Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Sci Rep ; 14(1): 7278, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538674

RESUMO

Brucella, a gram-negative intracellular bacterium, causing Brucellosis, a zoonotic disease with a range of clinical manifestations, from asymptomatic to fever, fatigue, loss of appetite, joint and muscle pain, and back pain, severe patients have developed serious diseases affecting various organs. The mRNA vaccine is an innovative type of vaccine that is anticipated to supplant traditional vaccines. It is widely utilized for preventing viral infections and for tumor immunotherapy. However, research regarding its effectiveness in preventing bacterial infections is limited. In this study, we analyzed the epitopes of two proteins of brucella, the TonB-dependent outer membrane receptor BtuB and the LPS assembly protein LptD, which is involved in nutrient transport and LPS synthesis in Brucella. In order to effectively stimulate cellular and humoral immunity, we utilize a range of immunoinformatics tools such as VaxiJen, AllergenFPv.1.0 and SignalP 5.0 to design proteins. Finally, five cytotoxic T lymphocyte (CTL) cell epitopes, ten helper T lymphocyte (HTL) cell epitopes, and eight B cell epitopes were selected to construct the vaccine. Computer simulations are also used to verify the immune response of the vaccine. The codon optimization, in silico cloning showed that the vaccine can efficiently transcript and translate in E. coli. The secondary structure of mRNA vaccines and the secondary and tertiary structures of vaccine peptides were predicted and then docked with TLR-4. Finally, the stability of the developed vaccine was confirmed through molecular dynamics simulation. These analyses showed that the design the multi-epitope mRNA vaccine could potentially target extracellular protein of prevalent Brucella, which provided novel strategies for developing the vaccine.


Assuntos
Brucella , Proteínas de Escherichia coli , Vacinas , Humanos , Brucella/genética , Vacinas de mRNA , Escherichia coli , Lipopolissacarídeos , Epitopos de Linfócito T , Epitopos de Linfócito B , Linfócitos T Citotóxicos , Simulação de Dinâmica Molecular , Vacinas de Subunidades , Biologia Computacional , Simulação de Acoplamento Molecular , Proteínas da Membrana Bacteriana Externa/genética
2.
Microb Pathog ; 188: 106557, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272330

RESUMO

The Notch signaling pathway is the most crucial link in the normal operation and maintenance of physiological functions of mammalian life processes. Notch receptors interact with ligands and this leads to three cleavages and goes on to enter the nucleus to initiate the transcription of target genes. The Notch signaling pathway deeply participates in the differentiation and function of various cells, including immune cells. Recent studies indicate that the outcomes of Notch signaling are changeable and highly dependent on different bacterial infection. The Notch signaling pathway plays a different role in promoting and inhibiting bacterial infection. In this review, we focus on the latest research findings of the Notch signaling pathway in bacterial infectious diseases. The Notch signaling pathway is critically involved in a variety of development processes of immunosuppression of different APCs. The Notch signaling pathway leads to functional changes in epithelial cells to aggravate tissue damage. Specifically, we illustrate the regulatory mechanism of the Notch signaling pathway in various bacterial infections, such as Mycobacterium tuberculosis, Mycobacterium avium paratuberculosis, Mycobacterium leprae, Helicobacter pylori, Klebsiella pneumoniae, Bacillus subtilis, Staphylococcus aureus, Ehrlichia chaffeensis and sepsis. Collectively, this review will not only help beginners intuitively and systematically understand the Notch signaling pathway in bacterial infectious diseases but also help experts to generate fresh insight in this field.


