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1.
Nature ; 589(7841): 214-219, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33408416

RESUMO

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

2.
Nature ; 582(7813): 501-505, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32541968

RESUMO

Quantum key distribution (QKD)1-3 is a theoretically secure way of sharing secret keys between remote users. It has been demonstrated in a laboratory over a coiled optical fibre up to 404 kilometres long4-7. In the field, point-to-point QKD has been achieved from a satellite to a ground station up to 1,200 kilometres away8-10. However, real-world QKD-based cryptography targets physically separated users on the Earth, for which the maximum distance has been about 100 kilometres11,12. The use of trusted relays can extend these distances from across a typical metropolitan area13-16 to intercity17 and even intercontinental distances18. However, relays pose security risks, which can be avoided by using entanglement-based QKD, which has inherent source-independent security19,20. Long-distance entanglement distribution can be realized using quantum repeaters21, but the related technology is still immature for practical implementations22. The obvious alternative for extending the range of quantum communication without compromising its security is satellite-based QKD, but so far satellite-based entanglement distribution has not been efficient23 enough to support QKD. Here we demonstrate entanglement-based QKD between two ground stations separated by 1,120 kilometres at a finite secret-key rate of 0.12 bits per second, without the need for trusted relays. Entangled photon pairs were distributed via two bidirectional downlinks from the Micius satellite to two ground observatories in Delingha and Nanshan in China. The development of a high-efficiency telescope and follow-up optics crucially improved the link efficiency. The generated keys are secure for realistic devices, because our ground receivers were carefully designed to guarantee fair sampling and immunity to all known side channels24,25. Our method not only increases the secure distance on the ground tenfold but also increases the practical security of QKD to an unprecedented level.

3.
Proc Natl Acad Sci U S A ; 120(13): e2215189120, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36943886

RESUMO

The Mars-van Krevelen mechanism is the foundation for oxide-catalyzed oxidation reactions and relies on spatiotemporally separated redox steps. Herein, we demonstrate the tunability of this separation with peroxide species formed by excessively adsorbed oxygen, thereby modifying the catalytic activity and selectivity of the oxide. Using CuO as an example, we show that a surface layer of peroxide species acts as a promotor to significantly enhance CuO reducibility in favor of H2 oxidation but conversely as an inhibitor to suppress CuO reduction against CO oxidation. Together with atomistic modeling, we identify that this opposite effect of the peroxide on the two oxidation reactions stems from its modification on coordinately unsaturated sites of the oxide surface. By differentiating the chemical functionality between lattice oxygen and peroxide, these results are closely relevant to a wide range of catalytic oxidation reactions using excessively adsorbed oxygen to activate lattice oxygen and tune the activity and selectivity of redox sites.

4.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35145023

RESUMO

Insulin resistance and ß-cell dysfunction are two main molecular bases yet to be further elucidated for type 2 diabetes (T2D). Accumulating evidence indicates that stimulator of interferon genes (STING) plays an important role in regulating insulin sensitivity. However, its function in ß-cells remains unknown. Herein, using global STING knockout (STING-/-) and ß-cell-specific STING knockout (STING-ßKO) mouse models, we revealed a distinct role of STING in the regulation of glucose homeostasis through peripheral tissues and ß-cells. Specially, although STING-/- beneficially alleviated insulin resistance and glucose intolerance induced by high-fat diet, it surprisingly impaired islet glucose-stimulated insulin secretion (GSIS). Importantly, STING is decreased in islets of db/db mice and patients with T2D, suggesting a possible role of STING in ß-cell dysfunction. Indeed, STING-ßKO caused glucose intolerance due to impaired GSIS, indicating that STING is required for normal ß-cell function. Islet transcriptome analysis showed that STING deficiency decreased expression of ß-cell function-related genes, including Glut2, Kcnj11, and Abcc8, contributing to impaired GSIS. Mechanistically, the assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and cleavage under targets and tagmentation (CUT&Tag) analyses suggested that Pax6 was the transcription factor that might be associated with defective GSIS in STING-ßKO mice. Indeed, Pax6 messenger RNA and protein levels were down-regulated and its nuclear localization was lost in STING-ßKO ß-cells. Together, these data revealed a function of STING in the regulation of insulin secretion and established pathophysiological significance of fine-tuned STING within ß-cells and insulin target tissues for maintaining glucose homeostasis.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Intolerância à Glucose/induzido quimicamente , Glucose/metabolismo , Insulina/metabolismo , Proteínas de Membrana/metabolismo , Animais , Diabetes Mellitus Experimental , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Regulação da Expressão Gênica , Homeostase , Humanos , Insulina/sangue , Resistência à Insulina , Células Secretoras de Insulina , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout
5.
Opt Express ; 32(7): 11849-11862, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571023

