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1.
Opt Lett ; 49(20): 5735-5738, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39404525

RESUMEN

We study multiplexed quantum frequency conversion (m-QFC) on a single waveguide, where a single pump beam simultaneously converts multiple signal beams at distinct wavelengths. Using a three-peak periodically poled lithium niobate (PPLN) waveguide, we demonstrate the multiplexed upconversion in the telecom band with internal efficiencies up to 73.6%. Tested with a multichannel photon-pair source, the quantum correlation is preserved well after the conversion, with coincidence-to-accidental ratio reaching 767. These results highlight a viable device approach to multiplexed quantum key distribution, quantum sensing, and quantum computing.

2.
Opt Lett ; 49(12): 3388-3391, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875627

RESUMEN

We demonstrate an invertible all-optical gate on chip, with the roles of control and signal switchable by slightly adjusting their relative arrival time at the gate. It is based on the quantum Zeno blockade (QZB) driven by sum-frequency generation (SFG) in a periodically poled lithium niobate microring resonator. For two nearly identical nanosecond pulses, the later arriving pulse is modulated by the earlier arriving one, resulting in 2.4 and 3.9 power extinction between the two, respectively, when their peak powers are 1 mW and 2 mW, respectively. Our results, while to be improved and enriched, herald a new, to the best of our knowledge, paradigm of logical gates and circuits for exotic applications.

3.
Opt Lett ; 49(9): 2449-2452, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691741

RESUMEN

Broadband frequency comb generation through cascaded quadratic nonlinearity remains experimentally untapped in free-space cavities with bulk χ(2) materials mainly due to the high threshold power and restricted ability of dispersion engineering. Thin-film lithium niobate (LN) is a good platform for nonlinear optics due to the tight mode confinement in a nano-dimensional waveguide, the ease of dispersion engineering, large quadratic nonlinearities, and flexible phase matching via periodic poling. Here we demonstrate broadband frequency comb generation through dispersion engineering in a thin-film LN microresonator. Bandwidths of 150 nm (80 nm) and 25 nm (12 nm) for center wavelengths at 1560 and 780 nm are achieved, respectively, in a cavity-enhanced second-harmonic generation (doubly resonant optical parametric oscillator). Our demonstration paves the way for pure quadratic soliton generation, which is a great complement to dissipative Kerr soliton frequency combs for extended interesting nonlinear applications.

4.
J Org Chem ; 89(14): 10112-10126, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38959135

RESUMEN

A photoredox-promoted decarboxylative C-H glycosylation for the synthesis of nonclassical heteroaryl C-glycosides is reported. This methodology is characterized by an exceedingly simple reaction system, high diastereoselectivity, and good functional group tolerance. Moreover, the operational procedure is simple, and the gram-scale reaction highlights the practical applicability of this protocol.

5.
Org Biomol Chem ; 22(29): 6016-6021, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39007287

RESUMEN

Simple and practical strategies for visible-light-induced C-H alkylation of 2-amino-1,4-naphthoquinones with cyclobutanone oxime esters and hydroxamic acid derivatives have been developed under mild and redox-neutral conditions. These two reactions can be carried out at room temperature and obtain a variety of 2-amino-1,4-naphthoquinone derivatives with cyano and amide groups. Moreover, the cyanoalkylation reaction of 2-amino-1,4-naphthoquinones can proceed smoothly in the absence of photocatalysts.

6.
Neurol Sci ; 45(6): 2719-2728, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38150131

RESUMEN

OBJECTIVES: Patients with severe stroke are at high risk of developing acute respiratory distress syndrome (ARDS), but this severe complication was often under-diagnosed and rarely explored in stroke patients. We aimed to investigate the prevalence, early predictors, and outcomes of ARDS in severe stroke. METHODS: This prospective study included consecutive patients admitted to neurological intensive care unit (neuro-ICU) with severe stroke, including acute ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The incidence of ARDS was examined, and baseline characteristics and severity scores on admission were investigated as potential early predictors for ARDS. The in-hospital mortality, length of neuro-ICU stay, the total cost in neuro-ICU, and neurological functions at 90 days were explored. RESULTS: Of 140 patients included, 35 (25.0%) developed ARDS. Over 90% of ARDS cases occurred within 1 week of admission. Procalcitonin (OR 1.310 95% CI 1.005-1.707, P = 0.046) and PaO2/FiO2 on admission (OR 0.986, 95% CI 0.979-0.993, P < 0.001) were independently associated with ARDS, and high brain natriuretic peptide (OR 0.994, 95% CI 0.989-0.998, P = 0.003) was a red flag biomarker warning that the respiratory symptoms may be caused by cardiac failure rather than ARDS. ARDS patients had longer stays and higher expenses in neuro-ICU. Among patients with ARDS, 25 (62.5%) were moderate or severe ARDS. All the patients with moderate to severe ARDS had an unfavorable outcome at 90 days. CONCLUSIONS: ARDS is common in patients with severe stroke, with most cases occurring in the first week of admission. Procalcitonin and PaO2/FiO2 on admission are early predictors of ARDS. ARDS worsens both short-term and long-term outcomes. The conflict in respiratory support strategies between ARDS and severe stroke needs to be further studied.