Assuntos
Infecções Bacterianas , Doenças Transmissíveis , Mycobacterium tuberculosis , Animais , Humanos , Transdução de Sinais , Receptores Notch/metabolismo , Mycobacterium tuberculosis/metabolismo , Mamíferos/metabolismo
3.
Angew Chem Int Ed Engl ; 63(7): e202315371, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38014650

RESUMO

The high-entropy approach is applied to monoclinic Prussian White (PW) Na-ion cathodes to address the issue of unfavorable multilevel phase transitions upon electrochemical cycling, leading to poor stability and capacity decay. A series of Mn-based samples with up to six metal species sharing the N-coordinated positions was synthesized. The material of composition Na1.65 Mn0.4 Fe0.12 Ni0.12 Cu0.12 Co0.12 Cd0.12 [Fe(CN)6 ]0.92 □0.08 ⋅ 1.09H2 O was found to exhibit superior cyclability over medium/low-entropy and conventional single-metal PWs. We also report, to our knowledge for the first time, that a high-symmetry crystal structure may be advantageous for high-entropy PWs during battery operation. Computational comparisons of the formation enthalpy demonstrate that the compositionally less complex materials are prone to phase transitions, which negatively affect cycling performance. Based on data from complementary characterization techniques, an intrinsic mechanism for the stability improvement of the disordered PW structure upon Na+ insertion/extraction is proposed, namely the dual effect of suppression of phase transitions and mitigation of gas evolution.

4.
PLoS One ; 18(8): e0286358, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37561685

RESUMO

Brucellosis is a common zoonosis, which is caused by Brucella infection, and Brucella often infects livestock, leading to abortion and infertility. At present, human brucellosis remains one of the major public health problems in China. According to previous research, most areas in northwest China, including Xinjiang, Tibet, and other regions, are severely affected by Brucella. Although there are vaccines against animal Brucellosis, the effect is often poor. In addition, there is no corresponding vaccine for human Brucellosis infection. Therefore, a new strategy for early prevention and treatment of Brucella is needed. A multi-epitope vaccine should be developed. In this study, we identified the antigenic epitopes of the Brucella type IV secretion system VirB8 and Virb10 using an immunoinformatics approach, and screened out 2 cytotoxic T lymphocyte (CTL) epitopes, 9 helper T lymphocyte (HTL) epitopes, 6 linear B cell epitopes, and 6 conformational B cell epitopes. These advantageous epitopes are spliced together through different linkers to construct a multi-epitope vaccine. The silico tests showed that the multi-epitope vaccine was non-allergenic and had a strong interaction with TLR4 molecular docking. In immune simulation results, the vaccine construct may be useful in helping brucellosis patients to initiate cellular and humoral immunity. Overall, our findings indicated that the multi-epitope vaccine construct has a high-quality structure and suitable characteristics, which may provide a theoretical basis for the development of a Brucella vaccine.


Assuntos
Brucella , Brucelose , Vacinas , Animais , Humanos , Sistemas de Secreção Tipo IV , Epitopos de Linfócito B , Simulação de Acoplamento Molecular , Epitopos de Linfócito T , Brucelose/prevenção & controle , Biologia Computacional/métodos , Vacinas de Subunidades
5.
J Biomol Struct Dyn ; : 1-19, 2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37424209

RESUMO

Chronic infection induced by immune tolerance to hepatitis B virus (HBV) is one of the most common causes of hepatic cirrhosis and hepatoma. Fortunately, the application of therapeutic vaccine can not only reverse HBV-tolerance, but also serve a potentially effective therapeutic strategy for treating chronic hepatitis B (CHB). However, the clinical effect of the currently developed CHB therapeutic vaccine is not optimistic due to the weak immunogenicity. Given that the human leukocyte antigen CTLA-4 owns strong binding ability to the surface B7 molecules (CD80 and CD86) of antigen presenting cell (APCs), the immunoglobulin variable region of CTLA-4 (IgV_CTLA-4) was fused with the L protein of HBV to contrive a novel therapeutic vaccine (V_C4HBL) for CHB in this study. We found that the addition of IgV_CTLA-4 did not interfere with the formation of L protein T cell and B cell epitopes after analysis by means of immunoinformatics approaches. Meanwhile, we also found that the IgV_CTLA-4 had strong binding force to B7 molecules through molecular docking and molecular dynamics (MD) simulation. Notably, our vaccine V_C4HBL showed good immunogenicity and antigenicity by in vitro and in vivo experiments. Therefore, the V_C4HBL is promising to again effectively activate the cellular and humoral immunity of CHB patients, and provides a potentially effective therapeutic strategy for the treatment of CHB in the future.Communicated by Ramaswamy H. Sarma.

