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1.
Nanotechnology ; 35(36)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38861939

RESUMEN

Surface plasmonic detectors have the potential to be key components of miniaturized chip-scale spectrometers. Graphene plasmons, which are highly confined and gate-tunable, are suitable forin situlight detection. However, the tuning of graphene plasmonic photodetectors typically relies on the complex and high operating voltage based on traditional dielectric gating technique, which hinders the goal of miniaturized and low-power consumption spectrometers. In this work, we report a tunable mid-infrared (MIR) photodetector by integrating of patterned graphene with non-volatile ferroelectric polarization. The polarized ferroelectric thin film provides an ultra-high surface electric field, allowing the Fermi energy of the graphene to be manipulated to the desired level, thereby exciting the surface plasmon polaritons effect, which is highly dependent on the free carrier density of the material. By exciting intrinsic graphene plasmons, the light transmittance of graphene is greatly enhanced, which improves the photoelectric conversion efficiency of the device. Additionally, the electric field on the surface of graphene enhanced by the graphene plasmons accelerates the carrier transfer efficiency. Therefore, the responsivity of the device is greatly improved. Our simulations show that the detectors have a tunable resonant spectral response of 9-14µm by reconstructing the ferroelectric domain and exhibit a high responsivity to 5.67 × 105A W-1at room temperature. Furthermore, we also demonstrate the conceptual design of photodetector could be used for MIR micro-spectrometer application.

2.
Cell Mol Biol Lett ; 29(1): 68, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730334

RESUMEN

BACKGROUND: Members of the nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing (NLRP) family regulate various physiological and pathological processes. However, none have been shown to regulate actin cap formation or spindle translocation during the asymmetric division of oocyte meiosis I. NLRP4E has been reported as a candidate protein in female fertility, but its function is unknown. METHODS: Immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR), and western blotting were employed to examine the localization and expression levels of NLRP4E and related proteins in mouse oocytes. small interfering RNA (siRNA) and antibody transfection were used to knock down NLRP4E and other proteins. Immunoprecipitation (IP)-mass spectrometry was used to identify the potential proteins interacting with NLRP4E. Coimmunoprecipitation (Co-IP) was used to verify the protein interactions. Wild type (WT) or mutant NLRP4E messenger RNA (mRNA) was injected into oocytes for rescue experiments. In vitro phosphorylation was employed to examine the activation of steroid receptor coactivator (SRC) by NLRP4E. RESULTS: NLRP4E was more predominant within oocytes compared with other NLRP4 members. NLRP4E knockdown significantly inhibited actin cap formation and spindle translocation toward the cap region, resulting in the failure of polar body extrusion at the end of meiosis I. Mechanistically, GRIN1, and GANO1 activated NLRP4E by phosphorylation at Ser429 and Thr430; p-NLRP4E is translocated and is accumulated in the actin cap region during spindle translocation. Next, we found that p-NLRP4E directly phosphorylated SRC at Tyr418, while p-SRC negatively regulated p-CDC42-S71, an inactive form of CDC42 that promotes actin cap formation and spindle translocation in the GTP-bound form. CONCLUSIONS: NLRP4E activated by GRIN1 and GANO1 regulates actin cap formation and spindle translocation toward the cap region through upregulation of p-SRC-Tyr418 and downregulation of p-CDC42-S71 during meiosis I.


Asunto(s)
Actinas , Meiosis , Oocitos , Proteína de Unión al GTP cdc42 , Animales , Oocitos/metabolismo , Ratones , Femenino , Actinas/metabolismo , Actinas/genética , Proteína de Unión al GTP cdc42/metabolismo , Proteína de Unión al GTP cdc42/genética , Fosforilación , Huso Acromático/metabolismo
3.
Nucleic Acids Res ; 50(5): e26, 2022 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-35191504

RESUMEN

Alternative polyadenylation (APA) plays an important role in gene regulation. With the recent application of novel sequencing technology in APA profiling, an ever-increasing number of APA genes/sites have been identified. However, the phenotypic relevance of most of these APA isoforms remains elusive, which is largely due to the lack of a convenient genetics tool for APA interference. To address this issue, herein, an efficient method is developed based on the CRISPR-dCas13 system, termed as CRISPR-iPAS. Out of eight different dCas13 proteins, Porphyromonas gulae (Pgu) dCas13b, is identified as the most effective one in blocking the usage of the polyadenylation site (PAS). With guide RNAs targeting at core regulatory elements, dPguCas13b enabled APA regulation of endogenous genes with different APA types, including tandem 3'UTR, alternative terminal exon, as well as intronic PAS. Finally, we demonstrated that the proposed APA perturbation tool could be used to investigate the functional relevance of APA isoforms.