RESUMO

A novel mid-infrared methane remote sensor integrated on a movable platform based on a 3.291-µm interband cascade laser (ICL) and wavelength modulation spectroscopy (WMS) is proposed. A transmitting-receiving coaxial, visualized optical layout is employed to minimize laser energy loss. Using a hollow retro-reflector remotely deployed as a cooperative target, the atmospheric average methane concentration over a 100-meter optical range is measured with high sensitivity. A deep neural network (DNN) filter is used for second harmonic (2f) signal denoising to compensate for the performance shortcomings of conventional filtering. Allan deviation analysis indicated that after applying the DNN filter, the limit of detection (LOD) of methane was 86.62 ppb with an average time of 1 s, decreasing to 12.03 ppb with an average time of 229 s, which is a significant promotion compared to similar work reported. The high sensitivity and stability of the proposed sensor are shown through a 24-hour continuous monitoring experiment of atmospheric methane conducted outdoors, providing a new solution for high-sensitivity remote sensing of atmospheric methane.

6.
Opt Express ; 32(7): 10962-10978, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570957

RESUMO

We propose a novel methane leakage rate remote sensor that combines a single-photon avalanche diode detector with a near-infrared 1653.7 nm low-power laser. The proposed M sequence and triangle wave signal modulation method simultaneously realizes the detection of methane leakage and target point clouds. Innovatively, the sensor's methane concentration and leakage rate quantification ability were simulated by combining the Gaussian plume diffusion model and the Risley prism. The effects of the prism rotation ratio, wind speed, leakage rate, atmospheric stability (AS), target reflectivity, signal averaging period, and concentration spatial interpolation method on leakage rate are discussed. When plume methane concentrations reduce from 10,000 to 500 ppm·m, the relative concentration bias rise from 1% to 30%, the absolute concentration bias is approximately 100 ppm·m. Two spatial concentration interpolation methods introduced leakage rate bias ranging from 6%-25%. For a low AS, the leakage rate bias under the cubic interpolation method was small (approximately 1.6%). In addition, when the initial leakage rate increased from 100 to 1,000 mg/s, the leakage rate bias was approximately 20% smaller.

7.
J Pineal Res ; 76(4): e12959, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38738543

RESUMO

10-Hydroxycamptothecin (HCPT) is a widely used clinical anticancer drug but has a significant side effect profile. Melatonin has a beneficial impact on the chemotherapy of different cancer cells and reproductive processes, but the effect and underlying molecular mechanism of melatonin's involvement in the HCPT-induced side effects in cells, especially in the testicular cells, are poorly understood. In this study, we found that melatonin therapy significantly restored HCPT-induced testicular cell damage and did not affect the antitumor effect of HCPT. Further analysis found that melatonin therapy suppressed HCPT-induced DNA damage associated with ataxia-telangiectasia mutated- and Rad3-related and CHK1 phosphorylation levels in the testis. Changes in apoptosis-associated protein levels (Bax, Bcl-2, p53, and Cleaved caspase-3) and in reactive oxygen species-associated proteins (Nrf2 and Keap1) and index (malondialdehyde and glutathione) suggested that melatonin treatment relieved HCPT-induced cell apoptosis and oxidative damage, respectively. Mechanistically, melatonin-activated autophagy proteins (ATG7, Beclin1, and LC3bII/I) may induce p62-dependent autophagy to degrade Keap1, eliciting Nrf2 from Keap1-Nrf2 interaction to promote antioxidant enzyme expression such as HO-1, which would salvage HCPT-induced ROS production and mitochondrial dysfunction. Collectively, this study reveals that melatonin therapy may protect testicular cells from HCPT-induced damage via the activation of autophagy, which alleviates oxidative stress, mitochondrial dysfunction, and cell apoptosis.


