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Bismuth halide perovskites are widely regarded as nontoxic alternatives to lead halide perovskites for optoelectronics and solar energy harvesting applications. With a tailorable composition and intriguing optical properties, bismuth halide perovskites are also promising candidates for tunable photonic devices. However, robust control of the anion composition in bismuth halide perovskites remains elusive. Here, we established chemical vapor deposition and anion exchange protocols to synthesize bismuth halide perovskite nanoflakes with controlled dimensions and variable compositions. In particular, we demonstrated the gradient bromide distribution by controlling the anion exchange and diffusion processes, which is spatially resolved by time-of-flight secondary ion mass spectrometry. Moreover, the optical waveguiding properties of bismuth halide perovskites can be modulated by flake thicknesses and anion compositions. With a unique gradient anion distribution and controllable optical properties, bismuth halide perovskites provide new possibilities for applications in optoelectronic devices and integrated photonics.
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Nitrogen-vacancy (NV-) centers in nanodiamonds have emerged as a versatile platform for a wide range of applications, including bioimaging, photonics, and quantum sensing. However, the widespread adoption of nanodiamonds in practical applications has been hindered by the challenges associated with patterning them into high-resolution features with sufficient throughput. In this work, we overcome these limitations by introducing a direct laser-writing bubble printing technique that enables the precise fabrication of two-dimensional nanodiamond patterns. The printed nanodiamonds exhibit a high packing density and strong photoluminescence emission, as well as robust optically detected magnetic resonance (ODMR) signals. We further harness the spatially resolved ODMR of the nanodiamond patterns to demonstrate the mapping of two-dimensional temperature gradients using high frame rate widefield lock-in fluorescence imaging. This capability paves the way for integrating nanodiamond-based quantum sensors into practical devices and systems, opening new possibilities for applications involving high-resolution thermal imaging and biosensing.
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Progress in optical manipulation has stimulated remarkable advances in a wide range of fields, including materials science, robotics, medical engineering, and nanotechnology. This Review focuses on an emerging class of optical manipulation techniques, termed heat-mediated optical manipulation. In comparison to conventional optical tweezers that rely on a tightly focused laser beam to trap objects, heat-mediated optical manipulation techniques exploit tailorable optothermo-matter interactions and rich mass transport dynamics to enable versatile control of matter of various compositions, shapes, and sizes. In addition to conventional tweezing, more distinct manipulation modes, including optothermal pulling, nudging, rotating, swimming, oscillating, and walking, have been demonstrated to enhance the functionalities using simple and low-power optics. We start with an introduction to basic physics involved in heat-mediated optical manipulation, highlighting major working mechanisms underpinning a variety of manipulation techniques. Next, we categorize the heat-mediated optical manipulation techniques based on different working mechanisms and discuss working modes, capabilities, and applications for each technique. We conclude this Review with our outlook on current challenges and future opportunities in this rapidly evolving field of heat-mediated optical manipulation.
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Temperatura Alta , Pinças Ópticas , Luz , Nanotecnologia/métodos , Óptica e FotônicaRESUMO
Carrier distribution and dynamics in semiconductor materials often govern their physical properties that are critical to functionalities and performance in industrial applications. The continued miniaturization of electronic and photonic devices calls for tools to probe carrier behavior in semiconductors simultaneously at the picosecond time and nanometer length scales. Here, we report pump-probe optical nanoscopy in the visible-near-infrared spectral region to characterize the carrier dynamics in silicon nanostructures. By coupling experiments with the point-dipole model, we resolve the size-dependent photoexcited carrier lifetime in individual silicon nanowires. We further demonstrate local carrier decay time mapping in silicon nanostructures with a sub-50 nm spatial resolution. Our study enables the nanoimaging of ultrafast carrier kinetics, which will find promising applications in the future design of a broad range of electronic, photonic, and optoelectronic devices.