Asunto(s)
Síndrome de Dificultad Respiratoria , Accidente Cerebrovascular , Humanos , Síndrome de Dificultad Respiratoria/epidemiología , Síndrome de Dificultad Respiratoria/complicaciones , Masculino , Femenino , Anciano , Estudios Prospectivos , Prevalencia , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/complicaciones , Unidades de Cuidados Intensivos/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Mortalidad Hospitalaria , Anciano de 80 o más Años , Tiempo de Internación/estadística & datos numéricos
7.
J Sci Food Agric ; 104(3): 1824-1832, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37884460

RESUMEN

BACKGROUND: Rice taste is closely associated with endosperm composition, which varies among different rice layers. Although clarifying the relationship between this difference and nutritional taste can guide rice breeding and cultivation practices, research on this topic is limited. RESULTS: Here, typical rice varieties having excellent and poor taste characteristics were selected to analyze the distribution characteristics and differences of their components. The varieties with excellent taste exhibited lower apparent amylose content (AAC) and protein content (PC), lesser short-chain (Fa) and long-chain (Fb3 ) amylopectin (AP) and more medium-chain (Fb1+2 ) AP, higher long-to-short chain ratio (Fa:Fb3 ), and higher nitrogen (N), magnesium (Mg) and calcium (Ca) content in layer 1 (L1) than the varieties with poor taste. Layer 2 (L2) played a key role in AAC and PC regulation in the varieties with excellent taste by reducing AAC and appropriately increasing PC, consequently improving rice taste. AP structure in layer 3 (L3) substantially affected the taste of the two types of varieties. The mineral content was the highest in L1, and increased potassium (K), Ca, and Mg content improved taste in all varieties. CONCLUSION: AAC in each layer contributes to rice taste. PC and minerals primarily act on L1 and L2, whereas AP acts on L2 and L3. Therefore, the endosperm formation process should be exploited for improving rice taste. Furthermore, key resources and cultivation should be identified and regulated, respectively, to improve rice taste. © 2023 Society of Chemical Industry.


Asunto(s)
Oryza , Oryza/química , Gusto , Fitomejoramiento , Amilopectina/química , Endospermo/química , Amilosa/análisis , Minerales/análisis , Magnesio/análisis , Almidón/química
8.
Epilepsia ; 64(6): 1594-1604, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36892496

RESUMEN

OBJECTIVE: This study was undertaken to characterize the blood-brain barrier (BBB) dysfunction in patients with new onset refractory status epilepticus (NORSE) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: This study included three groups of adult participants: patients with NORSE, encephalitis patients without status epilepticus (SE), and healthy subjects. These participants were retrospectively included from a prospective DCE-MRI database of neurocritically ill patients and healthy subjects. The BBB permeability (Ktrans) in the hippocampus, basal ganglia, thalamus, claustrum, periventricular white matter, and cerebellum were measured and compared between these three groups. RESULTS: A total of seven patients with NORSE, 14 encephalitis patients without SE, and nine healthy subjects were included in this study. Among seven patients with NORSE, only one had a definite etiology (autoimmune encephalitis), and the rest were cryptogenic. Etiology of encephalitis patients without SE included viral (n = 2), bacterial (n = 8), tuberculous (n = 1), cryptococcal (n = 1), and cryptic (n = 2) encephalitis. Of these 14 encephalitis patients without SE, three patients had seizures. Compared to healthy controls, NORSE patients had significantly increased Ktrans values in the hippocampus (.73 vs. .02 × 10-3 /min, p = .001) and basal ganglia (.61 vs. .003 × 10-3 /min, p = .007) and a trend in the thalamus (.24 vs. .08 × 10-3 /min, p = .017). Compared to encephalitis patients without SE, NORSE patients had significantly increased Ktrans values in the thalamus (.24 vs. .01 × 10-3 /min, p = .002) and basal ganglia (.61 vs. .004 × 10-3 /min, p = .013). SIGNIFICANCE: This exploratory study demonstrates that BBBs of NORSE patients were impaired diffusely, and BBB dysfunction in the basal ganglia and thalamus plays an important role in the pathophysiology of NORSE.


