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1.
ACS Appl Mater Interfaces ; 16(19): 25013-25024, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709947

RESUMEN

The magnetic alignment of molecules, which exploits the anisotropy of diamagnetic susceptibility, provides a clean and versatile approach to the structural manipulation of semiconducting polymers. Here, the magnetic-alignment dynamics of two molecular-weight (MW) batches of a diketopyrrolopyrrole (DPP)-based copolymer (PDVT-8) were investigated. Microstructural characterizations revealed that the magnetically aligned, high-MW (Mn = 53.7 kDa) PDVT-8 film exhibited a higher degree of backbone chain alignment and film crystallinity compared with the low-MW (Mn = 17.6 kDa) PDVT-8 film grown via the same magnetic alignment method. We found that as the MW increases, the degree of preaggregation of the polymer molecules in solution significantly increases and the aggregation mode changes from H-aggregation to J-aggregation through a cooperative assembly mechanism. These events improved the responsiveness of high-MW polymer molecules to magnetic fields. Field-effect transistors based on the magnetic aligned high-MW PDVT-8 films exhibited a 6.8-fold increase in hole mobility compared to the spin-coated films, along with a mobility anisotropy ratio of 12.6. This work establishes a significant correlation among chain aggregation behavior in solution, polymer film microstructures, magnetic responsiveness, and carrier transport performance in donor-acceptor polymer systems.

2.
Adv Mater ; : e2401788, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708900

RESUMEN

The power conversion efficiencies (PCEs) of polycrystalline perovskite (PVK) solar cells (SCs) (PC-PeSCs) have rapidly increased. However, PC-PeSCs are intrinsically unstable without encapsulation, and their efficiency drops during large-scale production; these problems hinder the commercial viability of PeSCs. Stability can be increased by using colloidal PVK nanocrystals (c-PeNCs), which have high surface strains, low defect density, and exceptional crystal quality. The use of c-PeNCs separates the crystallization process from the film formation process, which is preponderant in large-scale fabrication. Consequently, the use of c-PeNCs has substantial potential to overcome challenges encountered when fabricating PC-PeSCs. Research on colloidal nanocrystal-based PVK SCs (NC-PeSCs) has increased their PCEs to a level greater than those of other quantum-dot SCs, but has not reached the PCEs of PC-PeSCs; this inferiority significantly impedes widespread application of NC-PeSCs. This review first introduces the distinctive properties of c-PeNCs, then the strategies that have been used to achieve high-efficiency NC-PeSCs. Then it discusses in detail the persisting challenges in this domain. Specifically, the major challenges and solutions for NC-PeSCs related to low short-circuit current density Jsc are covered. Last, the article presents a perspective on future research directions and potential applications in the realm of NC-PeSCs.

3.
Nat Plants ; 10(5): 736-742, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38724696

RESUMEN

Symbiotic nitrogen fixation in legume nodules requires substantial energy investment from host plants, and soybean (Glycine max (L.) supernodulation mutants show stunting and yield penalties due to overconsumption of carbon sources. We obtained soybean mutants differing in their nodulation ability, among which rhizobially induced cle1a/2a (ric1a/2a) has a moderate increase in nodule number, balanced carbon allocation, and enhanced carbon and nitrogen acquisition. In multi-year and multi-site field trials in China, two ric1a/2a lines had improved grain yield, protein content and sustained oil content, demonstrating that gene editing towards optimal nodulation improves soybean yield and quality.


Asunto(s)
Glycine max , Nodulación de la Raíz de la Planta , Glycine max/genética , Glycine max/metabolismo , Glycine max/microbiología , Nodulación de la Raíz de la Planta/genética , Nódulos de las Raíces de las Plantas/metabolismo , Nódulos de las Raíces de las Plantas/genética , Nódulos de las Raíces de las Plantas/microbiología , Simbiosis , Fijación del Nitrógeno/genética , Edición Génica , Mutación , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Soja/genética , Proteínas de Soja/metabolismo
4.
Infect Drug Resist ; 17: 1751-1762, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38736437

