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1.
Phys Chem Chem Phys ; 26(5): 4455-4465, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38240145

RESUMEN

Storage capacity, average open circuit voltage (OCV), diffusion barrier, lattice parameter changes, etc. are key indicators of whether a material would be suitable for use as a Li-ion or non-Li-ion battery (LIB or NLIB) anode. The rapid development of 2D materials over the past few decades has opened up new possibilities for these metrics. Using first-principles calculations, we prove that two 2D materials, TiB4 and SrB8, show excellent performance in terms of the above metrics when used as anodes for LIBs or NLIBs. As detailed, TiB4 has an Li\Na\K\Ca storage capacity of 588 mA h g-1, 588 mA h g-1, 588 mA h g-1, and 1176 mA h g-1, respectively, and SrB8 has an Li\Na\K\Ca storage capacity of 308 mA h g-1, 308 mA h g-1, 462 mA h g-1, and 616 mA h g-1, respectively, and they show good electrical conductivity whether existing Li, Na, K or Ca is adsorbed or not. The diffusion barriers on both surfaces are low, indicating good rate performance. The average OCV is also very low. In particular, the lattice parameters of the two materials change very little during the embedding of Li\Na\K\Ca. For Ti9B36 the corresponding values are about 0.37% (Li), 0.33% (Na), 0.64% (K) and 0.03% (Ca), and for Sr8B64 the corresponding values are about 0.70% (Li), 0.16% (Na), 0.13% (K) and 0.004% (Ca), which imply zero strain-like character and great cycling performance. All the above results show that TiB4 and SrB8 monolayers are very promising Li\Na\K\Ca ion battery anodes.

2.
Inorg Chem ; 62(28): 11112-11120, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37395531

RESUMEN

Recent decades have witnessed a major development in broadband near-infrared (NIR)-emitting phosphors because of their potential applications in real-time nondestructive examination. These applications require the emission spectra of phosphors to be as broad as possible for efficient performance. Therefore, a blue-light excited LiInF4: Cr3+ phosphor with a NIR emission covering 700-1400 nm is successfully synthesized. Under 470 nm excitation, it shows broadband emission peaked at 980 nm with the full-width at half maximum of 210 nm. The structure and crystal field environment are investigated in detail, and the LiInF4: Cr3+ possesses a weak crystal field strength and strong electron-phonon coupling. An efficient NIR phosphor-converted light-emitting diode (pc-LED) is fabricated by the prepared LiInF4: Cr3+ phosphor and commercial blue diode chip, generating a NIR radiant flux of 5.54 mW at 150 mA drive current. Finally, the NIR pc-LED is successfully applied to identify the blood vessel distribution of the hand. This work suggests the potential of LiInF4: Cr3+ phosphor in applications.

3.
Urban Stud ; 60(9): 1730-1749, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37416835

RESUMEN

The state-society relationship in neighbourhood governance has been a focal topic in the urban governance literature, though the existing scholarship was primarily drawn from non-crisis situations. Adopting a mixed-methods approach, this study investigates the intricate state-society dynamics manifested at the neighbourhood scale as state and societal actors collaborated during China's COVID-19 responses. Our study reveals a pattern of collaborative rather than confrontational dynamics between resident committees and other stakeholders during pandemic responses, which reflects the emergence of a constructed order of neighbourhood co-governance in urban China. Previous community-building reforms consolidated the political legitimacy, power and capacity of resident committees, which were empowered to play a critical coordinating role in bridging hierarchical state mobilisation and horizontal stakeholders in the collaborative pandemic responses. These findings contribute to a more nuanced understanding of neighbourhood co-governance in the international literature and provide lessons for resilience governance from a comparative lens.

4.
Methods Mol Biol ; 2644: 15-33, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37142913

RESUMEN

The MTT assay is extensively used, most often to infer a measure of cytotoxicity of treatments to cells. As with any assay though, there are a number of limitations. The method described here is designed with consideration of how the MTT assay fundamentally works to account for, or at least identify, confounding factors in measurements. It also provides a decision-making framework to best interpret and complement the MTT assay to apply it as either a measure of metabolic activity or cell viability.