6.
Medicine (Baltimore) ; 102(28): e34232, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37443519

RESUMO

The care model composed of a multidisciplinary team is the best model to promote stroke rehabilitation. The objective of this study was to explore the effect of nurse-led rapid rehabilitation on mechanical thrombectomy (MT) in patients with acute ischemic stroke (AIS). This study used a non-randomized, historically controlled clinical trial design to compare the efficacy of nurse-led rapid and routine rehabilitation after thrombectomy in patients with ischemic stroke. Treatment outcomes, including hospitalization duration, hospitalization costs, scores on multiple scales at discharge, and clinical outcomes 3 months post-discharge, were assessed and compared between the 2 rehabilitation approaches. Our report is based on the STROBE guidelines. The differences in length of stay in hospital (P = .018), hospitalization expense (P < .001), National Institutes of Health Stroke Scale score (NIHSS) score at discharge (P < .001), modified Rankin scale (MRS) score at discharge (P < .001), and ADL (Activities of Daily Living) score at discharge (P = .156) between the intervention group and the control group were statistically significant. There were statistically significant differences in anxiety/depression (P = .013) and overall quality of life (P = .017) 3 months after discharge. Generalized estimating equation (GEE) analysis showed that interaction effects between group and time were statistically significant for MRS (OR = 0.231, 95% confidence interval: 0.128-0.417, P < .001). The hospitalization time of patients in the intervention group was shortened, and the hospitalization cost was reduced. There were differences in psychological status, and the overall quality of life and improvement of disability status was better.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/psicologia , AVC Isquêmico/cirurgia , Atividades Cotidianas , Qualidade de Vida , Estudo Historicamente Controlado , Assistência ao Convalescente , Papel do Profissional de Enfermagem , Alta do Paciente , Resultado do Tratamento , Trombectomia , Isquemia Encefálica/cirurgia , Estudos Retrospectivos
7.
J Phys Chem Lett ; 14(18): 4304-4312, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37129553

RESUMO

Two-dimensional (2D) Dion-Jacobson (DJ) hybrid perovskites with exceptional stability and enhanced out-of-plane carrier transport are regarded as one of the competive candidates for constructing next-generation photodetectors. However, the studies of DJ hybrid perovskites on weak light detection remain scarce, and the devices based on them usually show relatively poor weak light detection ability, with a detection limit of around µW/cm2. Herein, a new DJ hybrid perovskite (3AMPY)(MA)Pb2Br7 [3AMPY is 3-(aminomethyl)pyridinium, and MA is methylammonium] with short interlayer spacing and more lattice rigidity is obtained. The devices based on (3AMPY)(MA)Pb2Br7 crystals exhibit an ultrahigh sensibility to weak light at 377 and 405 nm, with an extremely low detection limit of ∼70 nW/cm2. Moreover, the on/off ratios and detectivity of the devices can reach ∼103 and ∼1012 Jones at both 377 and 405 nm, respectively. This work highlights great potential of DJ hybrid perovskites toward weak light detection.