RESUMEN

Purpose: This study was to identify and analyze the pathogen responsible for food poisoning in a tourist group traveling from Macao to Zhuhai. Patients and Methods: Samples were obtained from 27 patients of 96 cases, as well as samples of contaminated food in Macau. The collected samples were subjected to serological identification, drug sensitivity analysis, drug resistance gene identification, virulence factor analysis, and tracing. Results: Twenty-six isolates and the salad isolate were S. enteritidis ST11. Isolates from patients were exhibited significant resistance to Penicillin AMP (Ampicillin) and quinolones NAL (Nalidixic acid). Among these isolates, 21 strains were resistant to two or more antibiotics, indicating the multi-drug resistance (MDR). Genomic characteristics and phylogenetic analysis were performed on 9 of the isolates using whole genome sequencing (WGS). The analysis revealed that the resistance to AMP and NAL was primarily caused by a gryA mutation D87Y (9/9, 100%), and the presence of beta-lactam resistance genes blaOXA-1 (1/9, 11.11%), blaTEM-141 (1/9, 11.11%), and blaTEM-1B (8/9, 88.89%). It was also found a strains isolated from patients had two resistance genes to quinolones or beta-lactam drugs (1/8, 12.5%), respectively. The strains were found to possess 165 virulence genes, one adherence class virulence factor, one invasion class virulence factor and various pathogenicity islands, including SPI-1, SPI-2, SPI-3, SPI-4, SPI-5, SPI-9, SPI-10, SPI-13, SPI-14, SPI-15, SGI 1, CS54_island, and C63PI-1. Additionally, the virulence plasmids were detected, including IncFIB(s)-IncFII(s)-IncX1 (55.56%), IncFIB(s)-IncFII(s) (33.33%), and IncFIB(s)-IncFII(s)-IncHI2-IncHI2A (11.11%). PFGE (Pulsed Field Gel Electrophoresis) and phylogenetic tree analysis revealed a high degree of similarity between Salmonella isolates from patients and food samples from Macao. Conclusion: This study identified Salmonella enterica ST11 as the cause of the food poisoning outbreak. The findings highlight the importance of phenotypic characterization and next-generation sequencing (NGS) tools in epidemiological studies and emphasize the potential risk of a new emerging multi-antibiotic ST11 clone for S. enteritidis.

5.
J Colloid Interface Sci ; 665: 863-870, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38564950

RESUMEN

NiFe-(oxy)hydroxides are the most active transition metal oxide electrocatalysts for oxygen evolution reaction (OER) under the alkaline media. Herein, we controllably manipulated oxygen vacancy (VO)-tunable NiFe-(oxy) hydroxides that their OER performances possessed a volcano-type relationship with VO concentration, positively-correlated with Ni3+/Ni2+ ratio. Theoretical simulations further unearthed the enhanced activation and dissociation of H2O by the inserting of VO. As a result, the optimal sample featuring the Ni3+/Ni2+ ratio of 30.3 % and VO of 23.8 % exhibited the overpotential of 243 mV at the current density of 100 mA cm-2, simultaneously lasting 120 h durability without any attenuation, exceding the most reported NiFe-(oxy)hydroxides. This work offers an innovative view to understand the OER performance using hypervalent Ni ratio induced by VO defects.

6.
J Ovarian Res ; 17(1): 74, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570862

RESUMEN

OBJECTIVE: To comprehensively evaluate the effect of low birth weight on premature ovarian insufficiency. METHODS: We performed a systematic review of the literature by searching MEDLINE, EMBASE, Web of Science, Scopus, Wanfang and CNKI up to August 2023. All cohort and case-control studies that included birth weight as an exposure and premature ovarian insufficiency as an outcome were included in the analysis. Data were combined using inverse-variance weighted meta-analysis with fixed and random effects models and between-study heterogeneity evaluated. We evaluated risk of bias using the Newcastle Ottawa Scale and using Egger's method to test publication bias. All statistical analyses were performed with the use of R software. RESULTS: Five articles were included in the review. A total of 2,248,594 women were included, including 21,813 (1%) cases of premature ovarian insufficiency, 150,743 cases of low birth weight, and 220,703 cases of macrosomia. We found strong evidence that changed the results of the previous review that low birth weight is associated with an increased risk of premature ovarian insufficiency (OR = 1.15, 95%CI 1.09-1.22) in adulthood compared with normal birth weight. No effect of macrosomia on premature ovarian insufficiency was found. CONCLUSIONS: Our meta-analysis showed strong evidence of an association between low birth weight and premature ovarian insufficiency. We should reduce the occurrence of low birth weight by various methods to avoid the occurrence of premature ovarian insufficiency.


