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1.
Trends Genet ; 38(10): 1048-1061, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35688654

RESUMO

Cellular lineage determination is controlled by combinations of lineage-selective transcription factors (TFs) and associated coregulators that bind to cis-regulatory elements in DNA and regulate gene expression. The ability of these factors to regulate transcription is determined not only by their cooperativity, but also by biochemical and structural properties of the chromatin, sculpting higher-order genome organization. Here, we review recent advances in the understanding of the interplay between chromatin topology and transcription. Studies from many different fields, including adipocyte lineage determination, indicate that lineage determination and differentiation are dependent on elaborate crosstalk between cis-regulatory elements, leading to the formation of transcriptional hubs. Chromatin topology appears to provide a dynamic and supportive, rather than a deterministic, scaffold for this crosstalk.


Assuntos
Cromatina , Elementos Facilitadores Genéticos , Linhagem da Célula/genética , Cromatina/genética , DNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Nano Lett ; 24(39): 12140-12147, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39119948

RESUMO

N-Doped carbon sheets based on edge engineering provide more opportunities for improving oxygen reduction reaction (ORR) active sites. However, with regard to the correlation between porous structural configurations and performances, it remains underexplored. Herein, a silica-assisted localized etching method was employed to create two-dimensional mesoporous carbon materials with customizable pore structures, abundant edge sites, and nitrogen functionalities. The mesoporous carbon exhibited superior electrocatalytic performance for the ORR compared to that of a 20 wt % Pt/C catalyst, achieving a half-wave potential of 0.88 V versus RHE, situating them in the leading level of the reported carbon electrocatalysts. Experimental data suggest that the edge graphitic nitrogen sites played a crucial role in the ORR process. The three-dimensional interconnected pores provided a high density of active sites for the ORR and facilitated the efficient transport of electrons. These unique properties make the carbon sheets a promising candidate for highly efficient air cathodes in rechargeable Zn-air batteries.

3.
Small ; 20(6): e2306275, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37775936

RESUMO

Vanadium trioxide (V6 O13 ) cathode has recently aroused intensive interest for aqueous zinc-ion batteries (AZIBs) due to their structural and electrochemical diversities. However, it undergoes sluggish reaction kinetics and significant capacity decay during prolonged cycling. Herein, an oxygen-vacancy-reinforced heterojunction in V6 O13- x /reduced graphene oxide (rGO) cathode is designed through electrostatic assembly and annealing strategy. The abundant oxygen vacancies existing in V6 O13- x weaken the electrostatic attraction with the inserted Zn2+ ; the external electric field constructed by the heterointerfaces between V6 O13- x and rGO provides additional built-in driving force for Zn2+ migration; the oxygen-vacancy-enriched V6 O13- x highly dispersed on rGO fabricates the interconnected conductive network, which achieves rapid Zn2+ migration from heterointerfaces to lattice. Consequently, the obtained 2D heterostructure exhibits a remarkable capacity of 424.5 mAh g-1 at 0.1 A g-1 , and a stable capacity retention (96% after 5800 cycles) at the fast discharge rate of 10 A g-1 . Besides, a flexible pouch-type AZIB with real-life practicability is fabricated, which can successfully power commercial products, and maintain stable zinc-ion storage performances even under bending, heavy strikes, and pressure condition. A series of quantitative investigation of pouch batteries demonstrates the possibility of pushing pouch-type AZIBs to realistic energy storage market.

4.
Small ; 20(16): e2306750, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38044278

RESUMO

Thermal interface materials (TIMs) are in desperate desire with the development of the modern electronic industry. An excellent TIM needs desired comprehensive properties including but not limited to high thermal conductivity, low Yong's modulus, lightweight, as well as low price. However, as is typically the case, those properties are naturally contradictory. To tackle such dilemmas, a strategy of construction high-performance TIM inspired by alveoli is proposed. The material design includes the self-alignment of graphite into 3D interconnected thermally conductive networks by polydimethylsiloxane beads (PBs) -the alveoli; and a small amount of liquid metal (LM) - capillary networks bridging the PBs and graphite network. Through the delicate structural regulation and the synergistic effect of the LM and solid graphite filler, superb thermal conductivity (9.98 ± 0.34 W m-1 K-1) can be achieved. The light emitting diode (LED) application and their performance in the central processing unit (CPU) heat dispersion manifest the TIM developed in the work has stable thermal conductivity for long-term applications. The thermally conductive, soft, and lightweight composites are believed to be high-performance silicone bases TIMs for advanced electronics.