Assuntos
Apoptose , Camptotecina , Melatonina , Estresse Oxidativo , Transdução de Sinais , Testículo , Animais , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Camptotecina/farmacologia , Camptotecina/análogos & derivados , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Melatonina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo
8.
Clin Rehabil ; 38(6): 793-801, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38295341

RESUMO

OBJECTIVE: To investigate the effect of quick acupuncture combined with rehabilitation therapy on motor and swallowing function of patients with stroke. DESIGN: A retrospective study. SETTING: Single center study. PARTICIPANTS: One hundred and twenty patients with stroke were divided into control and observation group based on the therapeutic regimen. INTERVENTION: Control group (n = 60) only received rehabilitation therapy, and observation group (n = 60) received rehabilitation therapy combined with quick acupuncture. Acupuncture was performed once a day, and 6 times/week for 4 consecutive weeks. MAIN MEASURES: The simplified Fugl-Meyer assessment scale and Barthel index were used to assess limb motor function and daily living ability. The Dysphagia Outcome Severity Scale and Swallowing Quality of Life questionnaire were conducted to estimate the dysphagia severity and life quality of patients with swallowing disorders. The therapeutic efficacy and complications after treatment were analyzed and counted. RESULTS: After treatment, the scores of the observation group were significantly improved compared with the control group (P < 0.05). In the observation group, the therapeutic efficacy was 93% (n = 56); the complication rate was 5% (n = 3); the therapeutic efficacy of the control group was 75% (n = 45); and the complication rate was 25% (n = 15), indicating that the therapeutic efficacy of the observation group is better and the incidence of complications is lower than that of the control group. CONCLUSION: This study suggests that rehabilitation therapy combined with rapid acupuncture therapy has a potential therapeutic effect on the relief of swallowing and motor dysfunction after stroke.


Assuntos
Terapia por Acupuntura , Transtornos de Deglutição , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Reabilitação do Acidente Vascular Cerebral/métodos , Terapia por Acupuntura/métodos , Pessoa de Meia-Idade , Transtornos de Deglutição/reabilitação , Transtornos de Deglutição/etiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Idoso , Resultado do Tratamento , Terapia Combinada , Qualidade de Vida , Recuperação de Função Fisiológica , Índice de Gravidade de Doença
9.
J Dairy Sci ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004139

RESUMO

The transgalactosylase activity of ß-galactosidases offers a convenient and promising strategy for conversion of lactose into high-value oligosaccharides, such as galacto-oligosaccharides (GOS) and human milk oligosaccharides (HMOs). In this study, we cloned and biochemically characterized a novel C-terminally truncated ß-galactosidase (PaBgal2A-D) from Paenibacillus antarcticus with high transglycosylation activity. PaBgal2A-D is a member of glycoside hydrolase (GH) family 2. The optimal pH and temperature of PaBgal2A-D were determined to be pH 6.5 and 50°C, respectively. It was relatively stable within pH 5.0-8.0 and up to 50°C. PaBgal2A-D showed high transglycosylation activity for GOS synthesis, and the maximum yield of 50.8% (wt/wt) was obtained in 2 h. Moreover, PaBgal2A-D could synthesize lacto-N-neotetraose (LNnT) using lactose and lacto-N-triose II (LNT2), with a conversion rate of 16.4%. This study demonstrated that PaBgal2A-D could be a promising tool to prepare GOS and LNnT.