Asunto(s)
Encefalitis , Estado Epiléptico , Adulto , Humanos , Barrera Hematoencefálica/diagnóstico por imagen , Estudios Retrospectivos , Estudios Prospectivos , Estado Epiléptico/diagnóstico por imagen , Estado Epiléptico/etiología , Encefalitis/complicaciones , Imagen por Resonancia Magnética
9.
Bull Environ Contam Toxicol ; 109(5): 808-816, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36056950

RESUMEN

Heavy metals pollution in pharmaceutical industries received increasing attention. A total of 94 soil samples were collected in this study. Results showed the mean contents of Hg, Cd, As, Pb, Ni and Cu were 0.21, 0.26, 9.59, 55.06, 51.52 and 50.81 mg·kg-1, respectively. The spatial distribution of metals in topsoil largely attributed to the pharmaceutical production process. The distribution of Hg and As were related to the production of medical absorbent cotton. While Ni was related to the fuel supply of Ni-rich coal. Cr, Cu and Pb mainly distributed in the process which they were used as catalysts. The vertical migration of metals was complex in soil. To a great extent, it was related to the texture of the soil and the properties of metals in this filed. The total non-cancer and cancer human health risk were within the limits of USEPA (10-6 a-1). This demonstrated the health risks of individual's exposure to heavy metals in this factory was acceptable.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes del Suelo , Humanos , Contaminantes del Suelo/análisis , Plomo , Monitoreo del Ambiente/métodos , Medición de Riesgo , Metales Pesados/análisis , Suelo , Preparaciones Farmacéuticas , China
10.
Opt Lett ; 45(13): 3789-3792, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32630955

RESUMEN

Thin-film lithium-niobate-on-insulator (LNOI) has emerged as a superior integrated-photonics platform for linear, nonlinear, and electro-optics. Here we combine quasi-phase-matching, dispersion engineering, and tight mode confinement to realize nonlinear parametric processes with both high efficiency and wide wavelength tunability. On a millimeter-long, Z-cut LNOI waveguide, we demonstrate efficient (1900±500%W-1cm-2) and highly tunable (-1.71nm/K) second-harmonic generation from 1530 to 1583 nm by type-0 quasi-phase-matching. Our technique is applicable to optical harmonic generation, quantum light sources, frequency conversion, and many other photonic information processes across visible to mid-IR spectral bands.

11.
Phys Rev Lett ; 125(26): 263602, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33449782

RESUMEN

Quantum photon sources of high rate, brightness, and purity are increasingly desirable as quantum information systems are quickly scaled up and applied to many fields. Using a periodically poled lithium niobate microresonator on chip, we demonstrate photon-pair generation at high rates of 8.5 and 36.3 MHz using only 3.4 and 13.4 µW pump power, respectively, marking orders of magnitude improvement over the state of the art, across all material platforms. These results constitute the first direct measurement of the device's giant single photon nonlinearity. The measured coincidence to accidental ratio is well above 100 at those high rates and reaches 14682±4427 at a lower pump power. The same chip enables heralded single-photon generation at tens of megahertz rates, each with low autocorrelation g_{H}^{(2)}(0)=0.008 and 0.097 for the microwatt pumps, which marks a new milestone. Such distinct performance, facilitated by the chip device's noiseless and giant optical nonlinearity, will contribute to the forthcoming pervasive adoption of quantum optical information technologies.

12.
Proc Natl Acad Sci U S A ; 114(24): 6197-6202, 2017 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-28566497

RESUMEN

Leveraging the most recent success in expanding the electrochemical stability window of aqueous electrolytes, in this work we create a unique Li-ion/sulfur chemistry of both high energy density and safety. We show that in the superconcentrated aqueous electrolyte, lithiation of sulfur experiences phase change from a high-order polysulfide to low-order polysulfides through solid-liquid two-phase reaction pathway, where the liquid polysulfide phase in the sulfide electrode is thermodynamically phase-separated from the superconcentrated aqueous electrolyte. The sulfur with solid-liquid two-phase exhibits a reversible capacity of 1,327 mAh/(g of S), along with fast reaction kinetics and negligible polysulfide dissolution. By coupling a sulfur anode with different Li-ion cathode materials, the aqueous Li-ion/sulfur full cell delivers record-high energy densities up to 200 Wh/(kg of total electrode mass) for >1,000 cycles at ∼100% coulombic efficiency. These performances already approach that of commercial lithium-ion batteries (LIBs) using a nonaqueous electrolyte, along with intrinsic safety not possessed by the latter. The excellent performance of this aqueous battery chemistry significantly promotes the practical possibility of aqueous LIBs in large-format applications.