5.
Small ; : e2406007, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126235

RESUMO

The uneven formation of lithium dendrites during electroplating/stripping leads to a decrease in the utilization of active lithium, resulting in poor cycling stability and posing safety hazards to the battery. Herein, introducing a 3D continuously interconnected zirconium-based metal-organic framework (MOF808) network into a polyethylene oxide polymer matrix establishes a synergistic mechanism for lithium dendrite inhibition. The 3D MOF808 network maintains its large pore structure, facilitating increased lithium salt accommodation, and expands anion adsorption at unsaturated metal sites through its diverse large-space cage structure, thereby promoting the flow of Li+. Infrared-Raman and synchrotron small-angle X-ray scattering results demonstrate that the transport behavior of lithium salt ion clusters at the MOF/polymer interface verifies the increased local Li+ flux concentration, thereby raising the mobility number of Li+ to 0.42 and ensuring uniform Li+ flux distribution, leading to dendrite-free and homogeneous Li+ deposition. Furthermore, nanoindentation tests reveal that the high modulus and elastic recovery of MOF-based polymer electrolytes contribute to forming a robust, dendrite-resistant interface. Consequently, in symmetric battery systems, the system exhibits minimal overpotential, merely 35 mV, while maintaining stable cycling for over 1800 h, achieving low-overpotential lithium deposition. Moreover, it retains redox stability under high voltages up to 5.3 V.

6.
Small ; 20(15): e2307743, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009525

RESUMO

Herein, a series of imine-linked covalent organic frameworks (COFs) are developed with advanced ordered mesoporous hollow spherical nanomorphology and ultra-large mesopores (4.6 nm in size), named OMHS-COF-M (M = H, Co, and Ni). The ordered mesoporous hollow spherical nanomorphology is revealed to be formed via an Ostwald ripening mechanism based on a one-step self-templated strategy. Encouraged by its unique structural features and outstanding photoelectrical property, the OMHS-COF-Co material is applied as the photocatalyst for CO2-to-CO reduction. Remarkably, it delivers an impressive CO production rate as high as 15 874 µmol g-1 h-1, a large selectivity of 92.4%, and a preeminent cycling stability. From in/ex situ experiments and density functional theory (DFT) calculations, the excellent CO2 photoreduction performance is ascribed to the desirable cooperation of unique ordered mesoporous hollow spherical host and abundant isolated Co active sites, enhancing CO2 activation, and improving electron transfer kinetics as well as reducing the energy barriers for intermediates *COOH generation and CO desorption.

7.
Mol Pharm ; 21(4): 1900-1918, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38469754

RESUMO

The use of amorphous solid dispersions (ASDs) in commercial drug products has increased in recent years due to the large number of poorly soluble drugs in the pharmaceutical pipeline. However, the release behavior of ASDs is complex and remains not well understood. Often, the drug release from ASDs is rapid and complete at lower drug loadings (DLs) but becomes slow and incomplete at higher DLs. The DL where release becomes hindered is termed the limit of congruency (LoC). Currently, there are no approaches to predict the LoC. However, recent findings show that one potential cause leading to the LoC is a change in phase morphology after water-induced phase separation at the ASD/solution interface. In this study, the phase behavior of ASDs in contact with aqueous solutions was described thermodynamically by constructing experimental and computational ternary phase diagrams, and these were used to predict morphology changes and ultimately the LoC. Experimental ternary phase diagrams were obtained by equilibrating ASD/water mixtures over time. Computational ternary phase diagrams were obtained by Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT). The morphology of the hydrophobic phase was studied with fluorescence confocal microscopy. It was demonstrated that critical point (plait point) composition approximately corresponded to the ASD DL, where the hydrophobic phase, formed during phase separation, became interconnected and hindered ASD release. This work provides mechanistic insights into the ASD release behavior and highlights the potential of in silico ASD design using phase diagrams.