8.
PLoS One ; 18(4): e0284657, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37083919

RESUMO

OBJECTIVES: To explore the status and related factors of knowledge, attitude, and practice (KAP) of poststroke dysphagia among neurological nurses in China. METHODS: Neurological nurses from 40 tertiary hospitals in Southwest China were invited to complete a survey on the knowledge, attitude, and practice of the nursing of poststroke dysphagia. We used a questionnaire to collect the participants' information including the basic characteristics and the KAP Questionnaire on poststroke dysphagia in the neurological ward. A sample of 707 participants completed the survey. RESULTS: The knowledge, attitude, and practice scores for the nursing of poststroke dysphagia were 12.00±4.09, 71.99±11.00, 52.22±9.08, respectively. The total score of knowledge towards the nursing of poststroke dysphagia was significantly different among nurses with different ages, working time of nursing, working time of nursing in neurology, the highest level of education, professional title, position, the method of training, the number of dysphagia-related nursing trainings, the total length of dysphagia nursing training, and the nursing basis of patients with dysphagia. The total score of attitudes towards the nursing of poststroke dysphagia was significantly different among nurses with the way they were trained, and the nursing basis for patients with dysphagia. The total score of practice towards poststroke dysphagia was significantly different among nurses with the number of dysphagia-related nursing trainings, the total length of dysphagia nursing training, the training method, and the basis of nursing patients with dysphagia. CONCLUSION: Neurological nurses' knowledge score in poststroke dysphagia is relatively low, and the knowledge level needs improvement. The attitude and practice score of neurological nurses in dysphagia after stroke was much better than the knowledge score. Managers and nursing researchers should develop and offer effective training for neurological nurses to improve their knowledge, attitude and practice towards poststroke dysphagia, and then improve patients' health outcomes.


Assuntos
Transtornos de Deglutição , Enfermeiras e Enfermeiros , Humanos , Estudos Transversais , Atitude do Pessoal de Saúde , Transtornos de Deglutição/etiologia , Conhecimentos, Atitudes e Prática em Saúde , Competência Clínica , China , Inquéritos e Questionários
9.
Antioxidants (Basel) ; 11(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36358493

RESUMO

As a kind of medicine and food homologous plant, kudzu root (Pueraria lobata (Willd.) Ohwi) is called an "official medicine" in Chinese folk medicine. Puerarin is the main active component extracted from kudzu root, and its structural formula is 8-ß-D-grapes pyranose-4, 7-dihydroxy isoflavone, with a white needle crystal; it is slightly soluble in water, and its aqueous solution is colorless or light yellow. Puerarin is a natural antioxidant with high health value and has a series of biological activities such as antioxidation, anti-inflammation, anti-tumor effects, immunity improvement, and cardio-cerebrovascular and nerve cell protection. In particular, for the past few years, it has also been extensively used in clinical study. This review focuses on the antioxidant activity of puerarin, the therapy of diverse types of inflammatory diseases, various new drug delivery systems of puerarin, the "structure-activity relationship" of puerarin and its derivatives, and pharmacokinetic and clinical studies, which can provide a new perspective for the puerarin-related drug research and development, clinical application, and further development and utilization.

10.
Food Funct ; 13(23): 11945-11953, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36383179

RESUMO

Cardiovascular diseases (CVDs) represent the leading cause of mortality worldwide. As a complex matrix of micronutrients, phytochemicals and sugars, the effects of orange juice (OJ) on CVD risk factors in overweight and obese adults warrant investigation. Hence, this systematic review and meta-analysis of randomized controlled trials (RCTs) evaluated the effect of chronic OJ consumption on the lipid profile, blood pressure, glycemic indices and inflammatory biomarkers in overweight and obese adults. Four databases were searched from inception until May 2022 and eight studies were included in the final analysis. Pooled results demonstrated the beneficial effect of OJ on systolic blood pressure (MD: -0.98 mmHg, 95% CI [-1.52, -0.44], p = 0.000, I2 = 0.0%) and HDL-C (SMD: 0.29, 95% CI [0.03, 0.54], p = 0.027, I2 = 0.0%) compared to the control group. However, total cholesterol, TG, LDL-C, glucose, insulin, HOMA-IR and CRP did not change following chronic OJ consumption. This meta-analysis demonstrates the beneficial effects of chronic OJ consumption on blood pressure and HDL-C in overweight and obese adults.