13.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(6): 643-650, 2020 Jun.
Artículo en Zh | MEDLINE | ID: mdl-32571466

RESUMEN

OBJECTIVE: To study the association between maternal alcohol consumption and the risk of congenital heart disease (CHD) in offspring. METHODS: PubMed, Cochrane Library, Web of Science, Google Scholar, China Biology Medicine disc, Wanfang Database, CNKI Database, and Weipu Database were searched for the articles on the association between maternal alcohol consumption and congenital heart disease in offspring. These articles were published up to November 30, 2019. A random effects model or a fixed effects model was used for the pooled analysis of the results of each study, and then the pooled effective value and its 95%CI were calculated. A subgroup analysis was performed to explore heterogeneous regulators. Funnel plots and an Egger's test were used to assess publication bias. RESULTS: A total of 4 409 articles were searched, and 55 articles were finally included in this analysis, among which there were 6 cohort studies and 49 case-control studies. The Meta analysis showed heterogeneity across all studies (I2=74%, P<0.01). The random effects model showed that maternal alcohol consumption was associated with CHD in offspring, with an OR of 1.18 (95%CI: 1.09-1.28). The Egger's test showed a certain degree of publication bias (P<0.05), and after adjustment, the pooled OR of CHD in offspring was 1.10 (95%CI: 1.01-1.21). CONCLUSIONS: Maternal alcohol consumption may increase the risk of CHD in offspring.


Asunto(s)
Consumo de Bebidas Alcohólicas , Cardiopatías Congénitas , Estudios de Casos y Controles , China , Estudios de Cohortes , Humanos , Factores de Riesgo
14.
J Am Chem Soc ; 139(29): 9775-9778, 2017 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-28704997

RESUMEN

Rechargeable aqueous Zn/MnO2 battery chemistry in a neutral or mildly acidic electrolyte has attracted extensive attention recently because all the components (anode, cathode, and electrolyte) in a Zn/MnO2 battery are safe, abundant, and sustainable. However, the reaction mechanism of the MnO2 cathode remains a topic of discussion. Herein, we design a highly reversible aqueous Zn/MnO2 battery where the binder-free MnO2 cathode was fabricated by in situ electrodeposition of MnO2 on carbon fiber paper in mild acidic ZnSO4+MnSO4 electrolyte. Electrochemical and structural analysis identify that the MnO2 cathode experience a consequent H+ and Zn2+ insertion/extraction process with high reversibility and cycling stability. To our best knowledge, it is the first report on rechargeable aqueous batteries with a consequent ion-insertion reaction mechanism.

15.
Nano Lett ; 16(7): 4521-7, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27322663

RESUMEN

All-solid-state lithium-sulfur batteries (ASSLSBs) using highly conductive sulfide-based solid electrolytes suffer from low sulfur utilization, poor cycle life, and low rate performance due to the huge volume change of the electrode and the poor electronic and ionic conductivities of S and Li2S. The most promising approach to mitigate these challenges lies in the fabrication of a sulfur nanocomposite electrode consisting of a homogeneous distribution of nanosized active material, solid electrolyte, and carbon. Here, we reported a novel bottom-up method to synthesize such a nanocomposite by dissolving Li2S as the active material, polyvinylpyrrolidone (PVP) as the carbon precursor, and Li6PS5Cl as the solid electrolyte in ethanol, followed by a coprecipitation and high-temperature carbonization process. Li2S active material and Li6PS5Cl solid electrolyte with a particle size of ∼4 nm were uniformly confined in a nanoscale carbon matrix. The homogeneous nanocomposite electrode consisting of different nanoparticles with distinct properties of lithium storage capability, mechanical reinforcement, and ionic and electronic conductivities enabled a mechanical robust and mixed conductive (ionic and electronic conductive) sulfur electrode for ASSLSB. A large reversible capacity of 830 mAh/g (71% utilization of Li2S) at 50 mA/g for 60 cycles with a high rate performance was achieved at room temperature even at a high loading of Li2S (∼3.6 mg/cm(2)). This work provides a new strategy to design a mechanically robust, mixed conductive nanocomposite electrode for high-performance all-solid-state lithium sulfur batteries.