Assuntos
Água , Solubilidade , Liberação Controlada de Fármacos , Água/química , Interações Hidrofóbicas e Hidrofílicas , Composição de Medicamentos
8.
Environ Sci Technol ; 58(8): 3812-3822, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38358300

RESUMO

Fog harvesting is considered a promising freshwater collection strategy for overcoming water scarcity, because of its environmental friendliness and strong sustainability. Typically, fogging occurs briefly at night and in the early morning in most arid and semiarid regions. However, studies on water collection from short-term fog are scarce. Herein, we developed a patterned surface with highly hydrophilic interconnected microchannels on a superhydrophobic surface to improve droplet convergence driven by the Young-Laplace pressure difference. With a rationally designed surface structure, the optimized water collection rate from mild fog could reach up to 67.31 g m-2 h-1 (6.731 mg cm-2 h-1) in 6 h; this value was over 130% higher than that observed on the pristine surface. The patterned surface with interconnected microchannels significantly shortened the startup time, which was counted from the fog contact to the first droplet falling from the fog-harvesting surface. The patterned surface was also facilely prepared via a controllable strategy combining laser ablation and chemical vapor deposition. The results obtained in outdoor environments indicate that the rationally designed surface has the potential for short-term fog harvesting. This work can be considered as a meaningful attempt to address the practical issues encountered in fog-harvesting research.


Assuntos
Água Doce , Água , Gases , Pressão , Tempo (Meteorologia) , Interações Hidrofóbicas e Hidrofílicas
9.
Mikrochim Acta ; 191(9): 552, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167265

RESUMO

N-doped hollow carbon spheres (NHCSs) with different shell thicknesses are constructed using various amounts of SiO2 precursor. An interconnected framework with diminished wall thickness ensures an efficient and continuous electron transport which helps to enhance the performance of NHCS. Improvement of the electrocatalytic performance was shown in the determination of antibiotic drug chloramphenicol (CAP) due to the unique hollow thin shell morphology, ample defect sites, accessible surface area, higher surface-to-volume ratio and an synergistic effect. Boosted electrocatalytic activity of 1.5 N-doped HCS (1.5 NHCS) was applied to detect CAP with a linear range and detection limit of 1-1150 µM and 0.098 µM (n = 3), respectively, with superior storage stability and considerable sensitivity. These results suggest that the proposed work can be successfully applied to the determination of CAP in milk and water samples.


Assuntos
Antibacterianos , Carbono , Cloranfenicol , Técnicas Eletroquímicas , Limite de Detecção , Leite , Cloranfenicol/análise , Cloranfenicol/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Carbono/química , Antibacterianos/análise , Leite/química , Animais , Poluentes Químicos da Água/análise , Eletrodos , Nitrogênio/química , Dióxido de Silício/química
10.
Entropy (Basel) ; 26(8)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39202159

RESUMO

With the integration of large-scale wind power into the power grid, the impact on system stability, especially the issue of low-frequency oscillations caused by small disturbances, is becoming increasingly prominent. Therefore, this paper proposes a damping quantitative analysis method for regional interconnected power systems incorporating large-scale wind power. Using the cross-entropy particle swarm optimization (CE-PSO) algorithm, the control parameters of wind turbines are optimized to suppress low-frequency oscillations in interconnected systems. The method begins with the state equation of the interconnected power system in two regions; it deduces the characteristic polynomial of the interconnected system, including wind farms, and takes into account the influence of wind power integration on the electrical connectivity of the system. Subsequently, the influence of wind turbine control parameters on the system is quantified, and a quantitative analysis model of the impact of wind power integration on system damping characteristics is constructed. Based on this, an optimization model for wind turbine control parameters is established, and the CE-PSO algorithm is utilized to achieve suppression of low-frequency oscillations in interconnected power grids with wind power integration. Finally, the accuracy and effectiveness of the proposed method are verified through a typical electromagnetic transient simulation model of the two-region interconnected power system.

11.
Pflege ; 2024 Mar 22.
Artigo em Alemão | MEDLINE | ID: mdl-38517238

RESUMO

The dual competence profile: A support of collaboration between practice and science. A qualitative descriptive study Abstract. Background: To ensure orientation towards needs existing in the realm of practice, the dual competence profile is mandatory at universities of applied sciences (UAS): in addition to academic qualifications, entrenchment in professional practice is demanded. However, it is unclear how needs, attitudes, and expectation of clinical practice regarding the interface between UAS and practice looks like. Thus, it is necessary to shed light on the cross-institutional and cross-divisional cooperation as well as on its participants. Aim: This article shows what needs and attitudes people from clinical practice have with regard to cooperation with the UAS and what they expect from persons with a dual competence profile. Methods: Guided individual and focus group interviews with 24 selected representatives from acute, rehabilitation and geriatric care institutions took place. The interviews address the following five block themes: "current state", "need for change", "areas for action", "needs" and "sustainability". Results: Practice institutions demonstrated a clear need for networking and knowledge circulation with the UAS, with a bilateral influence of four subcategories: overall goal, staff development, resources and general regulations. Conclusions: Persons with dual competency profiles provide a valid way for interconnecting higher education and practice institutions in a concrete manner. Their complex work environments require meaningful frameworks, shared goals, and the inclusion of key stakeholders.