Asunto(s)
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Técnicas Genéticas , Poliadenilación , Regiones no Traducidas 3' , Regulación de la Expresión Génica , Intrones/genética
4.
BMC Cancer ; 23(1): 707, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507669

RESUMEN

BACKGROUND: Circulating tumor cells (CTCs) have been a non-invasive technique which allows investigation of tumor characteristics. The purpose of this study was to investigate the relationship between circulating tumor cells and colorectal cancer. METHODS: The clinical data of 617 patients with colorectal cancer from October 2019 to March 2022 were retrospectively collected to analyze the correlation between CTCs and clinicopathologic characteristics. RESULTS: The CTCs value increased with the progression of Tumor(T) stage,Metastasis(M) stage and Tumor Node Metastasis(TNM) stage (P < 0.05), but not with Node (N) stage (P > 0.05). Binary logistic regression analysis showed that CTCs, CEA, CA125 and CA199 were independent risk factors for CRC metastasis. Compared with CTCs, CEA, CA125 and CA199, the Logistic model had the highest AUC (AUC = 0.778,95%CI: 0.732-0.824), and the specificity and sensitivity were 82.9% and 63.2%, respectively. After operation, chemo-radiotherapy and other treatment for CRC, CTCs and CEA were significantly decreased compared with before treatment (P < 0.05). In addition, Spearman Correlation showed significant correlation between CTCs and IgG (P = 0.000). CONCLUSION: CTCs, CEA, CA125 and CA199 were independent risk factors for CRC metastasis.CTCs can be used for the prediction of tumur metastasis, and the evaluation of therapeutic effect.


Asunto(s)
Neoplasias Colorrectales , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Estudios Retrospectivos , Pueblos del Este de Asia , Neoplasias Colorrectales/patología , Antígeno Ca-125 , Biomarcadores de Tumor
5.
Org Biomol Chem ; 21(4): 797-806, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36594562

RESUMEN

Vinylarenes represent an important class of core skeleton embedded in natural products, organic materials, and pharmaceutical molecules. Therefore, numerous efforts have been devoted to developing efficient methods for their preparation. Among them, transition-metal-catalyzed oxidative coupling of arenes and alkenes has proved to be a powerful method due to its high atom and step economy. Although a wide range of oxidative alkenylations of arenes have been developed, the alkenes employed in most cases are still limited to electron-deficient alkenes. Reported herein is a Rh(III)-catalyzed C-H cross-coupling of benzoxazinones and simple unactivated styrenes to furnish a variety of vinylarene scaffolds. This established protocol is characterized by wide functional group compatibility, high yields, and excellent regio- and chemo-selectivity. Mechanistic studies and gram-scale experiments on this high-value conversion are disclosed. Moreover, the potential utility of this method was highlighted by a series of further transformations.

