for resistance in all three environments. Based on previous studies and pedigree information, QYrLHX.nwafu-2BS and QYrLHX.nwafu-3BS were likely to be Yr27 and Yr30 that are present in the L92-47 parent. QYrLHX.nwafu-5BS (YrL121) detected only in LHX121 was mapped to a 7.60 cM interval and explained 10.67-22.57% of the phenotypic variation. Compared to stripe rust resistance genes previously mapped to chromosome 5B, YrL121 might be a new adult plant resistance QTL. Furthermore, there were a number of variations signals using 35 K SNP array and differentially expressed genes using RNA-seq between L92-47 and LHX121 in the YrL121 region, indicating that they probably impair the presence and/or function of YrL121. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01461-0.
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Particulate Matter 2.5 (PM2.5) is a significant risk factor for frailty and chronic diseases. Studies on the associations between PM2.5 and frailty, chronic diseases, and multimorbidity are scarce, especially from large cohort studies. We aimed to explore the potential association between PM2.5 exposure and the risk of frailty, chronic diseases, and multimorbidity. We collected data from a national cohort (CHARLS) with a follow-up period of 11-18 years, totaling 13,366 participants. We obtained PM2.5 concentration data from the Atmospheric Composition Analysis Group at Dalhousie University. PM2.5 exposure is based on the average annual concentration in the prefecture-level city where residents live. We define frailty as the comprehensive manifestation of declining various body functions, characterized by a frailty index of 0.25 or greater, and multimorbidity as the presence of at least two or more chronic conditions. Cox proportional hazards regression was used to estimate the hazard ratio (HR) with its 95% confidence interval (95%CI). A 10-µg/m3 increase for PM2.5 was significantly associated with an increased risk of frailty (HR = 1.289, 95%CI = 1.257-1.322, P < 0.001). A 10-µg/m3 increase for PM2.5 was significantly associated with the elevated risk for most chronic diseases. Compared to those with no morbidity or only single morbidity, a 10-µg/m3 increase for PM2.5 was significantly associated with the elevated risk for multimorbidity (HR = 1.220, 95%CI = 1.181-1.260, P < 0.001). Ambient PM2.5 exposure is a significant risk factor for frailty, chronic diseases, and multimorbidity, and some measures need to be taken to reduce PM2.5 concentration and prevent frailty and chronic diseases.
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Poluentes Atmosféricos , Poluição do Ar , Fragilidade , Pessoa de Meia-Idade , Humanos , Idoso , Poluentes Atmosféricos/análise , Fragilidade/epidemiologia , Fragilidade/induzido quimicamente , Estudos Longitudinais , Multimorbidade , Material Particulado/análise , Doença Crônica , Exposição Ambiental/análise , Poluição do Ar/análiseRESUMO
Ferromagnets constructed from nanometals of atomic precision are important for innovative advances in information storage, energy conversion, and spintronic microdevices. Considerable success has been achieved in designing molecular magnets, which, however, are challenging in preparation and may suffer from drawbacks on the incompatibility of high stability and strong ferromagnetism. Utilizing a state-of-the-art self-developed mass spectrometer and a homemade laser vaporization source, we have achieved a highly efficient preparation of pure iron clusters, and here, we report the finding of a strongly ferromagnetic metal-carbon cluster, Fe12C12-, simply by reacting the Fen- clusters with acetylene in proper conditions. The unique stability of this ferromagnetic Fe12C12- cluster is rooted in a plumb-bob structure pertaining to Jahn-Teller distortion. We classify Fe12C12- as a new member of metallo-carbohedrenes and elucidate its structural stability mechanism as well as its soft-landing deposition and magnetization measurements, providing promise for the exploration of potential applications.
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BACKGROUND: Aging and frailty pose significant challenges globally, placing a substantial burden on healthcare and social services due to their adverse consequences. AIM: The primary objective of this study was to investigate the relationship between social participation and development of frailty transition and trajectory. METHODS: This study utilized data from the CLHLS Cohort, a 10-year follow-up study involving 6713 participants, to investigate the association between social participation and development of frailty. Frailty reflects a comprehensive decline in various body functions. The study employed a group-based trajectory model to analyze the development trajectory of the frailty index and used logistic regression to assess the odds ratio (OR) of frailty risk. RESULTS: We identified two distinct groups of frailty progression trajectories: the "stable development group" and the "rapid growth group." Individuals who engaged in social activities at least once a month, but not daily, exhibited a significant association with an increased risk of transitioning into the "rapid growth group" (OR 1.305, 95% CI 1.032-1.649). Those with social participation less than once a month had an even greater risk (OR 1.872, 95% CI 1.423-2.463). Moreover, low social participation frequency (occasionally/never) has a more pronounced impact on frailty progression in males. CONCLUSION: A higher frequency of social participation is associated with a lower risk of being classified into the "rapid growth group" and a slower rate of frailty index progression. Preventing the progression of frailty can contribute to enhanced support for healthy aging among older adults.