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OBJECTIVES: To study the association of hypercoagulability with urinary protein and renal pathological damage in children with immunoglobulin A vasculitis with nephritis (IgAVN). METHODS: Based on the results of coagulation function, 349 children with IgAVN were divided into a hypercoagulability group consisting of 52 children and a non-hypercoagulability group consisting of 297 children. Urinary protein and renal pathological features were compared between the two groups, and the factors influencing the formation of hypercoagulability in children with IgAVN were analyzed. RESULTS: Compared with the non-hypercoagulability group, the hypercoagulability group had significantly higher levels of urinary erythrocyte count, 24-hour urinary protein, urinary protein/creatinine, urinary immunoglobulin G/creatinine, and urinary N-acetyl-ß-D-glucosaminidase (P<0.05). The hypercoagulability group also had a significantly higher proportion of children with a renal pathological grade of III-IV, diffuse mesangial proliferation, capillary endothelial cell proliferation, or >25% crescent formation (P<0.05). The multivariate logistic regression analysis showed that capillary endothelial cell proliferation and glomerular crescent formation >25% were associated with the formation of hypercoagulability in children with IgAVN (P<0.05). CONCLUSIONS: The renal injury in IgAVN children with hypercoagulability is more severe, with greater than 25% crescent formation and increased proliferation of glomerular endothelial cells being important contributing factors that exacerbate the hypercoagulable state in IgAVN.
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Vasculite por IgA , Nefrite , Trombofilia , Criança , Humanos , Creatinina , Células Endoteliais , Rim , Vasculite por IgA/complicações , Trombofilia/etiologia , Imunoglobulina ARESUMO
BACKGROUND: Epilepsy is the second most prevalent neurological disease. Although there are many antiseizure drugs, approximately 30% of cases are refractory to treatment. Temporal lobe epilepsy (TLE) is the most common epilepsy subtype, and previous studies have reported that hippocampal inflammation is an important mechanism associated with the occurrence and development of TLE. However, the inflammatory biomarkers associated with TLE are not well defined. METHODS: In our study, we merged human hippocampus datasets (GSE48350 and GSE63808) through batch correction and generally verified the diagnostic roles of inflammation-related genes (IRGs) and subtype classification according to IRGs in epilepsy through differential expression, random forest, support vector machine, nomogram, subtype classification, enrichment, proteinâprotein interaction, immune cell infiltration, and immune function analyses. Finally, we detected the location and expression of inhibitor of metalloproteinase-1 (TIMP1) in epileptic patients and kainic acid-induced epileptic mice. RESULTS: According to the bioinformatics analysis, we identified TIMP1 as the most significant IRG associated with TLE, and we found that TIMP1 was mainly located in cortical neurons and scantly expressed in cortical gliocytes by immunofluorescence staining. We detected decreased expression of TIMP1 by quantitative real-time polymerase chain reaction and western blotting. CONCLUSION: TIMP1, the most significant IRG associated with TLE, might be a novel and promising biomarker to study the mechanism of epilepsy and guide the discovery of new drugs for its treatment.
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Epilepsia do Lobo Temporal , Epilepsia , Humanos , Camundongos , Animais , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia/metabolismo , Hipocampo/metabolismo , Inflamação/metabolismo , Biomarcadores/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismoRESUMO
Paternal care plays a critical role in the development of brain and behaviors in offspring in monogamous species. However, the neurobiological mechanisms, especially the neuronal circuity, underlying paternal care is largely unknown. Using socially monogamous male mandarin voles (Microtus mandarinus) with high levels of paternal care, we found that paraventricular nucleus of the hypothalamus (PVN) to ventral tegmental area (VTA) or nucleus accumbens (NAc) oxytocin (OT) neurons are activated during paternal care. Chemogenetic activation/inhibition of the PVN OT projection to VTA promoted/decreased paternal care, respectively. Chemogenetic inhibition of the PVN to VTA OT pathway reduced dopamine (DA) release in the NAc of male mandarin voles during licking and grooming of pups as revealed by in vivo fiber photometry. Optogenetic activation/inhibition of the VTA to NAc DA pathway possibly enhanced/suppressed paternal behaviors, respectively. Furthermore, chemogenetic activation/inhibition of PVN to NAc OT circuit enhanced/inhibited paternal care. This finding is a first step toward delineating the neuronal circuity underlying paternal care and may have implications for treating abnormalities in paternal care associated with paternal postpartum depression or paternal abuse.SIGNIFICANCE STATEMENT Paternal behavior is essential for offspring survival and development in some mammalian species. However, the circuit mechanisms underlying the paternal brain are poorly understood. We show that manipulation of paraventricular nucleus of the hypothalamus (PVN) to ventral tegmental area (VTA) oxytocin (OT) projections as well as VTA to nucleus accumbens (NAc) DA projections promote paternal behaviors. Inhibition the PVN to VTA OT pathway reduces DA release in the NAc during pup licking and grooming. PVN to NAc OT circuit is also essential for paternal behaviors. Our findings identify two new neural circuits that modulate paternal behaviors.