Asunto(s)
Menopausia Prematura , Insuficiencia Ovárica Primaria , Recién Nacido , Femenino , Humanos , Peso al Nacer , Macrosomía Fetal , Recién Nacido de Bajo Peso
7.
J Fungi (Basel) ; 10(3)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38535228

RESUMEN

The species of Gymnopilus (Hymenogastraceae, Agricales) are commonly recognized as wood-decaying fungi. Certain members of this genus have been identified as psilocybin-producing mushrooms. Gymnopilus exhibits a diverse range and has a global distribution. In this study, a total of seventy-eight specimens were gathered from ten provinces in China. A comprehensive molecular phylogenetic analysis was conducted, employing gene sequences including ITS, nrLSU, nrSSU, rpb1, rpb2, and tef1-α. Additionally, morphological examinations were also carried out. The phylogenetic topology of Gymnopilus from this study generally agreed with previous studies and facilitated the identification of all those specimens. As a result, eleven species, including five newly discovered ones named Gy. gyirongensis, Gy. variisporus, Gy. tomentosiceps, Gy. tenuibasidialis, and Gy. aurantipileatus, were recognized. Significantly, four of the five newly identified species are native to the Xizang Autonomous Region, emphasizing their specialization in this distinctive habitat. This research contributes to our comprehension of Gymnopilus diversity and lays the groundwork for the conservation and sustainable utilization of Gymnopilus resources.

8.
Water Res ; 254: 121388, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38430759

RESUMEN

The periodate (PI)-based advanced oxidation process is valued for environmental remediation, but current activation methods involve high costs, secondary contamination risks, and limited applicability due to external energy inputs (e.g., UV), catalyst incorporation (e.g., Fe2+), or environmental modifications (e.g., freezing). In this work, novel bioelectric activation of PI using the electrons generated by electroactive bacteria was developed and investigated for rapid removal of carbamazepine (CBZ), achieving 100 %, 100 %, and 76 % removal efficiency for 4.22 µM of CBZ in 20 min at pH 2, 120 min at pH 6.4, and HRT of 30 min at pH 8.5, respectively, with a 1 mM PI dose and without an input voltage. It was deduced that electrons derived from bacteria could directly activate PI using Ti mesh electrodes and generate •IO3 via single electron transfer under strongly acidic conditions (e.g., pH 2). Nevertheless, under weak alkaline conditions (e.g., pH 8.5), biogenic electrons indirectly activated PI by generating OH-via 4e-reduction at the Ti mesh cathode, resulting in the formation of •O2- and 1O2. In addition to the metal cathode, a carbon-based cathode finely modulates the 2e-reduction, yielding H2O2 and activating PI to mainly form •OH. Moreover, primarily non-toxic IO3- was produced during treatment, while no detectable reactive iodine species (HOI, I2, and I3-) were observed. Furthermore, the bioelectric activation of PI demonstrated its capability to remove various micropollutants present in secondary-treated municipal wastewater, showcasing its broad-spectrum degradation ability. This study introduces a novel, cost-effective, and environmentally friendly PI activation technique with promising applicability for micropollutant elimination in water treatment.


Asunto(s)
Peróxido de Hidrógeno , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Aguas Residuales , Ácido Peryódico , Oxidación-Reducción , Carbamazepina
9.
J Am Chem Soc ; 146(9): 5834-5842, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38277793

RESUMEN

Electrochemical conversion of CH4 to easily transportable and value-added liquid fuels is highly attractive for energy-efficient CH4 utilization, but it is challenging due to the low reactivity and solubility of CH4 in the electrolyte. Herein, we report a high-pressure electro-Fenton (HPEF) strategy to establish a hetero-homogeneous process for the electrocatalytic conversion of CH4 by O2 at room temperature. In combination with elevation of reactant pressure to accelerate reaction kinetics, it delivers an unprecedented HCOOH productivity of 11.5 mmol h-1 gFe-1 with 220 times enhancement compared to that under ambient pressure. Remarkably, an HCOOH Faradic efficiency of 81.4% can be achieved with an ultralow cathodic overpotential of 0.38 V. The elevated pressure not only promotes the electrocatalytic reduction of O2 to H2O2 but also increases the reaction collision probability between CH4 and •OH, which is in situ generated from the Fe2+-facilitated decomposition of H2O2.