12.
Small ; 19(44): e2208089, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37403299

RESUMO

The restricted porosity of most hydrogels established for in vitro 3D tissue engineering applications limits embedded cells with regard to their physiological spreading, proliferation, and migration behavior. To overcome these confines, porous hydrogels derived from aqueous two-phase systems (ATPS) are an interesting alternative. However, while developing hydrogels with trapped pores is widespread, the design of bicontinuous hydrogels is still challenging. Herein, an ATPS consisting of photo-crosslinkable gelatin methacryloyl (GelMA) and dextran is presented. The phase behavior, monophasic or biphasic, is tuned via the pH and dextran concentration. This, in turn, allows the formation of hydrogels with three distinct microstructures: homogenous nonporous, regular disconnected-pores, and bicontinuous with interconnected-pores. The pore size of the latter two hydrogels can be tuned from ≈4 to 100 µm. Cytocompatibility of the generated ATPS hydrogels is confirmed by testing the viability of stromal and tumor cells. Their distribution and growth pattern are cell-type specific but are also strongly defined by the microstructure of the hydrogel. Finally, it is demonstrated that the unique porous structure is sustained when processing the bicontinuous system by inkjet and microextrusion techniques. The proposed ATPS hydrogels hold great potential for 3D tissue engineering applications due to their unique tunable interconnected porosity.


Assuntos
Materiais Biocompatíveis , Dextranos , Materiais Biocompatíveis/química , Gelatina/química , Engenharia Tecidual/métodos , Hidrogéis/química , Metacrilatos , Alicerces Teciduais/química , Impressão Tridimensional
13.
Small ; 19(24): e2300234, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919815

RESUMO

Simultaneously achieving exceptional mechanical strength and resilience of graphene aerogel (GA) remains a challenge, while GA is an ideal candidate for formaldehyde removal. Herein, flexible polyethyleneimine (PEI) is grafted chemically onto carbon nanotube (CNT) surface, and CNT-PEI@reduced GA (rGA) is fabricated via hydrothermal self-assembly, pre-frozen, and hydrazine reduction process. Introducing CNT-PEI contributes to well-interconnected/robust 3D network construction by connecting reduced graphene oxide (rGO) nanosheets through enhancing cross-linking, while entangled CNT-PEI is intercalated into rGO layers to avoid serious restacking of sheets, producing larger surface area and more formaldehyde adsorption sites. Ultralight CNT-PEI@rGA exhibits extreme high strength (276.37 kPa), reversible compressibility at 90% strain, and structural stability, while FA adsorption capacity reached 568.41 mg g-1 , ≈3.28 times of rGA, derivable from synergistic chemical-physical adsorption effect. Furthermore, CNT-PEI@rGA is ground into powder for first preparing polyoxymethylene (POM)/CNT-PEI@rGA composite, while formaldehyde emission amount is 69.63%/73.96% lower than that of POM at 60/230 °C. Moreover, CNT-PEI@rGA presents outstanding piezoresistive-sensing and thermal insulation properties, exhibiting high strain sensitivity, wide strain detection range, and long-term durability.

14.
Small ; 19(10): e2206340, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36564352

RESUMO

Sodium-based dual-ion batteries (SDIBs) have become a new type of energy storage device with great application value because of their high operating voltage, high energy density, and low cost. However, transition-metal dichalcogenide (TMD) anodes show unsatisfactory Na+ electrochemical performance owing to the low intrinsic conductivity and inferior ion transport kinetics. Here, an elaborate design is developed to prepare a composite of WSSe nanosheets supported on a 3D cross-networked porous carbon skeleton (WSSe@CPCS), which possesses en-rich anion vacancies and WSSe with expanded inter-layer spacing, as well as an interconnected porous structure. As a result, the WSSe@CPCS anode for sodium-ion batteries (SIBs) exhibits preeminent reversible capacities, excellent cycle stability, and superior rate capability. The systematic electrochemical kinetic analysis and density functional theory results further show that the effect of anion vacancies and CPCS synergistically enhances the conductivity and reduces charge transfer resistance, thus making a great contribution to fast reaction kinetics. Finally, the implementations of the WSSe@CPCS anode in progressive SIB and DIB full-cell configurations exhibit satisfactory performance, which reveals their widely practical application. This research will provide an exciting approach to designing advanced defect-structured tungsten-based TMD materials for SIBs, DIBs, and even a broad range of energy storage.