6.
J Med Internet Res ; 25: e43862, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37115595

RESUMEN

BACKGROUND: Mental health problems are a crucial global public health concern. Owing to their cost-effectiveness and accessibility, conversational agent interventions (CAIs) are promising in the field of mental health care. OBJECTIVE: This study aims to present a thorough summary of the traits of CAIs available for a range of mental health problems, find evidence of efficacy, and analyze the statistically significant moderators of efficacy via a meta-analysis of randomized controlled trial. METHODS: Web-based databases (Embase, MEDLINE, PsycINFO, CINAHL, Web of Science, and Cochrane) were systematically searched dated from the establishment of the database to October 30, 2021, and updated to May 1, 2022. Randomized controlled trials comparing CAIs with any other type of control condition in improving depressive symptoms, generalized anxiety symptoms, specific anxiety symptoms, quality of life or well-being, general distress, stress, mental disorder symptoms, psychosomatic disease symptoms, and positive and negative affect were considered eligible. This study followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Data were extracted by 2 independent reviewers, checked by a third reviewer, and pooled using both random effect models and fixed effects models. Hedges g was chosen as the effect size. RESULTS: Of the 6900 identified records, a total of 32 studies were included, involving 6089 participants. CAIs showed statistically significant short-term effects compared with control conditions in improving depressive symptoms (g=0.29, 95% CI 0.20-0.38), generalized anxiety symptoms (g=0.29, 95% CI 0.21-0.36), specific anxiety symptoms (g=0.47, 95% CI 0.07-0.86), quality of life or well-being (g=0.27, 95% CI 0.16-0.39), general distress (g=0.33, 95% CI 0.20-0.45), stress (g=0.24, 95% CI 0.08-0.41), mental disorder symptoms (g=0.36, 95% CI 0.17-0.54), psychosomatic disease symptoms (g=0.62, 95% CI 0.14-1.11), and negative affect (g=0.28, 95% CI 0.05-0.51). However, the long-term effects of CAIs for the most mental health outcomes were not statistically significant (g=-0.04 to 0.39). Personalization and empathic response were 2 critical facilitators of efficacy. The longer duration of interaction with conversational agents was associated with the larger pooled effect sizes. CONCLUSIONS: The findings show that CAIs are research-proven interventions that ought to be implemented more widely in mental health care. CAIs are effective and easily acceptable for those with mental health problems. The clinical application of this novel digital technology will conserve human health resources and optimize the allocation of mental health services. TRIAL REGISTRATION: PROSPERO CRD42022350130; https://tinyurl.com/mvhk6w9p.


Asunto(s)
Salud Mental , Calidad de Vida , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Ansiedad/terapia
7.
J Am Chem Soc ; 144(11): 5126-5135, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35263091

RESUMEN

The reactions of chlorogermylene MsFluindtBu-GeCl 1, supported by a sterically encumbered hydrindacene ligand MsFluindtBu, with NaPCO(dioxane)2.5 and NaAsCO(18-c-6) in the presence of trimethylphosphine afforded trimethylphosphine-stabilized germylidenyl-phosphinidene 2 and -arsinidene 3, respectively. Structural and computational investigations reveal that the Ge-E' bond (E' = P and As) features a multiple-bond character. 2 and 3 exhibit diverse reactivity toward trimethylsilylacetylene and 4-tetrabutylphenylacetylene. Specifically, 2 underwent cycloadditions with both alkynes affording the first six-membered aromatic phosphagermabenzen-1-ylidenes 4 and 5, respectively, through the heavier isocyanide intermediate MsFluindtBu-PGe. In contrast, 3 could serve as a synthetic equivalent of heavier isocyanides and nitriles when treated with trimethylsilylacetylene and 4-tetrabutylphenylacetylene yielding arsagermene 6 and arsolylgermylene 7, respectively. The reaction mechanisms for the cycloadditions were investigated through density functional theory calculations. The reactivity studies highlight the potential of 2 and 3 in accessing heavy main-group element-containing heterocycles.

8.
BMC Psychiatry ; 22(1): 819, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36544175

RESUMEN

BACKGROUND: According to data from the National Health Commission in 2018, more than 30 million children and adolescents in China suffered from mental health problems of varying degrees, with depression accounting for the largest proportion. Life events occur at every stage of child and adolescent development. Many studies have found a relationship between life events and depression in children and adolescents, but few studies have further explored the mediating and moderating variables that influence this relationship. Based on theoretical and empirical research on social support and cognitive styles, this study established a two-stage moderated mediating model to test whether social support mediates life events to depression, and cognitive style moderates the two mediating pathways. METHODS: We recruited 3540 participants from primary and secondary schools in Chongqing and collected 2814 valid data. All the participants completed self-report measures of life events, depression, social support and cognitive styles. The moderated mediation model was examined using SPSS PROCESS model 58. RESULTS: (1) There were significant positive correlations between life events and depression. (2) Social support mediates the relationship between life events and depression in children and adolescents. (3) Cognitive style moderates life events to social support and social support to depression. LIMITATIONS: This is a cross-sectional study and the questionnaire is self-reported. CONCLUSIONS: In children and adolescents, life events can influence depression through the mediating role of social support and cognitive styles could moderate its two mediating pathways.


