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1.
Asia Pac J Ophthalmol (Phila) ; : 100103, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39326527

RESUMO

PURPOSE: To evaluate the clinical and retinal imaging features of Chinese patients with acute macular neuroretinopathy (AMN) associated with COVID-19. DESIGN: A prospective observational study. METHODS: Retinal imaging, including color fundus photography, near-infrared imaging (NIR), swept-source optical coherence tomography (SS-OCT), optical coherence tomography angiography (OCTA), and Humphrey perimetry, were conducted for each case. RESULTS: All cases were included within the first three months following the pandemic outbreak. A total of 12 male patients (36.36 %) and 21 female patients (63.64 %) were prospectively recruited, and 29 cases (87.88 %) were bilaterally affected. The median interval between the onset of fever and the appearance of ocular symptoms was two days (range, 0.5-5.0 days). Apart from the outer retinal changes typical of AMN, changes in the inner retinal layers were observed, including intraretinal hemorrhage (8.06 %), cotton wool spots (9.68 %), and paracentral acute middle maculopathy (PAMM) (8.06 %). Smaller retinal inner nuclear layer hyperreflective speckles (RIHS) (41.94 %) were identified as a distinguishing feature from typical PAMM. Voids of vessel signals were found in the superficial (11.54 %), intermediate (82.69 %), and deep capillary plexus (98.08 %), and in the choriocapillaris (19.23 %) on OCTA. Humphrey perimetry illustrated central, paracentral, and peripheral scotomas. The occult lesions associated with AMN, PAMM, and some of the RIHS illustrated by OCT were visualized topographically and further confirmed by OCTA as perfusion defects. CONCLUSION: An increase in AMN cases correlated with the SARS-CoV-2 outbreak. Additional features, including widespread inner retinal perfusion deficits, were observed and may serve as potential biomarkers for systemic microcirculation dysregulation in COVID-19.

2.
Front Psychol ; 15: 1381009, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39309146

RESUMO

Introduction: Tai Chi Chuan (TCC) is a traditional Chinese mind-body exercise widely adopted in Chinese communities and colleges. However, the mindful essence of TCC is rarely emphasized during popularization. This makes it difficult for beginners to benefit from it. The present study aimed to examine the effects of a Mindfulness-enhanced Tai Chi Chuan (MTCC) intervention, which enhances mindfulness components embedded within TCC, on mental and physical health among beginners. Methods: A randomized controlled trial was conducted with 119 healthy college students new to Tai Chi Chuan training. Participants were assigned to either the MTCC group or the TCC group. Both interventions consisted of 10 weekly 90-min training sessions, with the MTCC group emphasizing and enhancing mindfulness components. Outcome measures included mindfulness, depression, anxiety, stress, and physical fitness, assessed at baseline and post-intervention. Results: The results showed that the MTCC group had significantly greater improvements than the TCC group in mindfulness, anxiety, stress, and health-and skill-related physical fitness. There were no significant differences between the two groups in depression. Conclusion: The findings suggest that compared to TCC, MTCC can effectively promote individuals' physical fitness and provide additional benefits to mental well-being. MTCC can be recommended as an accessible and beneficial intervention for beginners to improve mental health and strengthen their bodies. Clinical review registration: https://www.chictr.org.cn/, identifier ChiCTR2200058175.

3.
Molecules ; 29(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39125109

RESUMO

Dipines are a type of important antihypertensive drug as L-calcium channel blockers, whose core skeleton is the 1,4-dihydropyridine structure. Since the dihydropyridine ring is a key structural factor for biological activity, the thermodynamics of the aromatization dihydropyridine ring is a significant feature parameter for understanding the mechanism and pathways of dipine metabolism in vivo. Herein, 4-substituted-phenyl-2,6-dimethyl-3,5-diethyl-formate-1,4-dihydropyridines are refined as the structurally closest dipine models to investigate the thermodynamic potential of dipine oxidative metabolism. In this work, the thermodynamic cards of dipine models' aromatization on 21 potential elementary steps in acetonitrile have been established. Based on the thermodynamic cards, the thermodynamic properties of dipine models and related intermediates acting as electrons, hydrides, hydrogen atoms, protons, and two hydrogen ions (atoms) donors are discussed. Moreover, the thermodynamic cards are applied to evaluate the redox properties, and judge or reveal the possible oxidative mechanism of dipine models.