Asunto(s)
Proyectos de Investigación , Sales de Tetrazolio/metabolismo , Supervivencia Celular
5.
Small ; 19(35): e2300392, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37127883

RESUMEN

Second near infrared (NIR-II, 1000-1700 nm) fluorescence lifetime imaging is a powerful tool for biosensing, anti-counterfeiting, and multiplex imaging. However, the low photoluminescence quantum yield (PLQY) of fluorescence probes in NIR-II region limits its data collecting efficiency and accuracy, especially in multiplex molecular imaging in vivo. To solve this problem, lanthanide-doped nanoparticles (NPs) ß-NaErF4 : 2%Ce@NaYbF4 @NaYF4 with high PLQY and tunable PL lifetime through multi-ion doping and core-shell structural design, are presented. The obtained internal PLQY can reach up to 50.1% in cyclohexane and 9.2% in water under excitation at 980 nm. Inspired by the above results, a fast NIR-II fluorescence lifetime imaging of whole-body vascular in mice is successfully performed by using the homebuilt fluorescence lifetime imaging system, which reveals a murine abdominal capillary network with low background. A further demonstration of fluorescence lifetime multiplex imaging is carried out in molecular imaging of atherosclerosis cells and different organs in vivo through NPs conjugating with specific peptides and different injection modalities, respectively. These results demonstrate that the high PLQY NPs combined with the homebuilt fluorescence lifetime imaging system can realize a fast and high signal-to-noise fluorescence lifetime imaging; thus, opening a road for multiplex molecular imaging of atherosclerosis.


Asunto(s)
Aterosclerosis , Elementos de la Serie de los Lantanoides , Nanopartículas , Animales , Ratones , Elementos de la Serie de los Lantanoides/química , Espectroscopía Infrarroja Corta/métodos , Imagen Óptica , Nanopartículas/química
6.
Front Public Health ; 11: 1142461, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124799

RESUMEN

Background: The 2019 coronavirus disease (COVID-19) pandemic increased the risks of mental health challenges, especially anxiety and depression. However, the impact of COVID-19 on mental health during pregnancy has not been fully established. Therefore, we investigated the impact of the COVID-19 pandemic on maternal mental health. Methods: Two cohorts of pregnant women at their first antenatal care in the First Affiliated Hospital of Chongqing Medical University were enrolled in this study. One cohort was enrolled before the COVID-19 outbreak, from 1 June to 31 December 2019 (n = 5,728, pre-COVID-19 group), while the other was enrolled during the COVID-19 pandemic, from 24 January to 23 March 2020 (n = 739, COVID-19 pandemic group). Symptoms of depression, anxiety, and somatization disorders were assessed by the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Patient Health Questionnaire-15 (PHQ-15), with a cutoff point of 10 for moderate-to-severe depression, anxiety, and somatoform symptoms. The propensity score matching method (1:1) was used to balance differences in demographic characteristics between groups. A chi-square analysis was performed to compare differences in demographic characteristics between the groups. Results: Prevalence of moderate-to-severe depression, anxiety, and somatoform symptoms among pregnant women at their first antenatal care visit during the COVID-19 pandemic (9.5, 2.2, and 20.8%, respectively) was significantly lower than those before the pandemic (16.3, 4.4, and 25.7%, respectively) (p < 0.05). Compared with the same period before the pandemic, during the pandemic, the number of women newly registered for antenatal care decreased by nearly 50%. There were significant differences in the distributions of demographic characteristics between the groups (p < 0.05). After matching the demographic characteristics, differences in the prevalence of maternal mental health disorders between the groups reversed dramatically. Prevalence of moderate-to-severe depression, anxiety, and somatoform symptoms during the COVID-19 pandemic in this population (2.3, 9.6, and 20.8%, respectively) was significantly higher than those before the pandemic (0.3, 3.9, and 10%, respectively) (p < 0.05). Conclusion: The COVID-19 pandemic increased mental health risks among pregnant women. As a large proportion of pregnant women with mental health challenges delay their prenatal care or change healthcare facilities after the outbreak of public health emergencies, there is a need to establish a balanced healthcare system in medical institutions at all levels.