Assuntos
Doenças Cardiovasculares , Citrus sinensis , Adulto , Humanos , Sobrepeso , Ensaios Clínicos Controlados Aleatórios como Assunto , Obesidade , Fatores de Risco de Doenças Cardíacas , Doenças Cardiovasculares/prevenção & controle
11.
Contemp Nurse ; 58(4): 264-275, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36052463

RESUMO

AIM: To evaluate the relationship between nursing assessment findings at discharge and acute ischaemic stroke (AIS) patient prognosis after mechanical thrombectomy (MT). METHODS: We analysed the characteristics of 144 AIS patients with MT treatment admitted to a university affiliated teaching hospital in Chengdu, Sichuan Province China, from January 2020 to December 2020. The modified Rankin Scale (mRS) score was used to assess outcomes 90-days after discharge. Exploratory analyses were undertaken using IBM SPSS Statistics (Version 26.0). RESULTS: At 90-days, 47.9% (n = 69) had a good prognosis (mRS ≤ 2) including 22.2% (n = 32) fully recovered patients. There were 5 (3.5%) deceased patients and 48.6% (n = 70) of patients had a poor prognosis (mRS ≥ 3). In univariate analysis, clinical prognosis correlated with the need for inpatient endotracheal intubation (p = 0.02), nasogastric tube (p < 0.001), indwelling urinary catheter (p < 0.001), central venous catheter (p = 0.03), health knowledge needs of pressure injury prevention (p = 0.03), National Institute of Health Stroke Scale (NIHSS) score (p < 0.001) and Activities of Daily Living (ADL) score (p < 0.001) at the time of discharge from hospital. The average hospitalization time of the 144 patients was 12[IQR, 9-25] days, and the average cost of hospitalization was $Y$21291.93 (SD 9165.01). CONCLUSION: Almost half of the surviving patients had a poor prognosis. In our country, this surgery and rehabilitation impose a significant financial burden that needs to be addressed. However, the longer length of hospital stay and higher costs at discharge may be contributing factors to worse outcomes. The outcomes of comprehensive nursing assessment of the patients, including nursing needs, activities of daily living, and neurological function, can predict their outcome. IMPACT STATEMENT: We recommend a comprehensive nursing assessment at discharge that predicts patient outcomes and can be used for subsequent targeted interventions. The prognosis of patients with acute ischaemic stroke after mechanical thrombectomy is poor, and the financial burden needs to be considered.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Trombectomia/efeitos adversos , Isquemia Encefálica/etiologia , Estudos de Coortes , Atividades Cotidianas , Resultado do Tratamento , Estudos Retrospectivos , Prognóstico
12.
Plants (Basel) ; 11(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36015468

RESUMO

Tartary buckwheat, a polygonaceae family plant, is rich in abundant flavonoids, high-quality protein, and well-balanced essential amino acids. This study aimed to investigate the effects of climatic variables on the quality of Tartary buckwheat. In this study, six distinct types of Tartary buckwheat collected from the Sichuan Basin, Western Sichuan Plateau, and Yunnan-Guizhou Plateau in southwest China were chosen to investigate the impact of climatic conditions from the grain-filling stage to the harvest stage on the concentration of flavonoids and expression of key enzyme genes involved the synthesis of flavonoids. Meteorological data of three producing areas were collected from the China Meteorological Network, mainly including maximum temperature (Tmax), minimum temperature (Tmin), diurnal temperature difference (Tdif), and light intensity. Then, the contents of rutin, kaempferol-3-O-rutin glycoside, quercetin, and kaempferol in 30 batches of Tartary buckwheat from 6 varieties including Chuanqiao No. 1, Chuanqiao No. 2, Xiqiao No. 1, Xiqiao No. 2, Miqiao No. 1 and Di ku were determined by ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Furthermore, the expression levels of phenylalanine ammonia lyase (PAL), 4-coumaric acid coenzyme A ligase (4CL), and anthocyanin synthase (ANS) in six kinds of Tartary buckwheat were detected by real-time polymerase chain reaction (PCR). The seed photos were processed by ImageJ processing software. The partial least squares method was used to analyze the correlation. As a result, light intensity can promote the accumulation of flavonoids and the expression of key enzyme genes. Miqiao No. 1, which grows in Liangshan Prefecture, Sichuan Province, has the highest light intensity and is the dominant variety with flavonoid content. More importantly, the expression levels of PAL and 4CL in the secondary metabolic pathway of flavonoids were positively correlated with the content of Tartary buckwheat flavonoids. Interestingly, the expression level of ANS was negatively correlated with the content of PAL, 4CL, and flavonoids. In addition, ANS is a key gene affecting the seed coat color of Tartary buckwheat. The higher the expression of ANS, the darker the seed coat color. These findings provide a theoretical basis and reference for the breeding of fine buckwheat varieties.