16.
J Stroke Cerebrovasc Dis ; 26(1): e1-e4, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28341077

RESUMEN

OBJECTIVE: To explore Notch3 mutation sites of Chinese patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). METHODS: Direct sequencing of all exons in Notch3 gene was performed on 12 unrelated suspected CADASIL cases from mainland China. RESULT: A missense p.Arg587Cys (1759C>T) mutation in exon 11 was identified in 2 patients through genetic analysis. CONCLUSION: Chinese patients with CADASIL of R587C mutation in exon 11 was firstly reported.


Asunto(s)
CADASIL/genética , Mutación Missense , Receptor Notch3/genética , Pueblo Asiatico/genética , Encéfalo/diagnóstico por imagen , CADASIL/diagnóstico por imagen , China , Exones , Familia , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Angew Chem Int Ed Engl ; 56(43): 13526-13530, 2017 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-28849616

RESUMEN

The redox chemistry of magnesium and its application in rechargeable Mg batteries has received increasing attention owing to the unique benefits of Mg metal electrodes, namely high reversibility without dendrite formation, low reduction potentials, and high specific capacities. The Mg/S couple is of particular interest owing to its high energy density and low cost. Previous reports have confirmed the feasibility of a rechargeable Mg/S battery; however, only limited cycling stability was achieved, and the complicated procedure for the preparation of the electrolytes has significantly compromised the benefits of Mg/S chemistry and hindered the development of Mg/S batteries. Herein, we report the development of the first rechargeable Mg/S battery with a MgTFSI2 /MgCl2 /DME electrolyte (DME=1,2-dimethoxyethane, TFSI=bis(trifluoromethanesulfonyl)imide) and realize the best cycling stability among all reported Mg/S batteries by suppressing polysulfide dissolution. Mechanistic studies show that the battery works via S0 /MgSx redox processes and that the large voltage hysteresis is mainly due to the Mg anode overpotential.

18.
Angew Chem Int Ed Engl ; 55(25): 7136-41, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27120336

RESUMEN

A new super-concentrated aqueous electrolyte is proposed by introducing a second lithium salt. The resultant ultra-high concentration of 28 m led to more effective formation of a protective interphase on the anode along with further suppression of water activities at both anode and cathode surfaces. The improved electrochemical stability allows the use of TiO2 as the anode material, and a 2.5 V aqueous Li-ion cell based on LiMn2 O4 and carbon-coated TiO2 delivered the unprecedented energy density of 100 Wh kg(-1) for rechargeable aqueous Li-ion cells, along with excellent cycling stability and high coulombic efficiency. It has been demonstrated that the introduction of a second salts into the "water-in-salt" electrolyte further pushed the energy densities of aqueous Li-ion cells closer to those of the state-of-the-art Li-ion batteries.

19.
J Environ Sci (China) ; 26(3): 593-600, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25079272

RESUMEN

Organochlorine pesticide (OCP) concentrations in tree bark from the upper Yellow River region were determined. Total OCP concentrations ranged from 2.7 to 82 ng/g dw, with a mean of 20 ng/g dw. Concentrations of total (Σ) DDTs (0.49-37 ng/g dw), HCHs (0.55-4.5 ng/g dw), and HCB (0.1-1.0 ng/g dw) were much higher than the other OCPs and accounted for 89% of the ΣOCP concentrations. p,p'-DDT was the dominant member of the DDT pesticide group and ß-HCH was the dominant HCH isomer. The p,p'-DDT/p,p'-DDE and α-HCH/γ-HCH ratios suggested that there were recent DDT and γ-HCH releases. OCP concentrations in the air were estimated from the tree bark, and the estimated median ΣDDTs, ΣHCHs, and HCB concentrations in the air were 0.09, 0.14, and 0.024 pg/m(3), respectively. The relationship between total OCP concentrations and socioeconomic and natural environment indices were assessed using multiple linear regression analysis, and a regression equation including all these factors was obtained. Population density and tertiary industry were the two dominant factors that appeared to affect OCP concentrations in the upper Yellow River region.


Asunto(s)
Contaminantes Atmosféricos/análisis , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Corteza de la Planta/química , China , Ambiente , Análisis de Regresión , Factores Socioeconómicos
20.
Chem Commun (Camb) ; 60(45): 5860-5863, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38753015

RESUMEN

A photoredox promoted decarboxylative C-H glycosylation has been developed for the synthesis of heteroaryl C-glycosides. This methodology is characterized by its exceedingly simple reaction system, high diastereoselectivity and good functional group tolerance. Moreover, this innovative approach circumvents the need for high temperatures, transition metals, and photocatalysts, providing an environmentally friendly, straightforward, and efficient protocol.

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