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Fragilidade , Masculino , Humanos , Idoso , Fragilidade/epidemiologia , Estudos Longitudinais , Seguimentos , Envelhecimento , ChinaRESUMO
We investigate Ge3n+1O-/0 (n = 1-3) clusters using anion photoelectron spectroscopy and theoretical calculations. The results show that the lowest energy structure of Ge4O- is a bent Cs symmetric trigonal bipyramidal structure, while Ge4O has a C3v symmetric trigonal bipyramidal structure. Ge7O- has two coexisting low-lying isomers, the first one can be viewed as a Ge2O unit interacting with a Ge5 trigonal bipyramid, the second one can be regarded as an O atom interacting with a Ge7 pentagonal bipyramid; whereas Ge7O has a C3v symmetric structure with a Ge atom and an O atom capping a Ge6 trigonal antiprism from the bottom and top, respectively. The structures of Ge10O- and Ge10O can be obtained by adding an O atom to different binding sites of a C3v symmetric Ge10. Chemical bonding analyses of Ge3n+1O (n = 1-3) reveal that the O atom interacts with its neighboring three Ge atoms forming one 4c-2e σ bond and two 4c-2e π bonds in the top Ge3O trigonal pyramid, while the terminal Ge atom forms one 4c-2e σ bond in the bottom Ge4 trigonal pyramid. The large HOMO-LUMO gaps of Ge3n+1O (n = 1-3) indicate that they have good stabilities. Ab initio molecular dynamics simulations suggest that both Ge7O and Ge10O are dynamically stable in general at 300 and 500 K. The current work suggests that the C3v symmetric Ge3 units and the insertion growth pattern may be viable for constructing 1D germanium oxide nanostructures with the chemical formula of Ge3n+1O.
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A systematic study of the structures and electronic properties of V2-doped silicon clusters, V2Sin-/0 (n = 7-14), was carried out by anion photoelectron spectroscopic experiments combined with theoretical calculations. According to the experimental spectra of V2Sin- (n = 7-14) clusters, the V2Si12- cluster has the highest vertical detachment energy (VDE) of 3.66 eV, while V2Si7- and V2Si14- clusters have lower VDEs of 2.81 and 2.84 eV, respectively. The most stable structure searches find that two V atoms in the V2Sin- clusters with size n = 7 and 8 are located at the surface, while V2Sin- clusters with n ≥ 9 prefer cage-like structures. Based on the analysis of the structural evolution of V2Sin- (n = 9-14) clusters, it can be clearly seen how the antihexagonal prism with one V encapsulated in the cage is gradually built from n = 9 to 12 and further developed from n = 12 to 14 with the extra silicon atoms located at the surface of the Si12 cage. The molecular orbital and the atoms in molecule analysis of the V2Sin- (n = 7-14) anions demonstrate that the strong V-V bond and the delocalized interaction between the V2 moiety and the Sin ligand play a significant role in stabilizing the cluster structures. A strong linear correlation has been found between the Wiberg bond order of the V-V bond and the electron density at the V-V bond critical points.
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The discovery of graphene and its excellent properties inspired the search for more two-dimensional (2D) materials. Understanding the structures and properties of the smallest repeating units as well as crystal 2D materials is helpful for designing 2D materials. As germanium tends to form three-dimensional structures, the preparation of germanium-based 2D nanomaterials is still a challenge. Herein, we report a Ge3O3 cluster with the potential to construct a germanium oxide 2D nanostructure. We conduct a combined anion photoelectron spectroscopy and theoretical study on Ge3O3-/0. The structure of Ge3O3- is a Cs symmetric nonplanar six-membered ring, while that of Ge3O3 is a D3h symmetric planar six-membered ring. Chemical bonding analyses reveal that Ge3O3 exhibits π aromaticity. First-principle results suggest that a buckled honeycomb 2D nanostructure with a wide band gap of 3.14 eV may be produced based on Ge3O3, which is promising in optoelectronic applications especially in blue, violet, and ultraviolet regions.
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The study of C2 Al4 -/0 and C2 Al5 -/0 was conducted using anion photoelectron spectroscopy and quantum chemical computations. The present findings reveal that C2 Al4 - has a boat-like structure, with a single C2 unit surrounded by four aluminum atoms. In contrast, the neutral C2 Al4 species adopts a D2h planar structure with two planar tetracoordinate carbon (ptC) units, consistent with previous reports. Furthermore, the global minimum isomer of C2 Al5 - adopts a D3h symmetry, where the C2 unit interacts with five aluminum atoms. It was also found that a lower symmetry structure of C2 Al5 - , where all five aluminum atoms are located on the same side of the C2 unit, albeit slightly higher in energy compared to the D3h structure. These computations show that the D3h structure of C2 Al5 - is highly stable, exhibiting a large HOMO-LUMO gap.
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Wheat is an essential food crop and its high and stable yield is suffering from great challenges due to the limitations of current breeding technology and various stresses. Accelerating molecularly assisted stress-resistance breeding is critical. Through a meta-analysis of published loci in wheat over the last two decades, we selected 60 loci with main breeding objectives, high heritability, and reliable genotyping, such as stress resistance, yield, plant height, and resistance to spike germination. Then, using genotyping by target sequencing (GBTS) technology, we developed a liquid phase chip based on 101 functional or closely linked markers. The genotyping of 42 loci was confirmed in an extensive collection of Chinese wheat cultivars, indicating that the chip can be used in molecular-assisted selection (MAS) for target breeding goals. Besides, we can perform the preliminary parentage analysis with the genotype data. The most significant contribution of this work lies in translating a large number of molecular markers into a viable chip and providing reliable genotypes. Breeders can quickly screen germplasm resources, parental breeding materials, and intermediate materials for the presence of excellent allelic variants using the genotyping data by this chip, which is high throughput, convenient, reliable, and cost-efficient. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01359-3.