10.
Ecotoxicol Environ Saf ; 276: 116318, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626609

RESUMO

Perfluorooctane sulfonate (PFOS), an officially listed persistent organic pollutant, is a widely distributed perfluoroalkyl substance. Epidemiological studies have shown that PFOS is intimately linked to the occurrence of insulin resistance (IR). However, the detailed mechanism remains obscure. In previous studies, we found that mitochondrial calcium overload was concerned with hepatic IR induced by PFOS. In this study, we found that PFOS exposure noticeably raised lysosomal calcium in L-02 hepatocytes from 0.5 h. In the PFOS-cultured L-02 cells, inhibiting autophagy alleviated lysosomal calcium overload. Inhibition of mitochondrial calcium uptake aggravated the accumulation of lysosomal calcium, while inhibition of lysosomal calcium outflowing reversed PFOS-induced mitochondrial calcium overload and IR. Transient receptor potential mucolipin 1 (TRPML1), the calcium output channel of lysosomes, interacted with voltage-dependent anion channel 1 (VDAC1), the calcium intake channel of mitochondria, in the PFOS-cultured cells. Moreover, we found that ATP synthase F1 subunit beta (ATP5B) interacted with TRPML1 and VDAC1 in the L-02 cells and the liver of mice under PFOS exposure. Inhibiting ATP5B expression or restraining the ATP5B on the plasma membrane reduced the interplay between TRPML1 and VDAC1, reversed the mitochondrial calcium overload and deteriorated the lysosomal calcium accumulation in the PFOS-cultured cells. Our research unveils the molecular regulation of the calcium crosstalk between lysosomes and mitochondria, and explains PFOS-induced IR in the context of activated autophagy.


Assuntos
Ácidos Alcanossulfônicos , Autofagia , Cálcio , Fluorocarbonos , Resistência à Insulina , Fígado , Lisossomos , Mitocôndrias , ATPases Mitocondriais Próton-Translocadoras , Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Animais , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Autofagia/efeitos dos fármacos , Cálcio/metabolismo , Camundongos , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Masculino , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Linhagem Celular , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Poluentes Ambientais/toxicidade , Canais de Cátion TRPM/metabolismo , Camundongos Endogâmicos C57BL
11.
Ecotoxicol Environ Saf ; 280: 116553, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850699

RESUMO

The incidence of nonalcoholic steatohepatitis (NASH) is related with perfluorooctane sulfonate (PFOS), yet the mechanism remains ill-defined. Mounting evidence suggests that ferroptosis plays a crucial role in the initiation of NASH. In this study, we used mice and human hepatocytes L-02 to investigate the role of ferroptosis in PFOS-induced NASH and the effect and molecular mechanism of PFOS on liver ferroptosis. We found here that PFOS caused NASH in mice, and lipid accumulation and inflammatory response in the L-02 cells. PFOS induced hepatic ferroptosis in vivo and in vitro, as evidenced by the decrease in glutathione peroxidase 4 (GPX4), and the increases in cytosolic iron, acyl-CoA synthetase long-chain family member 4 (ACSL4) and lipid peroxidation. In the PFOS-treated cells, the increases in the inflammatory factors and lipid contents were reversed by ferroptosis inhibitor. PFOS-induced ferroptosis was relieved by autophagy inhibitor. The expression of mitochondrial calcium uniporter (MCU) was accelerated by PFOS, leading to subsequent mitochondrial calcium accumulation, and inhibiting autophagy reversed the increase in MCU. Inhibiting mitochondrial calcium reversed the variations in GPX4 and cytosolic iron, without influencing the change in ACSL4, induced by PFOS. MCU interacted with ACSL4 and the siRNA against MCU reversed the changes in ACSL4,GPX4 and cytosolic iron systemically. This study put forward the involvement of hepatic ferroptosis in PFOS-induced NASH and identified MCU as the mediator of the autophagy-dependent ferroptosis.


Assuntos
Ácidos Alcanossulfônicos , Autofagia , Cálcio , Coenzima A Ligases , Ferroptose , Fluorocarbonos , Hepatopatia Gordurosa não Alcoólica , Ferroptose/efeitos dos fármacos , Fluorocarbonos/toxicidade , Animais , Ácidos Alcanossulfônicos/toxicidade , Camundongos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/patologia , Autofagia/efeitos dos fármacos , Coenzima A Ligases/metabolismo , Humanos , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Linhagem Celular , Hepatócitos/efeitos dos fármacos
12.
Sensors (Basel) ; 24(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38475243