Assuntos
Oxirredução , Termodinâmica , Di-Hidropiridinas/química , Di-Hidropiridinas/metabolismo , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Estrutura Molecular , Modelos Moleculares
4.
Front Plant Sci ; 15: 1431835, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957598

RESUMO

Cotton fiber, the mainstay of the world's textile industry, is formed by the differentiation of epidermal cells on the outer peridium of the ovule. The TBL gene family is involved in the regulation of epidermal hair development as well as response to abiotic stress. However, the function of TBL genes in cotton has not been systematically studied yet. Here, we identified 131 and 130 TBL genes in TM-1 (Gossypium hirsutum) and Hai7124 (Gossypium barbadense), respectively. Phylogenetic, gene structure, expression pattern and cis-element of promoter analysis were performed and compared. Single gene association analysis indicated that more TBL genes related to fiber quality traits were found in G. barbadense, whereas more genes associated with yield traits were found in G. hirsutum. One gene, GhTBL84 (GH_D04G0930), was induced by treatment at 4°C for 12 and 24 h in G. hirsutum and silencing of the GhTBL84 gene by VIGS technology in TM-1 can significantly improve the resistance of cotton seedlings to low temperature stress. In sum, our study conducted a genome-wide identification and comparative analysis of TBL family genes in G. hirsutum and G. barbadense and demonstrated a group of TBL genes significantly associated with fiber quality and excavated cold stress responsive gene, such as GhTBL84, providing a theoretical basis for further improving cotton agronomic traits.

5.
Cardiovasc Diabetol ; 23(1): 192, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844974

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is closely associated with the triglyceride glucose (TyG) index and its related indicators, particularly its combination with obesity indices. However, there is limited research on the relationship between changes in TyG-related indices and CVD, as most studies have focused on baseline TyG-related indices. METHODS: The data for this prospective cohort study were obtained from the China Health and Retirement Longitudinal Study. The exposures were changes in TyG-related indices and cumulative TyG-related indices from 2012 to 2015. The K-means algorithm was used to classify changes in each TyG-related index into four classes (Class 1 to Class 4). Multivariate logistic regressions were used to evaluate the associations between the changes in TyG-related indices and the incidence of CVD. RESULTS: In total, 3243 participants were included in this study, of whom 1761 (54.4%) were female, with a mean age of 57.62 years at baseline. Over a 5-year follow-up, 637 (19.6%) participants developed CVD. Fully adjusted logistic regression analyses revealed significant positive associations between changes in TyG-related indices, cumulative TyG-related indices and the incidence of CVD. Among these changes in TyG-related indices, changes in TyG-waist circumference (WC) showed the strongest association with incident CVD. Compared to the participants in Class 1 of changes in TyG-WC, the odds ratio (OR) for participants in Class 2 was 1.41 (95% confidence interval (CI) 1.08-1.84), the OR for participants in Class 3 was 1.54 (95% CI 1.15-2.07), and the OR for participants in Class 4 was 1.94 (95% CI 1.34-2.80). Moreover, cumulative TyG-WC exhibited the strongest association with incident CVD among cumulative TyG-related indices. Compared to the participants in Quartile 1 of cumulative TyG-WC, the OR for participants in Quartile 2 was 1.33 (95% CI 1.00-1.76), the OR for participants in Quartile 3 was 1.46 (95% CI 1.09-1.96), and the OR for participants in Quartile 4 was 1.79 (95% CI 1.30-2.47). CONCLUSIONS: Changes in TyG-related indices are independently associated with the risk of CVD. Changes in TyG-WC are expected to become more effective indicators for identifying individuals at a heightened risk of CVD.


Assuntos
Biomarcadores , Glicemia , Doenças Cardiovasculares , Obesidade , Triglicerídeos , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/sangue , Estudos Prospectivos , Triglicerídeos/sangue , Incidência , Medição de Risco , China/epidemiologia , Glicemia/metabolismo , Obesidade/epidemiologia , Obesidade/diagnóstico , Obesidade/sangue , Idoso , Biomarcadores/sangue , Estudos Longitudinais , Fatores de Tempo , Prognóstico , Fatores de Risco de Doenças Cardíacas , Valor Preditivo dos Testes , Fatores de Risco
6.
J Org Chem ; 89(9): 6205-6221, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38632842