Asunto(s)
COVID-19 , Mujeres Embarazadas , Femenino , Humanos , Embarazo , Mujeres Embarazadas/psicología , Pandemias , COVID-19/epidemiología , Atención Prenatal , Salud Mental , SARS-CoV-2 , Prevalencia , Puntaje de Propensión , Depresión/epidemiología , Depresión/diagnóstico
7.
Neurosci Lett ; 807: 137259, 2023 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-37075883

RESUMEN

Postoperative cognitive dysfunction (POCD) is common in aged patients after major surgery and is associated with increased risk of long-term morbidity and mortality. However, the underlying mechanism remains largely unknown and the clinical management of POCD is still controversial. Stellate ganglion block (SGB) is a clinical treatment for nerve injuries and circulatory issues. Recent evidence has identified the benefits of SGB in promoting learning and memory. We thus hypothesize that SGB could be effective in improving cognitive function after surgery. In present study, we established POCD model in aged rats via partial liver resection surgery. We found that the development of POCD was associated with the activation of toll-like receptor 4/nuclear factor kapa-B (TLR4/NF-κB) signaling pathway in the microglia in dorsal hippocampus, which induced the production of pro-inflammatory mediators (TNF-α, IL-1ß, IL-6) and promoted neuroinflammation. More importantly, we showed evidence that preoperative treatment with SGB could inhibit microglial activation, suppress TLR4/NF-κB-mediated neuroinflammation and effectively attenuate cognitive decline after the surgery. Our study suggested that SGB may serve as a novel treatment to prevent POCD in elderly patients. As SGB is safe procedure widely used in clinic, our findings can be easily translated into clinical practice and benefit more patients.


Asunto(s)
Disfunción Cognitiva , Complicaciones Cognitivas Postoperatorias , Ratas , Animales , FN-kappa B/metabolismo , Complicaciones Cognitivas Postoperatorias/prevención & control , Complicaciones Cognitivas Postoperatorias/metabolismo , Enfermedades Neuroinflamatorias , Receptor Toll-Like 4/metabolismo , Ganglio Estrellado/metabolismo , Transducción de Señal , Disfunción Cognitiva/etiología , Disfunción Cognitiva/prevención & control , Disfunción Cognitiva/tratamiento farmacológico , Microglía/metabolismo
8.
Animals (Basel) ; 12(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36230250

RESUMEN

Betaine is trimethylglycine and a universal methyl donor which could provide methyl and glycine for cells and animals. As a new star in epigenetics, N6-Methyladenosine has been reported to regulate multiple biological activities, but the regulatory mechanism of betaine on N6-Methyladenosine as well as myogenesis was little studied. In this study, we treated chicken primary myoblast cells with different concentrations of betaine (0, 10, 25, and 50 mmol/L) and found that myoblast cell proliferation was inhibited, although the cell cycle was promoted in the S phase by betaine, where the myotube area was increased as well as the differentiation marker genes MyoD, MyoG, MyHC, Myomarker, and Ckm. RNA sequencing obtained a total of 61 differentially expressed genes (DEGs); DEGs caused by 50 mmol/L betaine were mainly enriched in the regulation of skeletal muscle tissue regeneration and some amino acid metabolic processes. The gene expression pattern trends of all DEGs were mainly clustered into 2 profiles, with the increase in betaine concentration, the gene expression pattern either increased or decreased continuously. Overall, a low concentration betaine can increase the N6-Methyladenosine modification level and myotube area but depresses myoblast cell proliferation in vitro.