RESUMO

High-precision temperature control of large-area blackbodies has a pivotal role in temperature calibration and thermal imaging correction. Meanwhile, it is necessary to correct the temperature difference between the radiating (surface of use) and back surfaces (where the temperature sensor is installed) of the blackbody during the testing phase. Moreover, large-area blackbodies are usually composed of multiple temperature control channels, and manual correction in this scenario is error-prone and inefficient. At present, there is no method that can achieve temperature-automated calibration for a large-area blackbody radiation source. Therefore, this article is dedicated to achieving temperature-automated calibration for a large-area blackbody radiation source. First, utilizing two calibrated infrared thermometers, the optimal temperature measurement location was determined using a focusing algorithm. Then, a three-axis movement system was used to obtain the true temperature at the same measurement location on a large-area blackbody surface from different channels. This temperature was subtracted from the blackbody's back surface. The temperature difference was calculated employing a weighted algorithm to derive the parameters for calibration. Finally, regarding experimental verification, the consistency error of the temperature measurement point was reduced by 85.4%, the temperature uniformity of the surface source was improved by 40.4%, and the average temperature measurement deviation decreased by 43.8%. In addition, this system demonstrated the characteristics of strong environmental adaptability that was able to perform temperature calibration under the working conditions of a blackbody surface temperature from 100 K to 573 K, which decreased the calibration time by 9.82 times.

13.
J Am Chem Soc ; 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36763977

RESUMO

Noncatalytic gas-solid reactions are a large group of heterogeneous reactions that are usually assumed to occur irreversibly because of the strong driving force to favor the forward direction toward the product formation. Using the example of Ni oxidation into NiO with CO2, herein, we demonstrate the existence of the reverse element that results in the NiO reduction from the countering effect of the gaseous product of CO. Using in situ electron microscopy observations and atomistic modeling, we show that the oxidation process occurs via preferential CO2 adsorption along step edges that results in step-flow growth of NiO layers, and the presence of Ni atoms on the flat NiO surface promotes the nucleation of NiO layers. Simultaneously, the NiO reduction happens via preferential step-edge adsorption of CO that leads to the receding motion of atomic steps, and the presence of Ni vacancies in the NiO surface facilitates the CO-adsorption-induced surface pitting. Temperature and CO2 pressure effect maps are constructed to illustrate the spatiotemporal dynamics of the competing NiO redox reactions. These results demonstrate the rich gas-solid surface reaction dynamics induced by the coexisting forward and reverse reaction elements and have practical applicability in manipulating gas-solid reactions via controlling the gas environment or atomic structure of the solid surface to steer the reaction toward the desired direction.

14.
Funct Integr Genomics ; 23(2): 125, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060478

RESUMO

Although many genes may serve as reference genes, they may cause different expression patterns by selecting different reference genes because no single gene is expressed consistently in all tested tissues of an organism under all environmental and developmental conditions. Thus, it is becoming increasingly important and necessary to identify suitable reference genes before performing gene expression analysis. Currently, there are several computational tools available for evaluating the stability of candidate reference genes. These tools are based on different statistical algorithms and may produce different rankings in stability within the same reference gene study. To date, the RefFinder is the only web-based tool available for comparing and evaluating housekeeping genes as candidates to be reference genes. In this tool, we integrated the four currently available computational programs (geNorm, NormFinder, BestKeeper, and the comparative ΔCt method) into a web-based tool for evaluating the stability and reliability of reference genes. According to the gene stability rankings derived from the four programs, we assigned an appropriate weight to each gene and calculated the geometric mean of weights for the final rankings. Aside from the overall ranking, a single program or combination of the four programs can be selected for evaluating the ranking of candidate reference genes. This tool has been widely used and validated by many research laboratories around the world. You may use this tool at http://www.heartcure.com.au/reffinder/  or  https://blooge.cn/RefFinder/ . You can also download this algorithm program from https://github.com/fulxie/RefFinder and setup on your own computer. RefFinder is developed by PHP. Users can deploy it to a Php-based server (Apache + PHP) and run it.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase em Tempo Real/métodos , Perfilação da Expressão Gênica/métodos , Internet , Padrões de Referência
15.
Small ; 19(47): e2304384, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37480176