RESUMO

Organic hydride/acid pairs have been reported as multisite proton-coupled electron transfer (MS-PCET) reagents in reductive MS-PCET reactions recently. Since the key step for an organic hydride/acid pair acting as an MS-PCET reagent is a chemical process of the organic hydride/acid pair releasing a formal hydrogen atom, the bond dissociation free energy of the organic hydride/acid pair releasing a formal hydrogen atom is a valuable thermodynamic parameter for objectively evaluating the thermodynamic potential for an organic hydride/acid pair to act as an MS-PCET reagent. Now, organic hydride/acid pairs of 216 organic hydrides have been demonstrated to be a potential type of thermodynamically potential-regulated MS-PCET reagent. Without a doubt, organic hydride/acid pairs reflect the change of N-substituted organic hydrides from simple hydride reductants to thermodynamically-regulated MS-PCET reagents, which could significantly expand the availability of novel MS-PCET reagents.

7.
J Chem Phys ; 160(16)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38647307

RESUMO

In recent years, the exploration of solar absorbers has grown in favor due to the scarcity of energy. Here, we propose an absorber with an array of a circular ring surrounding disk (RSD) for solar energy capture. The novel structure keeps above 93.5% absorption with an average absorption of 96.95% in wavelengths from 300 to 4000 nm. Meanwhile, the proposed absorber is advantageous in that the structure is generalizable to other metals and dielectric materials. Furthermore, the data results show that the absorber has polarization-independent properties as well as maintaining >90% absorption in the considered wavelength range up to an incidence angle of 52° and >95% absorption at large process tolerances. Finally, the excellent absorption under the AM1.5 solar spectrum demonstrates the RSD absorber's ability to capture solar energy. These results show the potential of the absorber for applications in electromagnetic invisibility cloaking, thermal emitters, and solar energy capture and conversion.

8.
BMC Med ; 22(1): 27, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38317125

RESUMO

BACKGROUND: New "noncardiac" problems in children with congenital heart disease (CHD), such as developmental delay or long-term neurodevelopmental impairments, have attracted considerable attention in recent years. It is hypothesized that exercise might attenuate CHD-associated neurodevelopmental impairments; however, this has not been thoroughly investigated. The objective of this prospective, single-blinded, randomized controlled experiment was to evaluate the impact of customized home-based exercise for children with CHD. METHODS: Children aged 0-5 years with echocardiography-confirmed simple CHD subtypes who were scheduled to undergo cardiac catheterization were screened for enrolment. Among 420 screened CHD children, 192 were enrolled and randomly assigned at a 1:1 ratio to receive a 6-month intervention (30 min daily customized home-based exercise program with supervision for no less than 5 days per week, combined with home-based exercise education) or control treatment (home-based education). The primary outcome was motor development (gross motor quotient (GMQ), fine motor quotient (FMQ), and total motor quotient (TMQ)). The secondary outcomes were cardiac function and structure, bone quality, physical development, parental anxiety, caregiver burden, and quality of life. Children and their families were assessed before and 1, 3, and 6 months after catheterization; 183 (95.3%) children were included in the primary analysis. RESULTS: After 6-month treatment, the intervention group significantly increased their motor quotient, which was consistently higher than that of the control group (GMQ p < 0.0001, FMQ p = 0.02, TMQ p < 0.001). The physical developments in height, weight, and circumferences of the upper-arm, chest, and head were also significantly improved by exercise (all p < 0.017). No significant improvements in the bone strength or the cardiac structure and function were found among patients in the intervention group (all p > 0.017). For parents, higher quality of life level (total score p = 0.016) was observed in the intervention group; while effects of exercise on the anxiety (rude score p = 0.159, standard score p = 0.159) or the Zarit caregiver burden scale score (p = 0.404) were non-significant. No adverse events occurred during the study period. CONCLUSIONS: Customized home-based exercise improved motor development in children with CHD. While the long-term effects of parent training in home-based exercise are unknown, the study results suggest positive outcomes. TRIAL REGISTRATION: A home-based exercise program in congenital heart disease children with cardiac catheterization: a randomized controlled trial. ( http://www.chictr.org.cn/ , ChiCTR-IOR-16007762, January 14, 2016).