10.
Neural Netw ; 172: 106089, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38181617

RESUMEN

This paper studies the fixed-time synchronization (FDTS) of complex-valued neural networks (CVNNs) based on quantized intermittent control (QIC) and applies it to image protection and 3D point cloud information protection. A new controller was designed which achieved FDTS of the CVNNs, with the estimation of the convergence time not dependent on the initial state. Our approach divides the neural network into two real-valued systems and then combines the framework of the Lyapunov method to give criteria for FDTS. Applying synchronization to image protection, the image will be encrypted with a drive system sequence and decrypted with a response system sequence. The quality of image encryption and decryption depends on the synchronization error. Meanwhile, the depth image of the object is encrypted and then the 3D point cloud is reconstructed based on the decrypted depth image. This means that the 3D point cloud information is protected. Finally, simulation examples verify the efficacy of the controller and the synchronization criterion, giving results for applications in image protection and 3D point cloud information protection.


Asunto(s)
Redes Neurales de la Computación , Factores de Tiempo , Simulación por Computador
11.
J Chem Inf Model ; 64(2): 327-339, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38197612

RESUMEN

Catalyst screening is a critical step in the discovery and development of heterogeneous catalysts, which are vital for a wide range of chemical processes. In recent years, computational catalyst screening, primarily through density functional theory (DFT), has gained significant attention as a method for identifying promising catalysts. However, the computation of adsorption energies for all likely chemical intermediates present in complex surface chemistries is computationally intensive and costly due to the expensive nature of these calculations and the intrinsic idiosyncrasies of the methods or data sets used. This study introduces a novel machine learning (ML) method to learn adsorption energies from multiple DFT functionals by using invariant molecular representations (IMRs). To do this, we first extract molecular fingerprints for the reaction intermediates and later use a Siamese-neural-network-based training strategy to learn invariant molecular representations or the IMR across all available functionals. Our Siamese network-based representations demonstrate superior performance in predicting adsorption energies compared with other molecular representations. Notably, when considering mean absolute values of adsorption energies as 0.43 eV (PBE-D3), 0.46 eV (BEEF-vdW), 0.81 eV (RPBE), and 0.37 eV (scan+rVV10), our IMR method has achieved the lowest mean absolute errors (MAEs) of 0.18 0.10, 0.16, and 0.18 eV, respectively. These results emphasize the superior predictive capacity of our Siamese network-based representations. The empirical findings in this study illuminate the efficacy, robustness, and dependability of our proposed ML paradigm in predicting adsorption energies, specifically for propane dehydrogenation on a platinum catalyst surface.


Asunto(s)
Aprendizaje Automático , Redes Neurales de la Computación , Bovinos , Animales , Catálisis , Adsorción
12.
Mol Plant ; 17(1): 199-213, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38018035

RESUMEN

Protein phosphorylation regulates a variety of important cellular and physiological processes in plants. In-depth profiling of plant phosphoproteomes has been more technically challenging than that of animal phosphoproteomes. This is largely due to the need to improve protein extraction efficiency from plant cells, which have a dense cell wall, and to minimize sample loss resulting from the stringent sample clean-up steps required for the removal of a large amount of biomolecules interfering with phosphopeptide purification and mass spectrometry analysis. To this end, we developed a method with a streamlined workflow for highly efficient purification of phosphopeptides from tissues of various green organisms including Arabidopsis, rice, tomato, and Chlamydomonas reinhardtii, enabling in-depth identification with high quantitative reproducibility of about 11 000 phosphosites, the greatest depth achieved so far with single liquid chromatography-mass spectrometry (LC-MS) runs operated in a data-dependent acquisition (DDA) mode. The mainstay features of the method are the minimal sample loss achieved through elimination of sample clean-up before protease digestion and of desalting before phosphopeptide enrichment and hence the dramatic increases of time- and cost-effectiveness. The method, named GreenPhos, combined with single-shot LC-MS, enabled in-depth quantitative identification of Arabidopsis phosphoproteins, including differentially phosphorylated spliceosomal proteins, at multiple time points during salt stress and a number of kinase substrate motifs. GreenPhos is expected to serve as a universal method for purification of plant phosphopeptides, which, if samples are further fractionated and analyzed by multiple LC-MS runs, could enable measurement of plant phosphoproteomes with an unprecedented depth using a given mass spectrometry technology.