Asunto(s)
Depresión , Apoyo Social , Humanos , Niño , Adolescente , Depresión/psicología , Estudios Transversales , China , Cognición
9.
J Med Internet Res ; 24(11): e40719, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36355633

RESUMEN

BACKGROUND: Depression has a high prevalence among young adults, especially during the COVID-19 pandemic. However, mental health services remain scarce and underutilized worldwide. Mental health chatbots are a novel digital technology to provide fully automated interventions for depressive symptoms. OBJECTIVE: The purpose of this study was to test the clinical effectiveness and nonclinical performance of a cognitive behavioral therapy (CBT)-based mental health chatbot (XiaoE) for young adults with depressive symptoms during the COVID-19 pandemic. METHODS: In a single-blind, 3-arm randomized controlled trial, participants manifesting depressive symptoms recruited from a Chinese university were randomly assigned to a mental health chatbot (XiaoE; n=49), an e-book (n=49), or a general chatbot (Xiaoai; n=50) group in a ratio of 1:1:1. Participants received a 1-week intervention. The primary outcome was the reduction of depressive symptoms according to the 9-item Patient Health Questionnaire (PHQ-9) at 1 week later (T1) and 1 month later (T2). Both intention-to-treat and per-protocol analyses were conducted under analysis of covariance models adjusting for baseline data. Controlled multiple imputation and δ-based sensitivity analysis were performed for missing data. The secondary outcomes were the level of working alliance measured using the Working Alliance Questionnaire (WAQ), usability measured using the Usability Metric for User Experience-LITE (UMUX-LITE), and acceptability measured using the Acceptability Scale (AS). RESULTS: Participants were on average 18.78 years old, and 37.2% (55/148) were female. The mean baseline PHQ-9 score was 10.02 (SD 3.18; range 2-19). Intention-to-treat analysis revealed lower PHQ-9 scores among participants in the XiaoE group compared with participants in the e-book group and Xiaoai group at both T1 (F2,136=17.011; P<.001; d=0.51) and T2 (F2,136=5.477; P=.005; d=0.31). Better working alliance (WAQ; F2,145=3.407; P=.04) and acceptability (AS; F2,145=4.322; P=.02) were discovered with XiaoE, while no significant difference among arms was found for usability (UMUX-LITE; F2,145=0.968; P=.38). CONCLUSIONS: A CBT-based chatbot is a feasible and engaging digital therapeutic approach that allows easy accessibility and self-guided mental health assistance for young adults with depressive symptoms. A systematic evaluation of nonclinical metrics for a mental health chatbot has been established in this study. In the future, focus on both clinical outcomes and nonclinical metrics is necessary to explore the mechanism by which mental health chatbots work on patients. Further evidence is required to confirm the long-term effectiveness of the mental health chatbot via trails replicated with a longer dose, as well as exploration of its stronger efficacy in comparison with other active controls. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100052532; http://www.chictr.org.cn/showproj.aspx?proj=135744.


Asunto(s)
COVID-19 , Salud Mental , Humanos , Adulto Joven , Femenino , Adolescente , Masculino , Depresión/terapia , Método Simple Ciego , Pandemias
10.
Ecotoxicol Environ Saf ; 241: 113780, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35738100

RESUMEN

Although listed as endocrine disruptor compounds, atrazine (ATZ) is still used in large quantities in agricultural production. Here, alfalfa seedling was cultivated in hydroponic media to investigate the toxic effects of ATZ on alfalfa and accumulation of ATZ in tissues of different plant parts. Alfalfa had a strong upward translocation ability to ATZ. The stress response of alfalfa under ATZ stress was studied using metabolomic and transcriptomic techniques. S-adenosylmethionine, glutathione, 3-mercaptopyruvic acid, ornithine, and aminopropylcadaverine were significantly increased by ATZ in pathways mtr00270 and mtr00480. Several genes of cysteine synthase and spermidine synthase were significantly up-regulated by ATZ induction. They may be markers and genes with potential physiological functions of alfalfa in response to ATZ stress. In addition, using high resolution mass spectrometry, a total of five ATZ metabolites secreted from alfalfa roots were detected. Among them, acetylated deisopropylated ATZ was discovered for the first time. Hydroxylated ATZ and acetylated deethylated ATZ were more readily excreted by the root system. This study not only provides potential genes for the construction of engineering plants to remediate ATZ-contaminated soil, but also provides monitoring objects for the ecological research of ATZ metabolites.


