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1.
Nature ; 594(7861): 41-45, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34079139

RESUMO

Owing to the inevitable loss in communication channels, the distance of entanglement distribution is limited to approximately 100 kilometres on the ground1. Quantum repeaters can circumvent this problem by using quantum memory and entanglement swapping2. As the elementary link of a quantum repeater, the heralded distribution of two-party entanglement between two remote nodes has only been realized with built-in-type quantum memories3-9. These schemes suffer from the trade-off between multiplexing capacity and deterministic properties and hence hinder the development of efficient quantum repeaters. Quantum repeaters based on absorptive quantum memories can overcome such limitations because they separate the quantum memories and the quantum light sources. Here we present an experimental demonstration of heralded entanglement between absorptive quantum memories. We build two nodes separated by 3.5 metres, each containing a polarization-entangled photon-pair source and a solid-state quantum memory with bandwidth up to 1 gigahertz. A joint Bell-state measurement in the middle station heralds the successful distribution of maximally entangled states between the two quantum memories with a fidelity of 80.4 ± 2.2 per cent (±1 standard deviation). The quantum nodes and channels demonstrated here can serve as an elementary link of a quantum repeater. Moreover, the wideband absorptive quantum memories used in the nodes are compatible with deterministic entanglement sources and can simultaneously support multiplexing, which paves the way for the construction of practical solid-state quantum repeaters and high-speed quantum networks.

2.
Langmuir ; 40(26): 13721-13727, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38899455

RESUMO

Optical tweezers (OT) have evolved into powerful single molecule force spectroscopy tools to investigate protein folding-unfolding dynamics. To stretch a protein of interest using OT, the protein must be flanked with two double stranded DNA (dsDNA) handles. However, coupling dsDNA handles to the protein is often of low yield, representing a bottleneck in OT experiments. Here, we report a handle-free, all-protein-based OT method for investigating protein folding/unfolding dynamics. In this new method, we employed disordered elastin-like polypeptides (ELPs) as a molecular linker and the mechanically stable cohesin-dockerin (Coh-Doc) pair as the prey-bait system to enable the efficient capture and stretching of individual protein molecules. This novel approach was validated by using model proteins NuG2 and RTX-v, yielding experimental results comparable to those obtained by using the dsDNA handle approach. This new method provides a streamlined and efficient OT approach to investigate the folding-unfolding dynamics of proteins at the single molecule level, thus expanding the toolbox of OT-based single molecule force spectroscopy.


Assuntos
Pinças Ópticas , Dobramento de Proteína , DNA/química , Desdobramento de Proteína , Peptídeos/química , Proteínas/química
3.
Blood Purif ; : 1-18, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39265561

RESUMO

INTRODUCTION: Hypophosphatemia is a common and potentially severe complication of continuous kidney replacement therapy (CKRT), but the evidence on the correlation between hypophosphatemia occurring during CKRT and clinical outcomes remains limited. METHODS: Electronic databases (PubMed, Embase, Web of Science, and the Cochrane database) were searched from inception to March 1, 2024. All possible studies that examined the following outcomes were included: all-cause mortality, mechanical ventilation, intensive care unit (ICU) stay, and CKRT duration. RESULTS: A total of 8,631 patients from eight cohort studies were included. There was no statistical association between hypophosphatemia during CKRT and all-cause mortality in critically ill patients (OR 0.82, 95% CI 0.57-1.18, P =0.28, I2 = 83%). However, hypophosphatemia was associated with longer duration of mechanical ventilation (WMD 80.30h, 95% CI 31.37-129.22, P =0.001, I2 = 60%). Furthermore, a longer length of ICU stay (WMD 2.76d, 95% CI 2.50-3.02, P <0.00001, I2 = 36%) and CKRT duration (WMD 51.51h, 95% CI 2.69-100.34, P =0.04, I2 = 96%) were observed in patients with hypophosphatemia. CONCLUSIONS: The association between hypophosphatemia and mortality in patients receiving CKRT was insufficient. However, hypophosphatemia during CKRT might be associated with adverse clinical outcomes for critically ill patients.