Asunto(s)
Arabidopsis , Animales , Arabidopsis/metabolismo , Fosfopéptidos/análisis , Fosfopéptidos/química , Fosfopéptidos/metabolismo , Espectrometría de Masas en Tándem/métodos , Reproducibilidad de los Resultados , Fosforilación , Fosfoproteínas/metabolismo
13.
Inorg Chem ; 62(51): 21461-21469, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38041798

RESUMEN

The development of high-efficiency oxygen evolution reaction (OER) electrocatalysts for the production and conversion of clean energy is paramount yet also full of challenges. Herein, we proposed a simple and universal method to precisely fabricate the hierarchically structured CuO/TMOs loaded on Cu foil (CuO/TMOs/CF) (TMO represents Mn3O4, NiO, CoO, and CuO) nanorod-array electrodes as a highly active and stable OER electrocatalyst, employing Cu(OH)2/CF as a self-sacrificing template by the subsequent H2O2-induced chemical deposition (HiCD) and pyrolysis process. Taking CuO/Mn3O4/CF as an example, we systematically investigated its structure-performance relationship via experimental and theoretical explorations. The enhanced OER activity can be ascribed to the rational design of the nanoarray with multiple synergistic effects of abundant active sites, excellent electronic conductivity of the metallic Cu foil substrate, strong interface charge transfer, and quasi-superhydrophilic/superaerophobic property. Consequently, the optimal CuO/Mn3O4/CF presents an overpotential of 293 mV to achieve a current density of 20 mA cm-2 in 1.0 M KOH media, comparable to that of commercial RuO2 (282 mV), delivering excellent durability by the electrolysis of water at a potential of around 1.60 V [vs reversible hydrogen electrode (RHE)] without evident degeneration. This work might offer a feasible scheme for developing a hybrid nanoarray OER electrocatalyst via regulating electron transportation and mass transfer.

14.
Sci Adv ; 9(43): eadi8446, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37878698

RESUMEN

Diatoms rely on fucoxanthin chlorophyll a/c-binding proteins (FCPs) for their great success in oceans, which have a great diversity in their pigment, protein compositions, and subunit organizations. We report a unique structure of photosystem II (PSII)-FCPII supercomplex from Thalassiosira pseudonana at 2.68-Å resolution by cryo-electron microscopy. FCPIIs within this PSII-FCPII supercomplex exist in dimers and monomers, and a homodimer and a heterodimer were found to bind to a PSII core. The FCPII homodimer is formed by Lhcf7 and associates with PSII through an Lhcx family antenna Lhcx6_1, whereas the heterodimer is formed by Lhcf6 and Lhcf11 and connects to the core together with an Lhcf5 monomer through Lhca2 monomer. An extended pigment network consisting of diatoxanthins, diadinoxanthins, fucoxanthins, and chlorophylls a/c is revealed, which functions in efficient light harvesting, energy transfer, and dissipation. These results provide a structural basis for revealing the energy transfer and dissipation mechanisms and also for the structural diversity of FCP antennas in diatoms.