Assuntos
Cardiopatias Congênitas , Testes Psicológicos , Qualidade de Vida , Autorrelato , Criança , Humanos , Estudos Prospectivos , Cardiopatias Congênitas/terapia , Pais
9.
RSC Adv ; 14(1): 222-232, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38173608

RESUMO

N-heterocycles are important chemical hydrogen-storage materials, and the acceptorless dehydrogenation and hydrogenation of N-heterocycles as organic hydrogen carriers have been widely studied, with the main focus on the catalyst synthesis and design, investigation of the redox mechanisms, and extension of substrate scope. In this work, the Gibbs free energies of the dehydrogenation of pre-aromatic N-heterocycles (YH2) and the hydrogenation of aromatic N-heterocycles (Y), i.e., ΔGH2R(YH2) and ΔGH2A(Y), were derived by constructing thermodynamic cycles using Hess' law. The thermodynamic abilities for the acceptorless dehydrogenation and hydrogenation of 78 pre-aromatic N-heterocycles (YH2) and related 78 aromatic N-heterocycles (Y) were well evaluated and discussed in acetonitrile. Moreover, the applications of the two thermodynamic parameters in identifying pre-aromatic N-heterocycles possessing reversible dehydrogenation and hydrogenation properties and the selection of the pre-aromatic N-heterocyclic hydrogen reductants in catalytic hydrogenation were considered and are discussed in detail. Undoubtedly, this work focuses on two new thermodynamic parameters of pre-aromatic and aromatic N-heterocycles, namely ΔGH2R(YH2) and ΔGH2A(Y), which are important supplements to our previous work to offer precise insights into the chemical hydrogen storage and hydrogenation reactions of pre-aromatic and aromatic N-heterocycles.

10.
PLoS One ; 19(1): e0297126, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241257

RESUMO

In recent years, buckwheat (Fagopyrum spp.) is being increasingly damaged by the Siberian tortoise beetle (Rhinoncus sibiricus Faust). Adults and nymphs feed on leaf tissues and caulicles, thus damaging its stems and leaves. In this study, we investigated the habits, distribution, and environmental impact of R. sibiricus using MaxEnt, an ecological niche model. Geographic information about the infestation site from previous field surveys and climatic data from 2013 to 2018 were organized and optimized using R. The impact factors were calculated using MaxEnt software. The results indicate that population fluctuations in R. sibiricus are related to changes in temperature, humidity, and their spatial distribution. Under current climatic conditions, R. sibiricus is mainly distributed in northern China, with sporadic distribution in south-western China. The values for a survival probability threshold > 0.3 were: precipitation during the wettest month (bio13), 70.31-137.56 mm; mean temperature of the coldest quarter (bio11), -15.00-0.85°C; mean temperature of the warmest quarter (bio10), 11.88-23.16°C; precipitation during the coldest quarter (biol9), 0-24.39 mm. The main factors contributing > 70% to the models were precipitation during the wettest month and coldest quarter, and mean temperature during the warmest and coldest quarters. Under both future climate models, the center of the fitness zone moves northward. Our results will be useful in guiding administrative decisions and support farmers interested in establishing control and management strategies for R. sibiricus. This study could also serve as a reference for future research on other invasive pests.


Assuntos
Fagopyrum , Gorgulhos , Animais , Temperatura , Modelos Teóricos , Temperatura Baixa , China , Ecossistema , Mudança Climática
11.
Medicine (Baltimore) ; 103(3): e36891, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38241595