13.
Food Chem X ; 13: 100210, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35128383

RESUMO

While there is growing research interest in the effects of nutrition and exercise on delaying sarcopenia, the results are inconclusive and there is scarce information on regional patterns. This review evaluated the effects of the combination of protein supplementation and exercise on muscle strength, mass and physical performance, compared to exercise alone or with a placebo, in healthy older adults in Asian and non-Asian countries. Fourteen studies were included in the analysis, involving a total of 888 healthy older adults (>60 years). A significant increase in the lower-extremity strength was observed in the combined intervention group compared to the exercise group in Asian countries (SMD: 0.24, 95% CI [0.00, 0.47], p = 0.048, I2 = 0.0%). No statistical differences were found relating to upper-extremity strength, muscle mass and physical performance. Protein supplementation combined with exercise provides additional benefit on lower-extremity strength in healthy older adults with sarcopenia in Asian countries.

14.
ACS Appl Mater Interfaces ; 14(9): 11690-11698, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35213126

RESUMO

Two-dimensional (2D) multilayer Dion-Jacobson (DJ) phase organic inorganic hybrid perovskites (OIHPs) have attracted extensive research attention due to the high stability and excellent charge-transport properties in the optoelectronic field. However, the synthesis of 2D multilayer DJ OIHPs is still very challenging. Until now, only few multilayer DJ perovskites have been reported and most of them are based on volatile methylamine (MA) cations. Compared with MA-based OIHPs, the OIHPs constructed with formamidinium (FA) as perovskitizers not only improve the stability but also extend the light absorption range. Meanwhile, the introducing aromatic diamines as spacers could promote the electron-hole separation in such DJ hybrids. However, the DJ OIHP bulk single crystal constructed by using the advantages of FA as perovskitizers and aromatic diamines as spacers is still blank. Herein, we integrate the properties of organic cations and inorganic skeletons at a molecular-scale to construct a broadband-responsive 2D bilayer DJ perovskite (3AMPY)(FA)Pb2I7 [3AMPY = 3-(aminomethyl)pyridinium], which shows a fascinating detectivity from X-ray (5.23 × 104 µC Gyair-1 cm-2 at 200 V bias) and visible light (6 × 1012 jones at 637 nm) to the near-infrared region (2.6 × 109 jones at 780 nm). After an in-depth analysis of structure and optical properties, we found that the distortion degree of Pb-I-Pb bond angles between adjacent PbI6 octahedra plays a crucial role on optical properties; on the other hand, the interlayer spacer cations (3AMPY) and intralayer perovskitizers (FA) mutual participate in the contribution of the conduction band, making (3AMPY)(FA)Pb2I7 have a narrow optical band gap of 1.54 eV. Such a 2D perovskite material with a wide spectra response will be the preferred choice for photodetection under complex conditions.