Asunto(s)
Atrazina , Disruptores Endocrinos , Herbicidas , Atrazina/metabolismo , Atrazina/toxicidad , Disruptores Endocrinos/metabolismo , Contaminación Ambiental , Herbicidas/metabolismo , Medicago sativa/metabolismo
11.
Int J Mol Sci ; 23(12)2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35743028

RESUMEN

The 5-methylcytosine (m5C) modification on an mRNA molecule is deposited by Nsun2 and its paralog Nsun6. While the physiological functions of Nsun2 have been carefully studied using gene knockout (KO) mice, the physiological functions of Nsun6 remain elusive. In this study, we generated an Nsun6-KO mouse strain, which exhibited no apparent phenotype in both the development and adult stages as compared to wild-type mice. Taking advantage of this mouse strain, we identified 80 high-confident Nsun6-dependent m5C sites by mRNA bisulfite sequencing in five different tissues and systematically analyzed the transcriptomic phenotypes of Nsun6-KO tissues by mRNA sequencing. Our data indicated that Nsun6 is not required for the homeostasis of these organs under laboratory housing conditions, but its loss may affect immune response in the spleen and oxidoreductive reaction in the liver under certain conditions. Additionally, we further investigated T-cell-dependent B cell activation in KO mice and found that Nsun6 is not essential for the germinal center B cell formation but is associated with the formation of antibody-secreting plasma cells. Finally, we found that Nsun6-mediated m5C modification does not have any evident influence on the stability of Nsun6 target mRNAs, suggesting that Nsun6-KO-induced phenotypes may be associated with other functions of the m5C modification or Nsun6 protein.


Asunto(s)
5-Metilcitosina , 5-Metilcitosina/metabolismo , Animales , Técnicas de Inactivación de Genes , Metilación , Ratones , Ratones Noqueados , ARN Mensajero/genética
12.
Mol Syst Biol ; 16(4): e9367, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32311237

RESUMEN

Alternative polyadenylation (APA) is a major layer of gene regulation. However, it has recently been argued that most APA represents molecular noise. To clarify their functional relevance and evolution, we quantified allele-specific APA patterns in multiple tissues from an F1 hybrid mouse. We found a clearly negative correlation between gene expression and APA diversity for the 2,866 genes (24.9%) with a dominant polyadenylation site (PAS) usage above or equal to 90%, suggesting that their other PASs represent molecular errors. Among the remaining genes with multiple PASs, 3,971 genes (34.5%) express two or more isoforms with potentially functional importance. Interestingly, the genes with potentially functional minor PASs specific to neuronal tissues often express two APA isoforms with distinct subcellular localizations. Furthermore, our analysis of cis-APA divergence shows its pattern across tissues is distinct from that of gene expression. Finally, we demonstrate that the relative usage of alternative PASs is not only affected by their cis-regulatory elements, but also by potential coupling between transcriptional and APA regulation as well as competition kinetics between alternative sites.


Asunto(s)
Perfilación de la Expresión Génica/métodos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Regiones no Traducidas 3' , Alelos , Animales , Línea Celular , Regulación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Ratones , Ratones Endogámicos , Células Madre Embrionarias de Ratones , Poliadenilación , Distribución Tisular
13.
Sensors (Basel) ; 20(18)2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32967134