RESUMO

Immunotherapy is less efficient for epithelial ovarian cancer and lacks ideal biomarkers to select the best beneficiaries for immunotherapy. CX3CR1 as chemokine receptor mainly expressed on immune cell membranes, and combined with its unique ligand CX3CL1, mediates tissue chemotaxis and adhesion of immune cells. However, the immune functional and prognostic value of CX3CR1 in epithelial ovarian cancer has not been clarified. A comprehensive retrospective analysis was performed by using the online database to identify the underlying immunological mechanisms and prognostic value of CX3CR1. The Human Protein Atlas, gene expression profiling interactive analysis, and TISIDB (an integrated repository portal for tumor-immune system interactions) database showed that CX3CR1 expressed higher in epithelial ovarian cancer than that in normal ovarian tissue. Four hundred twenty-two cases from Gene Expression Profiling Interactive Analysis and 1656 cases from Kaplan-Meier plotter database showed higher expression of CX3CR1 (above median) was associated with unfavorable overall survival. TIMER, UALCAN, and TISIDB database were applied to validate CX3CR1 negative impact on overall survival. In addition, correlation analysis showed that the expression level of CX3CR1 was positive association with infiltrating levels of B cells (R = 0.31, P = 3.10e-12), CD8+ T cells (R = 0.26, P = 7.93e-09), CD4+ T cells (R = 0.11, P = 1.41e-02), macrophages (R = 0.32, P = 4.29e-13), dendritic cells (R = 0.27, P = 2.98e-09), and neutrophil (R = 0.25, P = 3.25e-08) in epithelial ovarian cancer. Therefore, CX3CR1 involved in reshaping the immune microenvironment for epithelial ovarian cancer and maybe a potential immunotherapy target and prognostic marker for ovarian cancer.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Carcinoma Epitelial do Ovário , Estudos Retrospectivos , Prognóstico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Biomarcadores , Biomarcadores Tumorais/metabolismo , Microambiente Tumoral , Receptor 1 de Quimiocina CX3C/genética
12.
Cardiovasc Diabetol ; 23(1): 40, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254088

RESUMO

BACKGROUND: The triglyceride-glucose (TyG) index is regarded as a dependable alternative for assessing insulin resistance (IR), given its simplicity, cost-effectiveness, and strong correlation with IR. The relationship between the TyG index and adverse outcomes in patients with coronary heart disease (CHD) is not well established. This study examines the association of the TyG index with long-term adverse outcomes in hospitalized CHD patients. METHODS: In this single-center prospective cohort study, 3321 patients hospitalized with CHD were included. Multivariate Cox regression models were employed to assess the associations between the TyG index and the incidence of all-cause mortality and major adverse cardiovascular events (MACEs). To examine potential nonlinear associations, restricted cubic splines and threshold analysis were utilized. RESULTS: During a follow-up period of 9.4 years, 759 patients (22.9%) succumbed to mortality, while 1291 (38.9%) experienced MACEs. Threshold analysis demonstrated a significant "U"-shaped nonlinear relationship with MACEs, with different hazard ratios observed below and above a TyG index of 8.62 (below: HR 0.71, 95% CI 0.50-0.99; above: HR 1.28, 95% CI 1.10-1.48). Notably, an increased risk of all-cause mortality was observed only when the TyG index exceeded 8.77 (HR 1.53, 95% CI 1.19-1.96). CONCLUSIONS: This study reveals a nonlinear association between the TyG index and both all-cause mortality and MACEs in hospitalized CHD patients with CHD. Assessing the TyG index, particularly focusing on individuals with extremely low or high TyG index values, may enhance risk stratification for adverse outcomes in this patient population.


Assuntos
Doença da Artéria Coronariana , Resistência à Insulina , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Estudos Prospectivos , Glucose , Triglicerídeos
13.
Molecules ; 28(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38138528

RESUMO

Compounds with benzopyran as the core structure play an important role in the total synthesis of antioxidants, drugs, and natural products. Herein, the thermodynamic data of benzopyran compounds and their intermediates were measured and calculated by combining thermodynamics with kinetics. The mechanism of reactions between four benzopyran compounds and organic hydride acceptors was proven to be a one-step hydride transfer. The thermodynamic properties of these compounds and their corresponding intermediates were elucidated. The rationality and accuracy of the electrochemical measurement method were proved. Furthermore, the essential rule of unique structures being present between the C-H bond and para-substituent constants on the benzene ring, as shown in previous studies, was investigated. A simultaneous correlation between thermodynamics and kinetics was found for the hydride transfer reaction, in which the reaction site is connected with the substituent through the benzene ring, a double bond, or a N atom. The likely reason for the correlation between thermodynamic and kinetic is that the benzene ring, double bond, or N atom have the role of transferring the electronic effect. This finding can be applied to the calculation of the activation energy of hydride self-exchange reactions, the prediction of kinetic isotope effects, and explorations of selective reduction processes of hydride transfer in such organic hydride compounds.