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Comportamento Animal/fisiologia , Vias Neurais/metabolismo , Ocitocina/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Comportamento Paterno/fisiologia , Animais , Arvicolinae , MasculinoRESUMO
Subwavelength nanostructures with tunable compositions and geometries show favorable optical functionalities for the implementation of nanophotonic systems. Precise and versatile control of structural configurations on solid substrates is essential for their applications in on-chip devices. Here, we report all-solid-phase reconfigurable chiral nanostructures with silicon nanoparticles and nanowires as the building blocks in which the configuration and chiroptical response can be tailored on-demand by dynamic manipulation of the silicon nanoparticle. We reveal that the optical chirality originates from the handedness-dependent coupling between optical resonances of the silicon nanoparticle and the silicon nanowire via numerical simulations and coupled-mode theory analysis. Furthermore, the coexisting electric and magnetic resonances support strong enhancement of optical near-field chirality, which enables label-free enantiodiscrimination of biomolecules in single nanostructures. Our results not only provide insight into the design of functional high-index materials but also bring new strategies to develop adaptive devices for photonic and electronic applications.
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Nanopartículas , Nanoestruturas , Óptica e Fotônica , Fótons , SilícioRESUMO
Subterranean rodents could maintain their normal activities in hypoxic environments underground. Eospalax fontanierii, as one kind of subterranean rodent found in China can survive very low oxygen concentration in labs. It has been demonstrated that long non-coding RNAs (lncRNAs) have important roles in gene expression regulations at different levels and some lncRNAs were found as hypoxia-regulated lncRNAs in cancers. We predicted thousands of lncRNAs in the liver and heart tissues by analyzing RNA-Seq data in Eospalax fontanierii. Those lncRNAs often have shorter lengths, lower expression levels, and lower GC contents than mRNAs. Majors of lncRNAs have expression peaks in hypoxia conditions. We found 1128 DE-lncRNAs (differential expressed lncRNAs) responding to hypoxia. To search the miRNA regulation network for lncRNAs, we predicted 471 and 92 DE-lncRNAs acting as potential miRNA target and target mimics, respectively. We also predicted the functions of DE-lncRNAs based on the co-expression networks of lncRNA-mRNA. The DE-lncRNAs participated in the functions of biological regulation, signaling, development, oxoacid metabolic process, lipid metabolic/biosynthetic process, and catalytic activity. As the first study of lncRNAs in Eospalax fontanierii, our results show that lncRNAs are popular in transcriptome widely and can participate in multiple biological processes in hypoxia responses.
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Regulação da Expressão Gênica , Hipóxia/genética , RNA Longo não Codificante/genética , Roedores/genética , Animais , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Hipóxia/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , Roedores/metabolismo , TranscriptomaRESUMO
Nanoaperture-based plasmonic tweezers have shown tremendous potential in trapping, sensing, and spectroscopic analysis of nano-objects with single-molecule sensitivity. However, the trapping process is often diffusion-limited and therefore suffers from low-throughput. Here, we present bubble- and convection-assisted trapping techniques, which use opto-thermally generated Marangoni and Rayleigh-Bénard convection flow to rapidly deliver particles from large distances to the nanoaperture instead of relying on normal diffusion, enabling a reduction of 1-2 orders of magnitude in particle-trapping time (i.e., time before a particle is trapped). At a concentration of 2 × 107 particles/mL, average particle-trapping times in bubble- and convection-assisted trapping were 7 and 18 s, respectively, compared with more than 300 s in the diffusion-limited trapping. Trapping of a single particle at an ultralow concentration of 2 × 106 particles/mL was achieved within 2-3 min, which would otherwise take several hours in the diffusion-limited trapping. With their quick delivery and local concentrating of analytes at the functional surfaces, our convection- and bubble-assisted trapping could lead to enhanced sensitivity and throughput of nanoaperture-based plasmonic sensors.
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Nanoestruturas , Pinças Ópticas , NanotecnologiaRESUMO
Melatonin is a crucial neurohormone synthesized in the pineal gland that influences the physiology of animals. The molecular mechanism of norepinephrine control of the synthesis of melatonin is well documented; however, few reports have described the effects of epinephrine on the synthesis of melatonin. In this study, the effect of epinephrine on melatonin synthesis was investigated by adding different concentrations of epinephrine or norepinephrine to broiler pineal glands cultured in vitro. In addition, we investigated how epinephrine regulates the synthesis of melatonin and the transcription of the key melatonin synthesis enzyme AANAT. We determined the abundance of melatonin, norepinephrine, and epinephrine in broiler serum and the mRNA expression levels of key enzymes under different light conditions. The minimum concentrations of epinephrine and norepinephrine required to recover the melatonin synthesis rhythm in pineal cells were 10-13 and 10-11 mol/L, respectively. Under various light durations, epinephrine reached maximum levels two hours earlier than melatonin. These results demonstrate for the first time that epinephrine can increase the synthesis of melatonin by increasing the transcription of AANAT.