15.
Small ; 19(26): e2207716, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36938701

RESUMO

Metal selenides are considered as one of the most promising anode materials for Na-ion batteries owing to high specific capacity and relatively higher electronic conductivity compared with metal sulfides or oxides. However, such anodes still suffer from huge volume change upon repeated Na+ insertion/extraction processes and simultaneously undergo severe shuttle effect of polyselenides, thus leading to poor electrochemical performance. Herein, a facile chemical-blowing and selenization strategy to fabricate 3D interconnected hybrids built from metal selenides (MSe, M = Mn, Co, Cr, Fe, In, Ni, Zn) nanoparticles encapsulated in in situ formed N-doped carbon foams (NCFs) is reported. Such hybrids not only provide ultrasmall active nanobuilding blocks (≈15 nm), but also efficiently anchor them inside the conductive NCFs, thus enabling both high-efficiency utilization of active components and high structural stability. On the other hand, Cu-driven replacement reaction is utilized for efficiently inhibiting the shuttle effect of polyselenides in ether-based electrolyte. Benefiting from the combined merits of the unique MSe@NCFs and the utilization of the conversion of metal selenides to copper selenides, the as-obtained hybrids (MnSe as an example) exhibit superior rate capability (386.6 mAh g-1 up to 8 A g-1 ) and excellent cycling stability (347.7 mAh g-1 at 4.0 A g-1 after 1200 cycles).

16.
Small ; 19(19): e2207536, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36772895

RESUMO

Introducing inorganic fillers into organic poly(ethylene oxide)(PEO)-based electrolyte has attracted substantial attention to enhance its ionic conductivity and mechanical strength, but limited inorganic-organic interphases are always caused by isolated particles agglomeration. Herein, a variety of sandwich structured metal oxide/reduced graphene oxide(rGO)/metal oxide nanocomposites to optimize lithium-ion conduction by interconnected amorphous organic-inorganic interphases in lithium metal batteries, are proposed. With the support of high surface area rGO, the agglomeration of metal oxide particles is precluded, forming continuous amorphous organic-inorganic interphases with stacked layer-by-layer structure, thus creating 3D interconnected lithium-ion transportation channels vertically and laterally. Besides, metal oxide nanoparticles with hydroxyls possess high affinity toward bis(tri-fluoromethanesulfonyl)imide anions by hydrogen bindings between hydroxyls and fluorine and metal-oxygen bonds, releasing more free lithium ions. Consequently, PEO-ZnO/rGO/ZnO electrolyte delivers superior ionic conductivity of 1.02 × 10-4 S cm-1 at 25 °C and lithium-ion transference number of 0.38 at 60 °C. Furthermore, ZnO/rGO/ZnO insertion promotes the formation of LiF-rich stable solid electrolyte interface, endowing Li symmetric cells with long-term cycling stability over 900 hours. The corresponding LiFePO4 cathode possesses a high reversible specific capacity of 130 mAh g-1 at 0.5C after cycling 300 cycles with a poor capacity fading of 0.05% per cycle.

17.
Small ; 19(30): e2208280, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36965037

RESUMO

High electrochemical polarization during a redox reaction in the electrode of aqueous zinc-bromine flow batteries largely limits its practical implementation as an effective energy storage system. This study demonstrates a rationally-designed composite electrode that exhibits a lower electrochemical polarization by providing a higher number of catalytically-active sites for faster bromine reaction, compared to a conventional graphite felt cathode. The composite electrode is composed of electrically-conductive graphite felt (GF) and highly active mesoporous tungsten oxynitride nanofibers (mWONNFs) that are prepared by electrospinning and simple heat treatments. Addition of the 1D mWONNFs to porous GF produces a web-like structure that significantly facilitates the reaction kinetics and ion diffusion. The cell performance achieves in this study demonstrated high energy efficiencies of 89% and 80% at current densities of 20 and 80 mA cm-2 , respectively. Furthermore, the cell can also be operated at a very high current density of 160 mA cm-2 , demonstrating an energy efficiency of 62%. These results demonstrate the effectiveness of the mWONNF/GF composite as the electrode material in zinc-bromine flow batteries.