4.
Angew Chem Int Ed Engl ; 63(6): e202313260, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37938169

RESUMO

Conjugated polymers that can efficiently transport both ionic and electronic charges have broad applications in next-generation optoelectronic, bioelectronic, and energy storage devices. To date, almost all the conjugated polymers have hydrophobic backbones, which impedes efficient ion diffusion/transport in aqueous media. Here, we design and synthesize a novel hydrophilic polymer building block, 4a-azonia-naphthalene (AN), drawing inspiration from biological systems. Because of the strong electron-withdrawing ability of AN, the AN-based polymers show typical n-type charge transport behaviors. We find that cationic aromatics exhibit strong cation-π interactions, leading to smaller π-π stacking distance, interesting ion diffusion behavior, and good morphology stability. Additionally, AN enhances the hydrophilicity and ionic-electronic coupling of the polymer, which can help to improve ion diffusion/injection speed, and operational stability of organic electrochemical transistors (OECTs). The integration of cationic building blocks will undoubtedly enrich the material library for high-performance n-type conjugated polymers.

5.
Ren Fail ; 45(2): 2258986, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37724564

RESUMO

BACKGROUND: Renal anemia, a common complication and threat factor of chronic kidney disease (CKD), has long been treated with injectable erythropoietin-stimulating agents (ESAs). As concerns regarding cardiovascular safety and erythropoietin resistance to ESAs have emerged, alternative therapies are urgently needed. Hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), an oral agent, has been proven to be effective in improving renal anemia. However, the effects of HIF-PHIs on nondialysis-dependent CKD (NDD-CKD) have yet to be supported by updated meta-analyses. METHODS: A meta-analysis of clinical randomized controlled trials (RCTs) on HIF-PHI treatment of NDD-CKD patients based on PubMed, EMBASE, and Cochrane databases as of July 16th, 2023, was conducted. The primary outcomes were the level of hemoglobin (Hb) postintervention and the ratio of Hb responses. Most of the analysis was conducted via RevMan 5.3 software using a random-effects model. Stata (version 15.0) was used to analyze the publication bias. RESULTS: Twenty-two studies with a total of 7178 subjects in the HIF-PHI group, 3501 subjects in the ESA group and 2533 subjects in the placebo group were enrolled. HIF-PHIs increased the level of Hb and improved iron metabolism but were not inferior to ESAs in terms of safety. CONCLUSIONS: HIF-PHIs may be a convenient and safe alternative to ESAs in patients with NDD-CKD and anemia.


Assuntos
Anemia , Eritropoetina , Inibidores de Prolil-Hidrolase , Insuficiência Renal Crônica , Humanos , Anemia/tratamento farmacológico , Anemia/etiologia , Epoetina alfa , Eritropoetina/efeitos adversos , Hipóxia , Prolil Hidroxilases , Inibidores de Prolil-Hidrolase/efeitos adversos , Insuficiência Renal Crônica/complicações
6.
Phys Rev Lett ; 129(21): 210501, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461974

RESUMO

Quantum memories at telecom wavelengths are crucial for the construction of large-scale quantum networks based on existing fiber networks. On-demand storage of telecom photonic qubits is an essential request for such networking applications but yet to be demonstrated. Here we demonstrate the storage and on-demand retrieval of telecom photonic qubits using a laser-written waveguide fabricated in an ^{167}Er^{3+}:Y_{2}SiO_{5} crystal. Both ends of the waveguide memory are directly connected with fiber arrays with a fiber-to-fiber efficiency of 51%. Storage fidelity of 98.3(1)% can be obtained for time-bin qubits encoded with single-photon-level coherent pulses, which is far beyond the maximal fidelity that can be achieved with a classical measure and prepared strategy. This device features high reliability and easy scalability, and it can be directly integrated into fiber networks, which could play an essential role in fiber-based quantum networks.

7.
Sensors (Basel) ; 22(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35890770

RESUMO

When approaching and removing a disabled satellite, the accuracy of the controller is imperative to the success of the mission because if the mission fails, more space debris can be produced due to satellite collision. To address this issue, a controller directly driven by discrete sample data points is proposed in this paper. First, the input vector for the controller is placed into a state space as a point. The state space also contains points constructed by the input vectors of pre-generated samples, which are created by the GPOPS planning algorithm along with control commands as sample output vectors. Then, an adjacent range is selected and the sample points within are collected. To accelerate the process, a series of data processing methods are implemented, including the dichotomy method, table look-up method, and random selection method. Finally, the control commands are computed using the iteratively reweighted least-squares algorithm with the assumption that similar inputs have similar outputs. According to the simulation results, the discrete point controller is more precise than the neural network controller.