15.
J Colloid Interface Sci ; 607(Pt 2): 1333-1342, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34583038

RESUMO

Li-rich disordered rock-salt cathode (DRX) materials with advantage of low cost, long cycle life, nature abundant resource and high power and energy density attracted a great deal of scholarly attention. However, the poor cycle stability and the unclear realization of cation and anion redox activity in low-cost element system have severely hindered the construction of high-performance DRX. Herein, a promising class of Ti-Mn based cathode materials Li1.25Mn0.25Nb0.25Ti0.25O2 and Li1.25Mn0.25Ti0.5O1.75F0.25 were designed and successfully synthesized to construct high energy density DRX and investigate the effect of fluorination on cation and anion redox activity. The results show that both fluoridized and unfluoridized DRX possess a similar structure (Fm-3 m), but distinctly different charge/discharge profiles. The fluoridized cathode shows high initial charge/discharge capacity of 317.3/283.9 mAh g-1, specific energy density of 1370.4/735.5 Wh kg-1 and stable capacity retention with a discharge capacity of 202.6 mAh g-1 after 20 cycles at 20 mA g-1. Combining relevant spectroscopic results and HRTEM images, we revealed that the excellent cyclability of Li1.25Mn0.25Ti0.5O1.75F0.25 is rooted in the weakened adverse effects of moderated oxygen redox and the reduced Jahn-Teller distortion effect resulting from Mn3+, endowing the fluoridized DRX with better structural stability and larger Mn2+/Mn4+ reservoir. The strategy of constructing low cost oxyfluoride and the understanding of the mechanism of fluorination induced cation and anion redox activity would provide reference for the development of high-performance DRX materials.

16.
Angew Chem Int Ed Engl ; 60(36): 20021-20026, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34223690

RESUMO

The introduction of chirality into organic-inorganic hybrid perovskites (OIHPs) is expected to achieve excellent photoelectric and nonlinear materials related to circular dichroism. Owing to the existence of asymmetric center and intrinsic chirality in the chiral OIHPs, the different efficiencies of second harmonic generation (SHG) signal occurs when the circularly polarized light (CPL) with different phases passes through the chiral crystal, which is defined as second harmonic generation circular dichroism (SHG-CD). Here, the SHG-CD effect is developed in bulk single crystals of chiral one-dimensional (1D) [(R/S)-3-aminopiperidine]PbI4 . It is the first time that CPL is distinguished using chirality-dependent SHG-CD effect in OIHPs bulk single crystals. Such SHG-CD technology extends the detection range to near infrared region (NIR). In this way, the anisotropy factor (gSHG-CD ) through SHG-CD signal is as high as 0.21.

17.
Front Plant Sci ; 12: 648277, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093611

RESUMO

Amygdalus pedunculata Pall [Rosaceae, Prunus, Prunus pedunculata (Pall.) Maxim.] belongs to the Rosaceae family and is resistant to cold and drought. Ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry and metabolomics were used to track the changes in bioactive metabolites during several stages of Amygdalus pedunculata Pall growth. A total of 827 different metabolites were detected, including 169 flavonoids, 68 organic acids, 35 terpenoids and 2 tannins. Flavonoid biosynthesis and flavone and flavonol biosynthesis were the main synthetic sources of flavonoids. Quercetin, isoquercitrin, and epicatechin as biomarkers related to growth and development were found. Quercetin connects the biosynthesis of flavonoids and the biosynthesis of flavones and flavonols. The contents of isoquercitrin and epicatechin increased uniformly during the whole growth process from the flowering stage to the fruit ripening stage, indicating that play key roles in the fruit growth and ripening stages of this plant. The tissue location and quantitative analysis of flavonoids in leaves at different stages were performed by confocal laser scanning microscopy. The flavonoids were mainly distributed in the palisade tissue and spongy tissue, indicating the need for protection of these sensitive tissues in particular. Through comprehensive and systematic analysis, the temporal distribution of flavonoids in the process of their leaves growth was determined. These results clarify the important role of flavonoids in the developmental process of Amygdalus pedunculata Pall.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...