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Arilalquilamina N-Acetiltransferase/biossíntese , Proteínas Aviárias/biossíntese , Galinhas/metabolismo , Epinefrina/farmacologia , Melatonina/biossíntese , Glândula Pineal/metabolismo , Transcrição Gênica/efeitos dos fármacos , Animais , Arilalquilamina N-Acetiltransferase/genética , Proteínas Aviárias/genética , Galinhas/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Melatonina/genéticaRESUMO
BACKGROUND: Chorioamnionitis and fetal inflammation are principal causes of neuropathology detected after birth, particularly in very preterm infants. Preclinical studies show that umbilical cord blood (UCB) cells are neuroprotective, but it is uncertain if allogeneic UCB cells are a feasible early intervention for preterm infants. In contrast, mesenchymal stem cells (MSCs) are more readily accessible and show strong anti-inflammatory benefits. We aimed to compare the neuroprotective benefits of UCB versus MSCs in a large animal model of inflammation-induced preterm brain injury. We hypothesized that MSCs would afford greater neuroprotection. METHODS: Chronically instrumented fetal sheep at 0.65 gestation received intravenous lipopolysaccharide (150 ng; 055:B5, n = 8) over 3 consecutive days; or saline for controls (n = 8). Cell-treated animals received 108 UCB mononuclear cells (n = 7) or 107 umbilical cord MSCs (n = 8), intravenously, 6 h after the final lipopolysaccharide dose. Seven days later, cerebrospinal fluid and brain tissue was collected for analysis. RESULTS: Lipopolysaccharide induced neuroinflammation and apoptosis, and reduced the number of mature oligodendrocytes. MSCs reduced astrogliosis, but UCB did not have the same effect. UCB significantly decreased cerebral apoptosis and protected mature myelinating oligodendrocytes, but MSCs did not. CONCLUSION: UCB appears to better protect white matter development in the preterm brain in response to inflammation-induced brain injury in fetal sheep.
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Astrócitos/patologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/terapia , Sangue Fetal/citologia , Gliose/fisiopatologia , Inflamação/metabolismo , Células-Tronco Mesenquimais/citologia , Animais , Animais Recém-Nascidos , Apoptose , Morte Celular , Modelos Animais de Doenças , Feminino , Humanos , Leucócitos Mononucleares/citologia , Lipopolissacarídeos , Masculino , Neuroproteção , Oligodendroglia/citologia , Ovinos , Substância Branca/patologiaRESUMO
With the increase in blood viscosity, the blood circulation resistance will increase when animals are in hypoxia. However, these phenomenons do not appear in hypoxic-adapted animals. Eospalax fontanierii is a subterranean rodent and is an ideal species for research in hypoxia adaptation. Eighteen healthy adult E. fontanierii individuals were equally divided into three groups that were exposed to 21% O2 for 1 week, 10.5% O2 for 44 h, and 6.5% O2 for 6 h, and then, the hearts were collected for transcriptome sequencing. After differentially expressed analysis, fibrinogen genes were selected for qPCR and Western blot verification. Eighteen healthy adult Sprague-Dawley rats (SD rats) were treated with the same oxygen concentrations, and their hearts were simultaneously subjected to qPCR. The quantitative real-time PCR and Western blot results were completely opposite to those of the rats. E. fontanierii fibrinogen mRNA was significantly downregulated when expressed under the conditions of 10.5% and 6.5% O2 compared with 21% O2. Correspondingly, fibrinogen mRNA in E. fontanierii was expressed at lower levels than SD rats in 10.5% and 6.5% O2. After tail-cutting experiment, the results showed that the coagulation rate of E. fontanierii was slowed down under hypoxic conditions. These results showed that E. fontanierii may downregulate the expression of fibrinogen mRNA in hypoxia to reduce the aggregation of red blood cells and platelets in plasma, which may prevent blood from becoming overly viscous, and at the same time, reduce blood circulation resistance and the probability of thrombosis in hypoxia to protect the heart.