8.
Sensors (Basel) ; 22(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35458978

RESUMO

Recently, remote sensing satellites have become increasingly important in the Earth observation field as their temporal, spatial, and spectral resolutions have improved. Subsequently, the quantitative evaluation of remote sensing satellites has received considerable attention. The quantitative evaluation method is conventionally based on simulation, but it has a speed-accuracy trade-off. In this paper, a real-time evaluation model architecture for remote sensing satellite clusters is proposed. Firstly, a multi-physical field coupling simulation model of the satellite cluster to observe moving targets is established. Aside from considering the repercussions of on-board resource constraints, it also considers the consequences of the imaging's uncertainty effects on observation results. Secondly, a moving target observation indicator system is developed, which reflects the satellite cluster's actual effectiveness in orbit. Meanwhile, an indicator screening method using correlation analysis is proposed to improve the independence of the indicator system. Thirdly, a neural network is designed and trained for stakeholders to realize a rapid evaluation. Different network structures and parameters are comprehensively studied to determine the optimized neural network model. Finally, based on the experiments carried out, the proposed neural network evaluation model can generate real-time, high-quality evaluation results. Hence, the validity of our proposed approach is substantiated.

9.
Ren Fail ; 42(1): 77-88, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31893969

RESUMO

Purpose: The results from randomized controlled trials (RCTs) concerning the timing of initiation of renal replacement therapy (RRT) for patients with acute kidney injury (AKI) are still inconsistent.Materials and methods: We searched for RCTs, as well as relevant references, focusing on the timing of RRT for AKI patients in the Medline, Embase, Cochrane Library, Google Scholar and Chinese databases from their inception to December 2018.Results: We included 18 RCTs from 1997 to 2018 involving 2856 patients. Pooled analyses of all RCTs showed no significant difference in mortality between early initiation and delayed initiation of RRT (RR 0.98, 95% CI: 0.89 to 1.08, p = .7) (I2 = 2%), and similar results were found in critically ill and community-acquired AKI patients, as well as in a subgroup of patients with sepsis and in cardiac surgery recipients. There was also no difference in the incidence of dialysis independence (RR 0.75, 95% CI: 0.47 to 1.2, p = .2) (I2 = 0). However, an early RRT strategy was associated with a significantly higher incidence of the need for RRT for AKI patients (RR 1.24, 95% CI: 1.13 to 1.36, p < .01) (I2 = 34%).Conclusions: As no life-threatening complications occurred, there was no evidence to show any benefit of an early RRT strategy for critically ill or community-acquired AKI patients; in contrast, a delayed strategy might avert the need for RRT.


Assuntos
Injúria Renal Aguda/terapia , Terapia de Substituição Renal/normas , Tempo para o Tratamento/normas , Estado Terminal/terapia , Humanos , Incidência , Guias de Prática Clínica como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Resultado do Tratamento
10.
Molecules ; 25(4)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079147

RESUMO

The purpose of this research was to explore the fresh keeping effect of modified atmosphere packaging (MAP) with different gas ratios combined with gelatin active coatings containing eugenol on Chinese sea bass stored at -0.9 °C for 36 days. The results showed that MAP3 (60% CO2/10% O2/30% N2), together with gelatin active coatings containing eugenol, could prevent water loss, which maintained high field NMR, MRI, and organoleptic evaluation results. This hurdle technology could also effectively delay the bacterial reproduction, protein degradation, and alkaline accumulation, so it showed the lowest K value, total volatile basic nitrogen, free amino acids, total viable count, Pseudomonas spp., and H2S-producing bacteria, which better maintain the quality of sea bass.


Assuntos
Atmosfera , Dióxido de Carbono/química , Eugenol/química , Embalagem de Alimentos , Conservação de Alimentos , Gelatina/química , Refrigeração , Animais , Bactérias/crescimento & desenvolvimento , Bass/microbiologia , Contagem de Colônia Microbiana , Cor , Elasticidade , Contaminação de Alimentos , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Imageamento por Ressonância Magnética , Muco/química , Músculos/anatomia & histologia , Nitrogênio/análise , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Volatilização , Água
11.
Blood Purif ; 48(1): 10-17, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30844791