RESUMO

Responsive structural colors from artificially engineered micro/nanostructures are critical to the development of anti-counterfeiting, optical encryption, and intelligent display. Herein, the responsive structural color of hydrogel micropillar array is demonstrated under the external stimulus of ethanol vapor. Micropillar arrays with full color are fabricated via femtosecond laser direct writing by controlling the height and diameter of the micropillars according to the FDTD simulation. Color-switching of the micropillar arrays is achieved in <1 s due to the formation of liquid film among micropillars. More importantly, the structural color blueshift of the micropillar arrays is sensitive to the micropillar diameter, instead of the micropillar height. The micropillar array with a diameter of 772 nm takes 400 ms to complete blueshift under ethanol vapor, while that with a diameter of 522 nm blueshifts at 2400 ms. Microscale patterns are realized by employing the size-dependent color-switching of designed micropillar arrays under ethanol vapor. Moreover, Morse code and directional blueshift of structural colors are realized in the micropillar arrays. The advantages of controllable color-switching of the hydrogel micropillar array would be prospective in the areas of optical encryption, dynamic display, and anti-counterfeiting.

16.
Small ; 19(40): e2303166, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37264716

RESUMO

With the development of bionics as well as materials science, intelligent soft actuators have shown promising applications in many fields such as soft robotics, sensing, and remote manipulation. Microfabrication technologies have enabled the reduction of the size of responsive soft actuators to the micron level. However, it is still challenging to construct microscale actuators capable of responding to different external stimuli in complex and diverse conditions. Here, this work demonstrates a dual-stimuli cooperative responsive hydrogel microactuator by asymmetric fabrication via femtosecond laser direct writing. The dual response of the hydrogel microstructure is achieved by employing responsive hydrogel with functional monomer 2-(dimethylamino)ethyl methacrylate. Raman spectra of the hydrogel microstructures suggest that the pH and temperature response of the hydrogel is generated by the changes in tertiary amine groups and hydrogen bonds, respectively. The asymmetric hydrogel microstructures show opposite bending direction when being heated to high temperature or exposed to acid solution, and can independently accomplish the grasp of polystyrene microspheres. Moreover, this work depicts the cooperative response of the hydrogel microactuator to pH and temperature at the same time. The dual-stimuli cooperative responsive hydrogel microactuators will provide a strategy for designing and fabricating controllable microscale actuators with promising applications in microrobotics and microfluidics.

17.
Plant Physiol ; 190(4): 2430-2448, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36053177

RESUMO

Cucurbitales are an important order of flowering plants known for encompassing edible plants of economic and medicinal value and numerous ornamental plants of horticultural value. By reanalyzing the genomes of two representative families (Cucurbitaceae and Begoniaceae) in Cucurbitales, we found that the previously identified Cucurbitaceae common paleotetraploidization that occurred shortly after the core-eudicot-common hexaploidization event is shared by Cucurbitales, including Begoniaceae. We built a multigenome alignment framework for Cucurbitales by identifying orthologs and paralogs and systematically redating key evolutionary events in Cucurbitales. Notably, characterizing the gene retention levels and genomic fractionation patterns between subgenomes generated from different polyploidizations in Cucurbitales suggested the autopolyploid nature of the Begoniaceae common tetraploidization and the allopolyploid nature of the Cucurbitales common tetraploidization and the Cucurbita-specific tetraploidization. Moreover, we constructed the ancestral Cucurbitales karyotype comprising 17 proto-chromosomes, confirming that the most recent common ancestor of Cucurbitaceae contained 15 proto-chromosomes and rejecting the previous hypothesis for an ancestral Cucurbitaceae karyotype with 12 proto-chromosomes. In addition, we found that the polyploidization and tandem duplication events promoted the expansion of gene families involved in the cucurbitacin biosynthesis pathway; however, gene loss and chromosomal rearrangements likely limited the expansion of these gene families.


Assuntos
Cucurbitaceae , Magnoliopsida , Genoma de Planta/genética , Evolução Molecular , Filogenia , Magnoliopsida/genética , Cucurbitaceae/genética , Poliploidia
18.
Opt Express ; 31(17): 28320-28337, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710889

RESUMO

To realize deep space optical communications with high capacity and sensitivity, synchronization of pulse-position modulation (PPM) signals is crucial. In this study, the maximum likelihood synchronization algorithm based on inter-symbol guard times was generalized to the scenario with strong blockage of single-photon detectors, where higher PPM slot frequency and signal-noise ratio could be adopted. Furthermore, a slot frequency offset compensation method was proposed, and simulations and experiments were performed to verify the performance improvement of the proposed corrected synchronization algorithm under blockage. The results indicated that the deadtime-corrected synchronization scheme could effectively overcome the performance degradation of the original model under high photon flux, provide estimation (0.02749 slots @ root-mean-square error) close to the Cramér-Rao Bound, and error rates close to ideal synchronization in the experiment.