14.
Clin Exp Med ; 23(8): 4597-4608, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37914966

RESUMO

Inflammation and nutrition related proteins participate in the development of acute myeloid leukemia (AML). It has been reported that the albumin-to-fibrinogen ratio (AFR) could serve as a prognostic indicator in patients with malignancy, but the precise relevance of AML is unclear. This study aimed to evaluate the effect of AFR on survival prognosis in patients with AML. We analyzed 227 patients newly diagnosed with non-M3 AML. AFR was calculated as albumin divided by fibrinogen. Based on the cutoff point from X-tile program, patients were divided into AFR-high (38.8%) and AFR-low (61.2%) groups. AFR-low group showed a poorer complete remission rate (P < 0.001) and median time to relapse (P = 0.026), while the mortality was higher (P = 0.009) than AFR-high ones. According to the log-rank test, AFR-low group had shorter OS (P < 0.001) and DFS (P = 0.034). Multivariate analysis identified AFR, ELN risk, bone marrow transplant, and hemoglobin as independent prognostic variables associated with OS. A visualized nomogram for predicting OS was performed. The C-index (0.75), calibration plots, and decision curve analyses of new model showed better discrimination, calibration, and net benefits than the ELN risk model. The time-dependent receiver operating characteristic (ROC) curve of 1-, 2-, and 3-year also functioned well (AUC, 0.81, 0.93 and 0.90, respectively). Our study provided a comprehensive view of AFR which could be an independent prognostic indicator in AML patients. The prognostic model utilized readily available information from ordinary clinical practice to improve predictive performance, identify risks, and assist in therapeutic decision-making.


Assuntos
Fibrinogênio , Leucemia Mieloide Aguda , Humanos , Prognóstico , Albuminas/metabolismo , Nomogramas , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia
15.
ACS Omega ; 8(35): 31984-31997, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692224

RESUMO

Since the hydrogenation of imines (X) and the dehydrogenation of amines (XH2) generally involve the two hydrogen ions (H- + H+) transfer, the thermodynamic abilities of various amines releasing hydrides or two hydrogen ions as well as various imines accepting protons or two hydrogen ions are important and characteristic physical parameters. In this work, the pKa values of 84 protonated imines (XH+) in acetonitrile were predicted. Combining Gibbs free energy changes of amines releasing hydrides in acetonitrile from our previous work with the pKa(XH+) values, the Gibbs free energy changes of amines releasing two hydrogen ions and imines accepting two hydrogen ions were derived using Hess's law by constructing thermochemical cycles, and the thermodynamic evaluations of amines as hydrides or two hydrogen ions reductants and imines as protons or two hydrogen ions acceptors are well compared and discussed. Eventually, the practical application of thermodynamic data for amines and imines on hydrogenation feasibility, mechanism, and possible elementary steps was shown and discussed in this paper from the point of thermodynamics.

16.
Cell Res ; 33(9): 661-678, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37460804

RESUMO

Studies of cultured embryos have provided insights into human peri-implantation development. However, detailed knowledge of peri-implantation lineage development as well as underlying mechanisms remains obscure. Using 3D-cultured human embryos, herein we report a complete cell atlas of the early post-implantation lineages and decipher cellular composition and gene signatures of the epiblast and hypoblast derivatives. In addition, we develop an embryo-like assembloid (E-assembloid) by assembling naive hESCs and extraembryonic cells. Using human embryos and E-assembloids, we reveal that WNT, BMP and Nodal signaling pathways synergistically, but functionally differently, orchestrate human peri-implantation lineage development. Specially, we dissect mechanisms underlying extraembryonic mesoderm and extraembryonic endoderm specifications. Finally, an improved E-assembloid is developed to recapitulate the epiblast and hypoblast development and tissue architectures in the pre-gastrulation human embryo. Our findings provide insights into human peri-implantation development, and the E-assembloid offers a useful model to disentangle cellular behaviors and signaling interactions that drive human embryogenesis.


Assuntos
Embrião de Mamíferos , Camadas Germinativas , Humanos , Embrião de Mamíferos/metabolismo , Implantação do Embrião , Endoderma , Mesoderma/metabolismo , Desenvolvimento Embrionário
17.
J Chem Phys ; 159(1)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37417751

RESUMO

In this paper, a broadband metamaterial absorber consisting of the doped silicon substrate and the square array of doped silicon covered by a SU-8 layer is presented. The target structure achieves an average absorption of 94.42% in the studied frequency range (0.5-8 THz). In particular, the structure exceeds 90% absorption in the frequency range of 1.44-8 THz, which is a significant increase in bandwidth relative to reported devices of the same type. Next, the near-perfect absorption of the target structure is verified by the impedance matching principle. Furthermore, through the analysis of the electric field distribution inside the structure, the physical mechanism of its broadband absorption is investigated and explained. Finally, the impact of fluctuations in the incident angle, polarization angle, and structural parameters on the absorption efficiency is examined at length. The analysis shows that the structure has characteristics, such as polarization insensitivity, wide-angle absorption, and good process tolerance. The proposed structure is advantageous for applications in THz shielding, cloaking, sensing, and energy harvesting.