Asunto(s)
Diatomeas , Complejo de Proteína del Fotosistema II , Complejo de Proteína del Fotosistema II/química , Clorofila A/metabolismo , Diatomeas/química , Microscopía por Crioelectrón , Proteínas de Unión a Clorofila/química , Proteínas de Unión a Clorofila/metabolismo , Polímeros/metabolismo
15.
Front Endocrinol (Lausanne) ; 14: 1238090, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900148

RESUMEN

Objective: Type 2 diabetes mellitus (T2DM) is an endocrine-related disease with an increasing incidence worldwide. Male sexual dysfunction is common in diabetic patients. Therefore, we designed a Mendelian randomization (MR) study to investigate the association of type 2 diabetes and 3 glycemic traits with testosterone levels. Methods: Uncorrelated single nucleotide polymorphisms (SNPs) associated with T2DM (N = 228), fasting insulin (N = 38), fasting glucose (N = 71), and HbA1c (N = 75) at the genome-wide significance were selected as instrument variables. Genetic associations with testosterone levels (total testosterone, TT, bioavailable testosterone, BT, and sex hormone-binding globulin, SHBG) were obtained from the UK Biobank studies and other large consortia. Two-sample MR analysis was used to minimize the bias caused by confounding factors and response causality. Multivariable MR analysis was performed using Body mass index (BMI), Triglycerides (TG), LDL cholesterol (LDL), and adiponectin to adjust for the effects of potential confounders. Results: Type 2 diabetes mellitus was associated with the decrease of total testosterone (ß: -0.021,95%CI: -0.032, -0.010, p<0.001) and sex hormone binding globulin (ß: -0.048,95%CI: -0.065, -0.031, p<0.001). In males, total testosterone (ß: 0.058, 95% CI: 0.088, 0.028, p < 0.001) decreased. In females, it was associated with an increase in bioavailable testosterone (ß: 0.077,95%CI: 0.058,0.096, p<0.001). Each unit (pmol/L) increase in fasting insulin was associated with 0.283nmol/L decrease in sex hormone-binding globulin (95%CI: -0.464, -0.102, p=0.002) and 0.260nmol/L increase in bioavailable testosterone (95%CI: -0.464, -0.102, p= 0.002). In males, sex hormone binding globulin decreased by 0.507nmol/L (95%CI: -0.960, -0.054, p= 0.028) and bioavailable testosterone increased by 0.216nmol/L (95%CI: 0.087,0.344, p= 0.001). In females, sex hormone binding globulin decreased by 0.714 nmol/L (95%CI: -1.093, -0.335, p<0.001) and bioavailable testosterone increased by 0.467nmol/L (95%CI: 0.286,0.648, p<0.001). Each unit (%) increase in HbA1c was associated with 0.060nmol/L decrease in sex hormone-binding globulin (95%CI: -0.113, -0.007, p= 0.026). In males, total testosterone decreased by 0.171nmol/L (95%CI: -0.288, -0.053, p=0.005) and sex hormone binding globulin decreased by 0.206nmol/L (95%CI: -0.340, -0.072, p=0.003). Total testosterone increased by 0.122nmol/L (95%CI: 0.012,0.233, p=0.029) and bioavailable testosterone increased by 0.163nmol/L (95%CI: 0.042,0.285, p=0.008) in females. Conclusions: Using MR Analysis, we found independent effects of type 2 diabetes, fasting insulin, and HbA1c on total testosterone and sex hormone-binding globulin after maximum exclusion of the effects of obesity, BMI, TG, LDL and Adiponectin.


Asunto(s)
Diabetes Mellitus Tipo 2 , Femenino , Humanos , Masculino , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/epidemiología , Globulina de Unión a Hormona Sexual/metabolismo , Hemoglobina Glucada , Adiponectina/metabolismo , Análisis de la Aleatorización Mendeliana , Testosterona , Insulina/metabolismo , Triglicéridos
16.
Nat Commun ; 14(1): 4207, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-37452043

RESUMEN

While photosynthesis transforms sunlight energy into sugar, aerobic and anaerobic respiration (fermentation) catabolizes sugars to fuel cellular activities. These processes take place within one cell across several compartments, however it remains largely unexplored how they interact with one another. Here we report that the weak acids produced during fermentation down-regulate both photosynthesis and aerobic respiration. This effect is mechanistically explained with an "ion trapping" model, in which the lipid bilayer selectively traps protons that effectively acidify subcellular compartments with smaller buffer capacities - such as the thylakoid lumen. Physiologically, we propose that under certain conditions, e.g., dim light at dawn, tuning down the photosynthetic light reaction could mitigate the pressure on its electron transport chains, while suppression of respiration could accelerate the net oxygen evolution, thus speeding up the recovery from hypoxia. Since we show that this effect is conserved across photosynthetic phyla, these results indicate that fermentation metabolites exert widespread feedback control over photosynthesis and aerobic respiration. This likely allows algae to better cope with changing environmental conditions.