18.
Sensors (Basel) ; 23(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37177440

RESUMO

This paper proposes a new observer approach used to simultaneously estimate both vehicle lateral and longitudinal nonlinear dynamics, as well as their unknown inputs. Based on cascade observers, this robust virtual sensor is able to more precisely estimate not only the vehicle state but also human driver external inputs and road attributes, including acceleration and brake pedal forces, steering torque, and road curvature. To overcome the observability and the interconnection issues related to the vehicle dynamics coupling characteristics, tire effort nonlinearities, and the tire-ground contact behavior during braking and acceleration, the linear-parameter-varying (LPV) interconnected unknown inputs observer (UIO) framework was used. This interconnection scheme of the proposed observer allows us to reduce the level of numerical complexity and conservatism. To deal with the nonlinearities related to the unmeasurable real-time variation in the vehicle longitudinal speed and tire slip velocities in front and rear wheels, the Takagi-Sugeno (T-S) fuzzy form was undertaken for the observer design. The input-to-state stability (ISS) of the estimation errors was exploited using Lyapunov stability arguments to allow for more relaxation and an additional robustness guarantee with respect to the disturbance term of unmeasurable nonlinearities. For the design of the LPV interconnected UIO, sufficient conditions of the ISS property were formulated as an optimization problem in terms of linear matrix inequalities (LMIs), which can be effectively solved with numerical solvers. Extensive experiments were carried out under various driving test scenarios, both in interactive simulations performed with the well-known Sherpa dynamic driving simulator, and then using the LAMIH Twingo vehicle prototype, in order to highlight the effectiveness and the validity of the proposed observer design.

19.
Int J Mol Sci ; 24(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37047743

RESUMO

Synergetic elongation of mesocotyl and coleoptile are crucial in governing maize seedlings emergence, especially for the maize sown in deep soil. Studying the genomic regions controlling maize deep-sowing tolerance would aid the development of new varieties that are resistant to harsh conditions, such as drought and low temperature during seed germination. Using 346 F2:3 maize population families from W64A × K12 cross at three sowing depths, we identified 33 quantitative trait loci (QTLs) for the emergence rate, mesocotyl, coleoptile, and seedling lengths via composite interval mapping (CIM). These loci explained 2.89% to 14.17% of phenotypic variation in a single environment, while 12 of 13 major QTLs were identified at two or more sowing environments. Among those, four major QTLs in Bin 1.09, Bin 4.08, Bin 6.01, and Bin 7.02 supported pleiotropy for multiple deep-sowing tolerant traits. Meta-analysis identified 17 meta-QTLs (MQTLs) based on 130 original QTLs from present and previous studies. RNA-Sequencing of mesocotyl and coleoptile in both parents (W64A and K12) at 3 cm and 20 cm sowing environments identified 50 candidate genes expressed differentially in all major QTLs and MQTLs regions: six involved in the circadian clock, 27 associated with phytohormones biosynthesis and signal transduction, seven controlled lignin biosynthesis, five regulated cell wall organization formation and stabilization, three were responsible for sucrose and starch metabolism, and two in the antioxidant enzyme system. These genes with highly interconnected networks may form a complex molecular mechanism of maize deep-sowing tolerance. Findings of this study will facilitate the construction of molecular modules for deep-sowing tolerance in maize. The major QTLs and MQTLs identified could be used in marker-assisted breeding to develop elite maize varieties.


Assuntos
Melhoramento Vegetal , Zea mays , Humanos , Zea mays/genética , Mapeamento Cromossômico , Locos de Características Quantitativas/genética , Fenótipo , Plântula/genética , RNA
20.
Entropy (Basel) ; 25(8)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37628188

RESUMO

This paper addresses the problem of decentralized safety control (DSC) of constrained interconnected nonlinear safety-critical systems under reinforcement learning strategies, where asymmetric input constraints and security constraints are considered. To begin with, improved performance functions associated with the actuator estimates for each auxiliary subsystem are constructed. Then, the decentralized control problem with security constraints and asymmetric input constraints is transformed into an equivalent decentralized control problem with asymmetric input constraints using the barrier function. This approach ensures that safety-critical systems operate and learn optimal DSC policies within their safe global domains. Then, the optimal control strategy is shown to ensure that the entire system is uniformly ultimately bounded (UUB). In addition, all signals in the closed-loop auxiliary subsystem, based on Lyapunov theory, are uniformly ultimately bounded, and the effectiveness of the designed method is verified by practical simulation.

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