Assuntos
Eletricidade , Silício
18.
Zootaxa ; 5306(2): 232-242, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37518526

RESUMO

The generic diagnostic characters of Paracercopis (Hemiptera: Cercopoidea: Cercopidae) are redefined and the autapomorphies are proposed to support the monophyly of the genus. Scanning electron micrographs of antennal sensilla and sensilla on rostral apex of P. seminigra (Melichar, 1902) are provided for the first time. A checklist together with new distribution records and key to the species of the genus are provided. Host plant associations of Paracercopis species are reported for the first time. Paracercopis unicolor Liang, Zhang & Xiao, sp. nov., representing the seventh and largest species of the genus is described from Hubei Province in south central China.


Assuntos
Hemípteros , Animais , China , Microscopia , Sensilas
19.
ACS Phys Chem Au ; 3(4): 358-373, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37520315

RESUMO

It is well-known that for an electron transfer reaction, the electron-donating ability of electron donors and the electron-accepting ability of electron acceptors can be quantitatively described by the oxidation potential of electron donors and the reduction potential of electron acceptors. However, for an electron transfer reaction, the electron-donating activity of electron donors and the electron-accepting activity of electron acceptors cannot be quantitatively described by a characteristic parameter of electron donors and a characteristic parameter of electron acceptors till now. In this paper, a characteristic activity parameter of electron donors and electron acceptors named as their thermo-kinetic parameter is proposed to quantify the electron-donating activity of electron donors and the electron-accepting activity of electron acceptors in electron transfer reactions. At the same time, the thermo-kinetic parameter values of 70 well-known electron donors and the corresponding 70 conjugated electron acceptors in acetonitrile at 298 K are determined. The activation free energies of 4900 typical electron transfer reactions in acetonitrile at 298 K are estimated according to the thermo-kinetic parameter values of 70 electron donors and 70 conjugated electron acceptors, and the estimated results have received good verification of the corresponding independent experimental measurements. The physical meaning of the thermo-kinetic parameter is examined. The relationship of the thermo-kinetic parameter with the corresponding redox potential as well as the relationship of the activation free energy with the corresponding thermodynamic driving force of electron transfer reactions is examined. The results show that the observed relationships between the thermo-kinetic parameters and the redox potentials as well as the observed relationships between the activation free energy and the thermodynamic driving force depend on the choice of electron donors and electron acceptors as well as the electron transfer reactions. The greatest contribution of this paper is to realize the symmetry and unification of kinetic equations and the corresponding thermodynamic equations of electron transfer reactions.

20.
RSC Adv ; 13(23): 16023-16033, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37260565

RESUMO

Nitrogen-containing heterocycles are an important class of antioxidants, and their reactivity and selectivity in hydrogen atom reactions have attracted significant interest from chemists. In this work, the kinetics of hydrogen atom transfer reactions from C(sp3)-H bonds of 28 nitrogen-containing heterocycles, oxygen-containing heterocycles, alicyclic amines and cycloalkanes, which were denoted as XH, to the CumO˙ radical, were investigated. The characteristic physical parameter of the substrate, i.e., the thermo-kinetic parameter ΔG≠o(XH), was determined using the kinetic equation [ΔG≠XH/Y = ΔG≠o(XH) + ΔG≠o(Y)] to quantitatively evaluate the H-donating ability of XH. The effects of the substrate structure, substituent attached to the nitrogen atom, and ring size on the H-donating ability were discussed carefully. By comparing the H-donating abilities of cycloalkanes, alicyclic amines and nitrogen/oxygen-containing heterocycles, the influence of the introduction of N, O, or carbonyl groups in the carbon ring on the H-donating ability of C(sp3)-H bond was determined. The electronic, steric and stereo-electronic effects of the groups were also discussed. Herein, we not only quantitatively determined the H-donating ability of the substrate, but also provided ideas for the synthesis of new antioxidants.

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