RESUMO

BACKGROUND: To determine the optimal time for discontinuing continuous renal replacement therapy (CRRT) by evaluating serum neutrophil gelatinase-associated lipocalin (NGAL) in critically ill patients with acute kidney injury (AKI). METHODS: A prospective observational study was conducted from September 2015 to March 2018. AKI patients treated with CRRT for at least 24 h were divided into "success" and "failure" groups according to their RRT requirement within 7 days after the initial discontinuation of CRRT. The prefilter and effluent NGAL concentrations were measured to calculate the sieving coefficient (SC) of NGAL in all included subjects from 0 to 72 h. RESULTS: In total, 110 patients were divided into success (n = 78) and failure groups (n = 32). The mean SC of NGAL during CRRT was less than 0.05. The patients in the failure group were associated with higher mortality compared with patients in the success group (37.5 vs. 12.8%, respectively, p = 0.013). There were significant differences in serum NGAL, creatinine, and urine output at discontinuation. In patients without sepsis (n = 70), serum NGAL and urine output were significant predictors of successful cessation. The area under the receiver operating characteristic to predict the successful discontinuation of CRRT was 0.88 for NGAL and 0.86 for urine output. An NGAL level of 403 ng/mL had the highest sensitivity (81%) and specificity (89%) and a urine output of 695 mL/day had the highest sensitivity (83%) and specificity (88%). However, in septic patients (n = 40), urine output but not serum NGAL (OR 0.999, p = 0.69) was a significant variable (OR 1.002, p = 0.005), with a cutoff of 796 mL/day (sensitivity 83%, specificity 88%). CONCLUSIONS: Serum NGAL was a significant factor for predicting successful CRRT discontinuation in nonseptic AKI patients. However, urine output, rather than serum NGAL, was a significant predictor in septic AKI patients.


Assuntos
Injúria Renal Aguda/sangue , Injúria Renal Aguda/terapia , Terapia de Substituição Renal Contínua , Estado Terminal , Lipocalina-2/sangue , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/mortalidade , Adulto , Idoso , Biomarcadores , Tomada de Decisão Clínica , Terapia de Substituição Renal Contínua/efeitos adversos , Terapia de Substituição Renal Contínua/métodos , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Razão de Chances , Prognóstico , Curva ROC , Resultado do Tratamento
12.
Small ; 13(44)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28961386

RESUMO

Freestanding, flexible/foldable, and wearable bifuctional ultrathin graphene paper for heating and cooling is fabricated as an active material in personal thermal management (PTM). The promising electrical conductivity grants the superior Joule heating for extra warmth of 42 °C using a low supply voltage around 3.2 V. Besides, based on its high out-of-plane thermal conductivity, the graphene paper provides passive cooling via thermal transmission from the human body to the environment within 7 s. The cooling effect of graphene paper is superior compared with that of the normal cotton fiber, and this advantage will become more prominent with the increased thickness difference. The present bifunctional graphene paper possesses high durability against bending cycles over 500 times and wash time over 1500 min, suggesting its great potential in wearable PTM.

13.
Food Chem ; 460(Pt 1): 140555, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39047490

RESUMO

To further reveal the inhibition mechanism of carbon dioxide (CO2) on Shewanella putrefaciens (S. putrefaciens), influence on metabolic function was studied by biochemical and metabolomics analysis. Accordingly, reduction of intracellular pH (pHi), depolarization of cell membrane and accumulation of reactive oxygen species (ROS) indicated that CO2 changed the membrane permeability of S. putrefaciens. Besides, adenosine triphosphate (ATP), ATPase, nicotinamide adenine dinucleotide (NAD+/NADH) and ratios of NADH/NAD+ were detected, indicating a role of CO2 in repressing respiratory pathway and electron transport. According to metabolomics results, CO2 induced differential expressions of metabolites, disordered respiratory chain and weakened energy metabolism of S. putrefaciens. Inhibition of respiratory rate-limiting enzymes also revealed that electron transfer of respiratory chain was blocked, cell respiration was weakened, and thus energy supply was insufficient under CO2 stress. These results revealed that CO2 caused disruption of metabolic function, which might be the main cause of growth inhibition for S. putrefaciens.