9.
J Phys Chem Lett ; 13(2): 718-725, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35025523

RESUMEN

Halide segregation is a critical bottleneck that hampers the application of mixed-halide perovskite nanocrystals (NCs) in both electroluminescent and down-conversion red-light-emitting diodes. Herein, we report a strategy that combines precursor and surface engineering to obtain pure-red-emitting (peaked at 624 nm) NCs with a photoluminescence quantum yield of up to 92% and strongly suppresses the halide segregation of mixed-halide NCs under light irradiation. Red-light-emitting diodes (LED) using these mixed-halide NCs as phosphors exhibit color-stable emission with a negligible peak shift and spectral broadening during operation over 240 min. By contrast, a dramatic peak shift and spectral broadening were observed after 10 min of operation in LEDs based on mixed-halide NCs synthesized by a traditional method. Our strategy is critical to achieving photo- and band-gap-stable mixed-halide perovskite NCs for a variety of optoelectronic applications such as micro-LEDs.

10.
BMC Pregnancy Childbirth ; 21(1): 713, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34702205

RESUMEN

BACKGROUND: Antenatal depression has become a common and serious problem, significantly affecting maternal and fetal health. However, evaluation and intervention methods for pregnant women in obstetric clinics are inadequate. This study aimed to determine the prevalence of and risk factors for depression among all pregnant women at their first attending antenatal care in the obstetrics clinic, a comprehensive teaching hospital, southwest of China. METHODS: From June to December 2019, 5780 pregnant women completed online psychological assessments, and data from 5728 of the women were analyzed. The women were categorized into two groups according to the presence or absence of depression. Depression was assessed by the Patient Health Questionnaire-9 (PHQ-9), with a cutoff point of 10 for depression. Anxiety and somatic symptoms were measured by the Generalized Anxiety Disorder-7 (GAD-7) and Patient Health Questionnaire-15 (PHQ-15), respectively. Univariate analysis and binary logistic regression analysis were used to determine the association among antenatal depression, anxiety, somatic symptoms and participants' characteristics. RESULTS: The prevalence of antenatal depression among all the pregnant women at their first attending antenatal care was 16.3%, higher in the first trimester (18.1%). Anxiety symptoms (Mild anxiety AOR = 2.937; 95% CI: 2.448-3.524) and somatic symptoms (Mild somatic symptoms AOR = 3.938; 95% CI: 2.888-3.368) were major risk factors for antenatal depression among women and the risk increased more with the anxiety level or somatic symptoms level. Gestational weeks (second trimester AOR = 0.611; 95% CI: 0.483-0.773; third trimester AOR = 0.337; 95% CI: 0.228-0.498) and urban residence (AOR = 0.786; 95% CI: 0.652-0.947) were protective factors for antenatal depression among women. CONCLUSIONS: About one in six pregnant women would experience depression, and special attention should be paid to some risk factors (i.e., early pregnancy, anxiety symptoms, somatic symptoms, rural residence). Online psychological assessments might be a time-saving and convenient screening method for pregnant women in obstetric clinics.


Asunto(s)
Depresión/epidemiología , Complicaciones del Embarazo/epidemiología , Mujeres Embarazadas/psicología , Atención Prenatal/psicología , Adulto , China/epidemiología , Estudios Transversales , Femenino , Hospitales de Enseñanza , Humanos , Cuestionario de Salud del Paciente , Embarazo , Prevalencia , Factores de Riesgo
11.
Neurochem Res ; 46(5): 1141-1150, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33534059