RESUMEN

Leaf equivalent water thickness (EWT) and dry matter content (expressed as leaf mass per area (LMA)) are two critical traits for vegetation function monitoring, crop yield estimation, and precise agriculture management. Data-driven methods are widely used for remote sensing of leaf EWT and LMA because of their simplicity, satisfactory accuracy, and computation efficiency, such as the vegetation indices (VI)-based and machine learning (ML)-based methods. However, most of the data-driven methods are utilized at the canopy level, comparison of the performances of the data-driven methods at the leaf level has not been well documented. Moreover, the ML-based data-driven methods generally adopt leaf optical properties directly as their inputs, which may subsequently decrease their ability in remote sensing of leaf biochemical constituents. Performances of the ML-based methods cooperating with VI are rarely evaluated. Using the independent LOPEX and ANGERS datasets, we compared the performances of three data-driven methods: VI-based, ML-reflectance-based, and ML-VI-based methods, for the estimation of leaf EWT and LMA. Three sampling strategies were also utilized for evaluation of the generalization of these data-driven methods. Our results evidenced that ML-VI-based methods were the most accurate among these data-driven methods. Compared to the ML-reflectance-based and VI-based methods, the ML-VI-based model with support vector regression overall reduced errors by 5.7% (41.5%) and 1.8% (12.4%) for the estimation of leaf EWT (LMA), respectively. The ML-VI-based model inherits advantages of vegetation indices and ML techniques, which made it sensitive to changes of leaf biochemical constituents and capable of solving nonlinear tasks. It is thus recommended for the estimation of EWT and LMA at the leaf level. Moreover, its performance can further be enhanced by improving its generalization ability, such as adopting techniques on the selection of better wavelengths and definition of new vegetation indices. These results thus provided a prior knowledge of the data-driven methods and can be helpful for future studies on the remote sensing of leaf biochemical constituents.

14.
Phys Rev Lett ; 122(1): 014503, 2019 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-31012644

RESUMEN

We report an experimental measurement of the rms temperature (σ_{T}) profiles in two regions inside a large aspect ratio (Γ=4.2) rectangular convection cell. It is found that, in the region where the boundary layer is sheared by a large-scale wind, σ_{T} has a power-law dependence on the vertical distance (z) from the plate, whereas in the region where plumes are abundant, σ_{T} has a logarithmic dependence on z. The power-law profile may be understood by balancing the inertia force and the viscous force in the equations of motion, and the logarithmic profile may be understood in terms of the balance between the buoyancy and the inertia forces. When normalized by a convective temperature scale, θ_{*}, the profiles of σ_{T} collapse onto a single curve for different values of the Rayleigh number. This shows that the convective temperature first proposed by Deardorff is the suitable temperature scale outside the thermal boundary layer for both logarithmic and power-law profiles. Our finding suggests a strong connection between plumes and the logarithmic rms temperature profile. The present Letter reveals that multiple force balance mechanisms can coexist in the bulk of highly turbulent flows.

15.
Appl Opt ; 56(8): 2195-2200, 2017 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-28375312

RESUMEN

Low timing jitter is a unique merit of superconducting nanowire single-photon detectors (SNSPDs) for time-correlated applications. Quantitative analysis was performed for the SNSPD system. Aided by an oscilloscope with an optimal signal amplitude, we were able to measure a full width at half-maximum system timing jitter as low as 14.2 ps for a high-switching-current SNSPD using a room-temperature low-noise amplifier. When using a time-correlated single-photon counting module, the system timing jitter was 17.3 ps. The detector's intrinsic timing jitter was estimated at ∼12.0 ps.

16.
Opt Express ; 23(11): 14603-11, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26072820

RESUMEN

We demonstrated a laser depth imaging system based on the time-correlated single-photon counting technique, which was incorporated with a low-jitter superconducting nanowire single-photon detector (SNSPD), operated at the wavelength of 1550 nm. A sub-picosecond time-bin width was chosen for photon counting, resulting in a discrete noise of less than one/two counts for each time bin under indoor/outdoor daylight conditions, with a collection time of 50 ms. Because of the low-jitter SNSPD, the target signal histogram was significantly distinguishable, even for a fairly low retro-reflected photon flux. The depth information was determined directly by the highest bin counts, instead of using any data fitting combined with complex algorithms. Millimeter resolution depth imaging of a low-signature object was obtained, and more accurate data than that produced by the traditional Gaussian fitting method was generated. Combined with the intensity of the return photons, three-dimensional reconstruction overlaid with reflectivity data was realized.

17.
Opt Express ; 22(1): 359-68, 2014 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-24514996

RESUMEN

In this paper, the energy-time entangled photon-pairs at 1.5 µm are generated by the spontaneous four wave mixing (SFWM) in optical fibers under continuous wave (CW) pumping. The energy-time entanglement property is demonstrated experimentally through an experiment of Franson-type interference. Although the generation rates of the noise photons are one order of magnitude higher than that of the photon-pairs under CW pumping, the impact of noise photons can be highly suppressed in the measurement by a narrow time domain filter supported by superconducting nanowire single photon detectors with low timing jitters and time correlated single photon counting (TCSPC) module with high time resolution. The experiment results show that the SFWM in optical fibers under CW pumping provides a simple and practical way to generate energy-time entanglement at 1.5 µm, which has great potential for long-distance quantum information applications over optical fibers.