Assuntos
Antibacterianos , Dióxido de Carbono , Metabolômica , Shewanella putrefaciens , Shewanella putrefaciens/metabolismo , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Trifosfato de Adenosina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NAD/metabolismo , Transporte de Elétrons
14.
J Agric Food Chem ; 72(31): 17559-17571, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39054619

RESUMO

To explore whether oxidative stress caused by 100% CO2 is an inhibitory mechanism against Shewanella putrefaciens, the oxidative stress reaction, antioxidant activity, and damage to the cell membrane, protein, and DNA of CO2-incubated S. putrefaciens at 4 °C were evaluated. Research demonstrated that CO2 caused more severe reactive oxygen species (ROS) accumulation. Simultaneously, weaker •OH/H2O2/O2•--scavenging activity and decreased T-VOC and GSH content were also observed. The activities of antioxidant enzymes (SOD, POD, CAT, and GPX) continuously declined, which might be attributed to the CO2-mediated decrease in the pH value. Correspondingly, the cell membrane was damaged with hyperpolarization, increased permeability, and more severe lipid peroxidation. The expression of total and membrane protein decreased, and the synthesis and activity of extracellular protease were inhibited. DNA was also subjected to oxidative damage and expressed at a lower level. All results collaboratively confirmed that ROS excitation and inhibition of antioxidant activity were important inhibition mechanisms of CO2 on S. putrefaciens.


Assuntos
Dióxido de Carbono , Membrana Celular , Estresse Oxidativo , Espécies Reativas de Oxigênio , Shewanella putrefaciens , Shewanella putrefaciens/metabolismo , Shewanella putrefaciens/genética , Espécies Reativas de Oxigênio/metabolismo , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Dióxido de Carbono/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Antioxidantes/metabolismo , Dano ao DNA/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , DNA Bacteriano/metabolismo , DNA Bacteriano/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética
15.
Neurosci Lett ; 842: 137997, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39326778

RESUMO

Visual system is the most important system of animal to cognize the information in outside world, and reward-related visual cues are the key factors in the consolidation and retrieval of reward memory. However, the neural circuit mechanism is still unclear. Superior Colliculus (SC) receive direct input from the retina and belong to the earliest stages of visual processing. Recent studies identified a specific pathway from SC to ventral tegmental area (VTA) that underlie specific innate behaviors, eg. flight or freezing, approach behaviors and so on. In present research, we investigated that inhibition of SC to VTA circuit with chemogenetics suppressed light cue-associated reward-seeking behaviors, while activation of the SC-VTA circuit with chemogenetic technology triggered the reward-seeking behaviors in optical intracranial self-stimulation for VTA DA neurons (oICSS) in mice. These findings suggest that neural circuit of SC-VTA mediates the retrieval of reward memory associated with visual cues, which will provide a new field for revealing the neural mechanism of pathological memory such as addiction.

16.
Micromachines (Basel) ; 15(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38675318

RESUMO

Arterial stiffness has been proved to be an important parameter in the evaluation of cardiovascular diseases, and Pulse Wave Velocity (PWV) is a strong indicator of arterial stiffness. Compared to regional PWV (PWV among different arteries), local PWV (PWV within a single artery) outstands in providing higher precision in indicating arterial properties, as regional PWVs are highly affected by multiple parameters, e.g., variations in blood vessel lengths due to individual differences, and multiple reflection effects on the pulse waveform. However, local PWV is less-developed due to its high dependency on the temporal resolution in synchronized signals with usually low signal-to-noise ratios. This paper presents a method for the noninvasive simultaneous measurement of two local PWVs in both left and right radial arteries based on the Fiber Bragg Grating (FBG) technique via correlation analysis of the pulse pairs at the fossa cubitalis and at the wrist. Based on the measurements of five male volunteers at the ages of 19 to 21 years old, the average left radial PWV ranged from 9.44 m/s to 12.35 m/s and the average right radial PWV ranged from 11.50 m/s to 14.83 m/s. What is worth mentioning is that a stable difference between the left and right radial PWVs was observed for each volunteer, ranging from 2.27 m/s to 3.04 m/s. This method enables the dynamic analysis of local PWVs and analysis of their features among different arteries, which will benefit the diagnosis of early-stage arterial stiffening and may bring more insights into the diagnosis of cardiovascular diseases.