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Fibrinogênio , Hipóxia/genética , Miocárdio/metabolismo , Roedores , Transcriptoma/genética , Animais , Bases de Dados Genéticas , Regulação para Baixo/genética , Ecossistema , Fibrinogênio/genética , Fibrinogênio/metabolismo , Hipóxia/metabolismo , Miocárdio/química , Oxigênio/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Roedores/genética , Roedores/fisiologia , Análise de Sequência de RNA , Transcriptoma/fisiologiaRESUMO
BACKGROUND: Infants born preterm following exposure to in utero inflammation/chorioamnionitis are at high risk of brain injury and life-long neurological deficits. In this study, we assessed the efficacy of early intervention umbilical cord blood (UCB) cell therapy in a large animal model of preterm brain inflammation and injury. We hypothesised that UCB treatment would be neuroprotective for the preterm brain following subclinical fetal inflammation. METHODS: Chronically instrumented fetal sheep at 0.65 gestation were administered lipopolysaccharide (LPS, 150 ng, 055:B5) intravenously over 3 consecutive days, followed by 100 million human UCB mononuclear cells 6 h after the final LPS dose. Controls were administered saline instead of LPS and cells. Ten days after the first LPS dose, the fetal brain and cerebrospinal fluid were collected for analysis of subcortical and periventricular white matter injury and inflammation. RESULTS: LPS administration increased microglial aggregate size, neutrophil recruitment, astrogliosis and cell death compared with controls. LPS also reduced total oligodendrocyte count and decreased mature myelinating oligodendrocytes. UCB cell therapy attenuated cell death and inflammation, and recovered total and mature oligodendrocytes, compared with LPS. CONCLUSIONS: UCB cell treatment following inflammation reduces preterm white matter brain injury, likely mediated via anti-inflammatory actions.
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Lesões Encefálicas/terapia , Encefalite/terapia , Sangue Fetal/citologia , Lipopolissacarídeos/farmacologia , Animais , Corioamnionite/terapia , Modelos Animais de Doenças , Feminino , Feto/citologia , Humanos , Microglia/citologia , Gravidez , Ovinos , Substância Branca/efeitos dos fármacosRESUMO
Lipid vesicles are important biological assemblies, which are critical to biological transport processes, and vesicles prepared in the lab are a workhorse for studies of drug delivery, protein unfolding, biomolecular interactions, compartmentalized chemistry, and stimuli-responsive sensing. The current method of using optical tweezers for holding lipid vesicles in place for single-vesicle studies suffers from limitations such as high optical power, rigorous optics, and small difference in the refractive indices of vesicles and water. Herein, we report the use of plasmonic heating to trap vesicles in a temperature gradient, allowing long-range attraction, parallel trapping, and dynamic manipulation. The capabilities and limitations with respect to thermal effects on vesicle structure and optical spectroscopy are discussed. This simple approach allows vesicle manipulation using down to 3 orders of magnitude lower optical power and at least an order of magnitude higher trapping stiffness per unit power than traditional optical tweezers while using a simple optical setup. In addition to the benefit provided by the relaxation of these technical constraints, this technique can complement optical tweezers to allow detailed studies on thermophoresis of optically trapped vesicles and effects of locally generated thermal gradients on the physical properties of lipid vesicles. Finally, the technique itself and the large-scale collection of vesicles have huge potential for future studies of vesicles relevant to detection of exosomes, lipid-raft formation, and other areas relevant to the life sciences.
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Pinças Ópticas , Lipossomas Unilamelares/química , Calefação , Tamanho da Partícula , Transição de Fase , Fosfatidilgliceróis/química , TemperaturaRESUMO
BACKGROUNDWhite matter brain injury in preterm infants can induce neurodevelopmental deficits. Umbilical cord blood (UCB) cells demonstrate neuroprotective properties, but it is unknown whether cells obtained from preterm cord blood (PCB) vs. term cord blood (TCB) have similar efficacy. This study compared the ability of TCB vs. PCB cells to reduce white matter injury in preterm fetal sheep.METHODSHypoxia-ischemia (HI) was induced in fetal sheep (0.7 gestation) by 25 min umbilical cord occlusion. Allogeneic UCB cells from term or preterm sheep, or saline, were administered to the fetus at 12 h after HI. The fetal brain was collected at 10-day post HI for assessment of white matter neuropathology.RESULTSHI (n=7) induced cell death and microglial activation and reduced total oligodendrocytes and CNPase+myelin protein in the periventricular white matter and internal capsule when compared with control (n=10). Administration of TCB or PCB cells normalized white matter density and reduced cell death and microgliosis (P<0.05). PCB prevented upregulation of plasma tumor necrosis factor (TNF)-a, whereas TCB increased anti-inflammatory interleukin (IL)-10 (P<0.05). TCB, but not PCB, reduced circulating oxidative stress.CONCLUSIONSTCB and PCB cells reduced preterm HI-induced white matter injury, primarily via anti-inflammatory actions. The secondary mechanisms of neuroprotection appear different following TCB vs. PCB administration.