19.
Cell Commun Signal ; 21(1): 248, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735657

RESUMO

BACKGROUND: Exosomes are a new class of molecular entities in the metastatic microenvironment, which can mediate bidirectional communication between cells. While exosomes-mediated interactions between tumor cells and other cell populations in the tumor microenvironment have attracted most attention, little is known about the significance of exosomes in mediating the interaction between non-stemness cancer cells and cancer stem cells during cancer progression. METHODS: The structure, sequence and downstream target miRNAs of lncRNA Mir100hg were predicted by online web resources. The bioinformatics prediction results were validated with experimental verification: exosome tracing, electron microscopy, Luciferase assay, metabolomics sequencing and mouse tail vein model of pulmonary metastasis. A complex regulatory network of "cancer stem cells-exosomal lncRNA-non-stem cancer cells" was constructed. RESULTS: This study demonstrates firstly that lncRNA Mir100hg is upregulated in lung cancer stem cell LLC-SD (Lung cancer stem cells) and can be delivered to non-stemness cancer cells LLC (Lewis lung cancer cells) via exosomes. In LLC, Mir100hg targets miR-15a-5p and miR-31-5p which leads to the increase of the global glycolytic activity of lung cancer cells and consequently, the enhancement of their metastatic capability. CONCLUSION: We delineated a complex regulatory network that utilized by cancer stem cells to transfer their high metastatic activity to the low-metastatic non-stemness cancer cells through exosomal Mir100hg, thereby providing new mechanistic insights into the communication between two heterogeneous tumor cells. Video Abstract.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Animais , Camundongos , RNA Longo não Codificante/genética , Neoplasias Pulmonares/genética , Modelos Animais de Doenças , Glicólise , MicroRNAs/genética , Células-Tronco Neoplásicas , Pulmão , Microambiente Tumoral
20.
Pharmacol Res ; 188: 106660, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36642112

RESUMO

Despite the unprecedented advancement of cancer treatment, the prognosis for patients with metastatic stage of cancer remains poor. The challenge that underlines this clinical dilemma is the complexity of metastasis. The conventional experiment-driven discovery approaches (the "wet lab") yield overly simplified one-to-one mechanistic relationships that are inept of elucidating the complexity of metastasis. Metastasis research also suffers from the knowledge and skill deficiency of the individual investigators. The importance of the present study is the demonstration that the "dry-lab-driven discovery and wet-lab validation" approach can improve the efficiency of studying complex biological behaviors, and can yield more reliable, objective and comprehensive mechanistic findings that are have clinical significance. Specifically, we applied this approach to study the mechanisms that underline the involvement of exosomal miRNAs in transferring the metastatic capability between heterogenous melanoma cancer cells. We show that the highly metastatic melanoma tumor cells (POL) can transfer their metastatic competency to the low-metastatic melanoma tumor cells (OL) by exosomal miR-211-5p. The oncogenic activity of miR-211-5p is mediated by the target gene guanine nucleotide-binding protein subunit alpha-15 (GNA15) through modifying the immune function of the tumor microenvironment extrinsically; as well as through inhibiting pyroptosis and augmenting glycolysis within OL cells intrinsically. In addition, we show that exosomal sorting of miR-211-5p is like selective and is subjected to regulation by a transcriptional feedback loop between miR-211-5p and zinc finger FYVE-type containing 26 (ZFYVE26). Furthermore, the "8-genes pyroptosis Risk model" derived from LASSO regression analysis was verified as an independent prognostic factor for melanoma.


Assuntos
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP , Melanoma , MicroRNAs , Microambiente Tumoral , Humanos , Glucose , Melanoma/metabolismo , Melanoma/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico , Piroptose , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo
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