18.
J Med Biochem ; 43(1): 144-152, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38496021

RESUMEN

Background: To analyzes the changes in serum levels of matrix metalloproteinase-9 (MMP-9), neuroenolase (NSE), myeloperoxidase (MPO) and prognostic factors in patients with intracranial aneurysm (IA) undergoing interventional embolization at different treatment times. Methods: A retrospective analysis was made of 200 IA patients admitted to our department from January 2018 to June 2021 was performed. All patients underwent interventional embolization. According to the timing of surgery, the patients were divided into an early group (n=120, onset to surgery ≤72 h) and a delayed group (n=80, onset to surgery >72 h). The effect of embolization, complications and neurological deficit scale (NDS) scores were compared between the two groups. Serum MMP-9, NSE and MPO levels were compared before and after surgery, and the prognosis of all patients within 2 years after surgery was assessed by the Glasgow outcome scale (GOS) and divided accordingly into the good prognosis group (n=147) and the poor prognosis group (n=53) accordingly, and the prognostic factors influencing the patients were analyzed univariately and multifactorially.

19.
Dalton Trans ; 53(5): 2341-2348, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38205856

RESUMEN

Zinc metal is widely considered as the primary option for constructing various aqueous batteries due to its cost-effectiveness, safety, and environmental friendliness. However, the Zn anode continues to be plagued by parasitic reactions and dendrite growth in aqueous electrolytes, limiting the practical implementation of zinc ion batteries (ZIBs) for large-scale energy storage. Herein, a foveolate ZnTe nanoarray is developed as a protective layer to enhance the chemical reversibility during Zn plating/stripping. The semi-conductive ZnTe with excellent ionic conductivity and hydrophobicity can effectually prevent the corrosion reactions, hydrogen generation and dendritic growth on the surface of the Zn anode. As a result, the Zn@ZnTe symmetrical cells achieve ultrahigh cycling stability (over 2800 h at 2 mA cm-2 and 1 mA h cm-2) and simultaneously deliver a low voltage hysteresis of 28 mV. Additionally, the durable Zn@ZnTe//V2O5 cells exhibit a remarkable capacity retention of 96.7% after 3000 cycles, surpassing that of the Zn//V2O5 cells. This work provides a straightforward and low-cost strategy to regulate the interface chemistry of the Zn anode, which may open a way for the development of practical ZIBs.

20.
J Hazard Mater ; 477: 135105, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39047551

RESUMEN

Incense-burning smoke is a deleterious air pollutant that initiates cytotoxic effects by inducing apoptosis in lung epithelial cells and also acts as a risk factor for lung cancers. Auramine, an ingredient of incense smoke, has been implicated in tumor progression and cellular sensitivity in non-small cell lung cancer (NSCLC) towards anti-cancer agents through unclear mechanisms. Tumor protein p53 (TP53)-activated long intergenic non-coding RNA-p21 (lincRNA-p21) undertakes a pivotal role in regulating cell apoptosis and chemosensitivity. TP53 mutations prevalent in 50% of NSCLC, contribute to diminished therapeutic efficacy. However, the influence of auramine on chemotherapy-induced lincRNA-p21 expression and apoptosis in NSCLC with different TP53 genetic statuses remains unexplored. This study disclosed that both wild-type p53 (wtp53) and mutant p53 (mutp53) mediate lincRNA-p21 expression, albeit through distinct promoter enhancers, p53-response element (p53RE) and non-B DNA structure G-quadruplex (GQ), respectively. Intriguingly, auramine functions as an effective stabilizer of the GQ structure, augmenting mutp53-mediated lincRNA-p21 expression and enhancing apoptosis and cellular sensitivity to chemotherapy in mutp53-expressing NSCLC cells. These findings suggest a mechanism by which mutp53, in the presence of auramine, is endowed with tumor-suppressing function akin to wtp53, thereby aiding in combating chemoresistance in NSCLC cells harboring TP53 mutations.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Mutación , ARN Largo no Codificante , Proteína p53 Supresora de Tumor , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Mutación/efectos de los fármacos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Humo/efectos adversos , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacos
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