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Lesões Encefálicas/prevenção & controle , Sangue Fetal/citologia , Hipóxia-Isquemia Encefálica/prevenção & controle , Nascimento Prematuro , Carneiro Doméstico/embriologia , Animais , Lesões Encefálicas/patologia , Morte Celular , Proliferação de Células , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Hipóxia-Isquemia Encefálica/patologia , Microglia/patologia , Estresse Oxidativo , Substância Branca/lesõesRESUMO
The collective motion observed in living active matter, such as fish schools and bird flocks, is characterized by its dynamic and complex nature, involving various moving states and transitions. By tailoring physical interactions or incorporating information exchange capabilities, inanimate active particles can exhibit similar behavior. However, the lack of synchronous and arbitrary control over individual particles hinders their use as a test system for the study of more intricate collective motions in living species. Herein, a novel optical feedback control system that enables the mimicry of collective motion observed in living objects using active particles is proposed. This system allows for the experimental investigation of the velocity alignment, a seminal model of collective motion (known as the Vicsek model), in a microscale perturbed environment with controllable and realistic conditions. The spontaneous formation of different moving states and dynamic transitions between these states is observed. Additionally, the high robustness of the active-particle group at the critical density under the influence of different perturbations is quantitatively validated. These findings support the effectiveness of velocity alignment in real perturbed environments, thereby providing a versatile platform for fundamental studies on collective motion and the development of innovative swarm microrobotics.
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To explore the compensation effect of aeration on tomato vegetative and reproductive growth in arid and semi-arid areas, a two-year field experiment was conducted with four micro-nano aeration ratios (0%, 5%, 10%, and 15%) and three nitrogen topdressing levels (80, 60, and 40 kg·ha-1) during the tomato growth period in Ningxia, China. The results showed that increasing the aeration ratio in the range of 0-15% was conducive to the enhancement of tomato root vigor (the ability of triphenyltetrazolium chloride to be reduced, 3-104%) and the leaf net photosynthetic rate (14-63%), favorable to the facilitation of plant dry matter accumulation (3-59%) and plant nitrogen accumulation (2-70%), and beneficial to the improvement of tomato yield (12-44%) and fruit quality. Interestingly, since the aeration ratio exceeded 10%, the increase in the aeration ratio showed no significant effects on the single-fruit weight, tomato yield, and fruit quality. Moreover, with aerated underground drip irrigation, properly reducing the traditional nitrogen topdressing level (80 kg·ha-1) by 25% was favorable for enhancing tomato root vigor (5-31%), increasing tomato yield (0.5-9%), and improving fruit soluble solid accumulation (2-5%) and soluble sugar formation (4-9%). Importantly, increasing the aeration ratio by 5% could compensate for the adverse effects of reducing the nitrogen topdressing level by 25% by improving the leaf photosynthetic rate, promoting plant dry matter accumulation, increasing tomato yield, and enhancing the soluble solid and soluble sugar accumulation in tomato fruits. Synthetically considering the decrease in the nitrogen topdressing amount, leading to plant growth promotion, a tomato yield increase, and fruit quality improvement, a favorable nitrogen topdressing level of 60 kg·ha-1 and the corresponding proper aeration ratio of 10% were suggested for tomato underground drip irrigation in the Yinbei Irrigation District of Ningxia.
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The electronic and optical properties of 2D transition metal dichalcogenides are dominated by strong excitonic resonances. Exciton dynamics plays a critical role in the functionality and performance of many miniaturized 2D optoelectronic devices; however, the measurement of nanoscale excitonic behaviors remains challenging. Here, a near-field transient nanoscopy is reported to probe exciton dynamics beyond the diffraction limit. Exciton recombination and exciton-exciton annihilation processes in monolayer and bilayer MoS2 are studied as the proof-of-concept demonstration. Moreover, with the capability to access local sites, intriguing exciton dynamics near the monolayer-bilayer interface and at the MoS2 nano-wrinkles are resolved. Such nanoscale resolution highlights the potential of this transient nanoscopy for fundamental investigation of exciton physics and further optimization of functional devices.