Asunto(s)
Respiración de la Célula , Fotosíntesis , Anaerobiosis , Fermentación , Respiración
17.
Adv Mater ; 35(39): e2304533, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37390092

RESUMEN

The small nanoparticle size and long-chain ligands in colloidal metal halide perovskite quantum dots (PeQDs) cause charge confinement, which impedes exciton dissociation and carrier extraction in PeQD solar cells, so they have low short-circuit current density Jsc , which impedes further increases in their power conversion efficiency (PCE). Here, a re-assembling process (RP) is developed for perovskite nanocrystalline (PeNC) films made of colloidal perovskite nanocrystals to increase Jsc in PeNC solar cells. The RP of PeNC films increases their crystallite size and eliminates long-chain ligands, and thereby overcomes the charge confinement in PeNC films. These changes facilitate exciton dissociation and increase carrier extraction in PeNC solar cells. By use of this method, the gradient-bandgap PeNC solar cells achieve a Jsc = 19.30 mA cm-2 without compromising the photovoltage, and yield a high PCE of 16.46% with negligible hysteresis and good stability. This work provides a new strategy to process PeNC films and pave the way for high performance PeNC optoelectronic devices.

18.
ISA Trans ; 135: 290-298, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37032566

RESUMEN

In this paper, the bipartite synchronization of signed Lur'e network is studied under intermittent control, where the communication relationship of these adjacent nodes in the network can be either cooperative or competitive. Assuming that the network is structurally balanced, bipartite synchronization can be reached with some conditions and coordinate transform criterion. Then, Based on Lyapunov stability theory, some important norms are established. Ultimately, the simulation results can illustrate validness of theoretical analysis.

19.
Nat Commun ; 14(1): 2292, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085529

RESUMEN

The initial signals governing sex determination vary widely among insects. Here we show that Armigeres subalbatus M factor (AsuMf), a male-specific duplication of an autosomal gene of the Drosophila behaviour/human splicing (DBHS) gene family, is the potential primary signal for sex determination in the human filariasis vector mosquito, Ar. subalbatus. Our results show that AsuMf satisfies two fundamental requirements of an M factor: male-specific expression and early embryonic expression. Ablations of AsuMf result in a shift from male- to female-specific splicing of doublesex and fruitless, leading to feminization of males both in morphology and general transcription profile. These data support the conclusion that AsuMf is essential for male development in Ar. subalbatus and reveal a male-determining factor that is derived from duplication and subsequent neofunctionalization of a member of the conserved DBHS family.


Asunto(s)
Culicidae , Filariasis , Animales , Femenino , Humanos , Masculino , Culicidae/genética , Drosophila , Familia , Mosquitos Vectores/genética , Diferenciación Sexual
20.
J Fungi (Basel) ; 9(3)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36983551

RESUMEN

The species of Agrocybe (Strophariaceae, Agaricales, Agaricomycetes) are saprophytic and widely distributed in temperate regions. In this study, a new species named Agrocybe striatipes from China is described, which has been successfully cultivated in China recently. The phenotypic characteristics examination and molecular phylogenetic analyses using multilocus data (ITS and nrLSU) both support it as a new species in the genus Agrocybe. Moreover, nutritional ingredient analysis showed that the fruiting body of A. striatipes was rich in seventeen amino acids, including eight essential amino acids, in addition to high levels of calcium (78.5 mg/kg) and vitamin D (44.1 µg/100g). The following analysis of the heavy metal contents of the fruiting bodies show that it does not contain lead, cadmium, arsenic, mercury, and other heavy metal elements. In the crude extract of the mushroom, the nutrients in the aqueous phase are amino acids and oligosaccharides, and the active substances in the ethyl acetate layer are sterols, which have a variety of pharmacological effects. In conclusion, A. striatipes is not only a new species but also has highly application values as a cultivated edible mushroom in nutrition and health.

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