17.
Foods ; 13(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38790808

RESUMO

α-Dicarbonyl compounds (α-DCs) are commonly present in various foods. We conducted the investigation into concentration changes of α-DCs including 3-deoxyglucosone (3-DG), glyoxal (GO), and methylglyoxal (MGO) in fresh fruits and decapped commercial juices during storage at room temperature and 4 °C, as well as in homemade juices during storage at 4 °C. The studies indicate the presence of α-DCs in all samples. The initial contents of 3-DG in the commercial juices (6.74 to 65.61 µg/mL) are higher than those in the homemade ones (1.97 to 4.65 µg/mL) as well as fruits (1.58 to 3.33 µg/g). The initial concentrations of GO and MGO are normally less than 1 µg/mL in all samples. During storage, the α-DC levels in the fruits exhibit an initial increase followed by a subsequent decrease, whereas, in all juices, they tend to accumulate continuously over time. As expected, 4 °C storage reduces the increase rates of the α-DC concentrations in most samples. From the viewpoint of the α-DC contents, fruits and homemade juices should always be the first choice for daily intake of nutrients and commercial juices ought to be mostly avoided.

18.
Front Aging Neurosci ; 16: 1392304, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863782

RESUMO

Background: Age-related decline in cognitive function is often linked to changed prefrontal cortex (PFC) activity and heart rate variability (HRV). Mild cognitive impairment (MCI), a transitional stage between normal aging and dementia, might have further degeneration beyond aging. This study aimed to investigate the differences between young and older adults with or without MCI in cognitive functions, task-induced PFC activation and HRV changes. Methods: Thirty-one healthy young adults (YA), 44 older adults (OA), and 28 older adults with MCI (OA-MCI) were enrolled and compared in this cross-sectional study. Each participant received a one-time assessment including cognitive and executive functions, as well as the simultaneous recording of PFC activity and HRV during a cognitive task paradigm. Results: We observed age-related decrease in global cognitive functions, executive functions, HRV, and increase in PFC activity. The MCI further deteriorated the global cognitive and executive performances, but not the HRV or the prefrontal activation. Conclusion: Older people showed lower performances in general cognitive function and executive function, compensatory increase of PFC activity, and reduced HRV. Older people with MCI had further deterioration in cognitive performance, but not in PFC activation and HRV.

19.
Nat Commun ; 15(1): 8529, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39358375

RESUMO

Quantum networks provide a prospective paradigm to connect separated quantum nodes, which relies on the distribution of long-distance entanglement and active feedforward control of qubits between remote nodes. Such approaches can be utilized to construct nonlocal quantum gates, forming building blocks for distributed quantum computing and other novel quantum applications. However, these gates have only been realized within single nodes or between nodes separated by a few tens of meters, limiting the ability to harness computing resources in large-scale quantum networks. Here, we demonstrate nonlocal photonic quantum gates between two nodes spatially separated by 7.0 km using stationary qubits based on multiplexed quantum memories, flying qubits at telecom wavelengths, and active feedforward control based on field-deployed fibers. Furthermore, we illustrate quantum parallelism by implementing the Deutsch-Jozsa algorithm and the quantum phase estimation algorithm between the two remote nodes. These results represent a proof-of-principle demonstration of quantum gates over metropolitan-scale distances and lay the foundation for the construction of large-scale distributed quantum networks relying on existing fiber channels.

20.
Adv Mater ; 36(24): e2400287, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38433667

RESUMO

Organic electrochemical transistors (OECTs) have attracted increasing attention due to their merits of high transconductance, low operating voltage, and good biocompatibility, ideal for biosensors. However, further advances in their practical applications face challenges of low n-type performance and poor stability. Here, it is demonstrated that wet-spinning the commercially available n-type conjugated polymer poly(benzimidazobenzophenanthroline) (BBL) into highly aligned and crystalline fibers enhances both OECT performance and stability. Although BBL is only soluble in high-boiling-point strong acids, it can be wet-spun into high-quality fibers with adjustable diameters. The BBL fiber OECTs exhibit a record-high area-normalized transconductance (gm,A) of 2.40 µS µm-2 and over 10 times higher figure-of-merit (µC*) than its thin-film counterparts. More importantly, these fiber OECTs exhibit remarkable stability with no noticeable performance attenuation after 1500 cycles over 4 h operation, outperforming all previously reported n-type OECTs. The superior performance and stability can be attributed to shorter π-π stacking distance and ordered molecular arrangement in the fibers, endowing the BBL fiber OECT-based biosensors with outstanding sensitivity while keeping a miniaturized form factor. This work demonstrates that, beyond new material development, developing new fabrication technology is also crucial for addressing the performance and stability issues in n-type OECTs.

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