RESUMEN

Propofol is one of the most common intravenous anesthetics which may cause neuronal cell death in young mice. HOX transcript antisense RNA (HOTAIR) was abnormally expressed in neurodegenerative diseases. However, the effect of HOTAIR on propofol-induced pyroptosis of neurons and related mechanisms are still unknown. In this study, propofol treatment significantly reduced neuronal the viability of neurons, and promoted the expression of inflammation-related factors. Propofol treatment also promoted neuron death and neuronal pyroptosis. All the above effects might be related to the propofol-induced overexpression of HOTAIR. Interestingly, knockdown of HOTAIR by shRNA (sh-HOTAIR) significantly inhibited neuronal pyroptosis, but increased neuronal viability. Further analysis showed that HOTAIR and Nod-like receptor protein1 (NLRP1) were the targets of miR-455-3p, respectively. Notably, propofol treatment decreased the level of miR-455-3p, while increased the level of NLRP1. In addition, sh-HOTAIR increased the level of miR-455-3p, which further inhibited the expression of NLRP1 and the activation of NLRP1 inflammasome, thereby inhibiting neuronal pyroptosis. More importantly, NLRP1 overexpression decreased neuronal viability, and reactivated NLRP1 inflammasome, thus reversing the inhibitory effect of sh-HOTAIR on pyroptosis. Our findings indicated that HOTAIR inhibited propofol-induced pyroptosis of neurons by regulating miR-455-3p/NLRP1 axis, indicating that HOTAIR may be a potential therapeutic target for propofol-induced neurotoxicity.


Asunto(s)
MicroARNs/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Propofol/farmacología , Piroptosis/fisiología , ARN Largo no Codificante/metabolismo , Animales , Animales Recién Nacidos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Femenino , Técnicas de Silenciamiento del Gen , Hipocampo/citología , Hipocampo/efectos de los fármacos , Masculino , Neuronas/efectos de los fármacos , Piroptosis/efectos de los fármacos , ARN Largo no Codificante/genética , ARN Interferente Pequeño/farmacología , Ratas Sprague-Dawley , Regulación hacia Arriba/efectos de los fármacos
12.
Oncol Rep ; 45(2): 786, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33416180

RESUMEN

Subsequently to the publication of the above paper, the authors have drawn to our attention that, owing to errors made in the compilation of the images in Fig. 6, the images shown in Fig. 6A­C in the article were selected incorrectly (essentially, the images shown in Fig. 6A and B were alterative presentations of the same data shown in Fig. 6C). The authors were able to re­examine the original data files and retrieve the correct data panels. The revised version of Fig. 6, featuring the corrected data panels for Fig. 6A­C, is shown opposite. Note that the revisions made to this figure do not affect the overall conclusions reported in the paper. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish this Corrigendum, and apologize to the readership for any inconvenience caused. [the original article was published in Oncology Reports 36: 2017-2024, 2016; DOI: 10.3892/or.2016.4995].

13.
Exp Mol Pathol ; 115: 104444, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32335082

RESUMEN

Intestinal ischemia-reperfusion (I/R) is a life-threatening condition associated with high morbidity and mortality. Dexmedetomidine (DEX), an agonist of α2-adrenoceptor with sedation and analgesia effect, has recently been identified with protective function against I/R injury in multiple organs. However, the mechanism underlying the beneficial effect of DEX on intestine after I/R injury remained poorly understood. In the present study, using in both in vitro and in vivo models, we found that intestinal I/R injury was associated with the activation of p38 MAPK cascade, while DEX was capable of deactivating p38 MAPK and thus protect intestinal cells from apoptosis by inhibiting p38 MAPK-mediated mitochondrial depolarization and cytochrome c (Cyto C) release. Moreover, through inhibiting p38 MAPK activity, the downstream production of pro-inflammatory cytokines-regulated by NF-κB was also suppressed by DEX treatment, leading to the resolution of I/R-induced inflammation in intestine. In general, our study provided evidence that DEX protected intestine from I/R injury by inhibiting p38 MAPK-mediated mitochondrial apoptosis and inflammatory response.


Asunto(s)
Dexmedetomidina/uso terapéutico , Intestinos/patología , Sistema de Señalización de MAP Quinasas , Sustancias Protectoras/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/enzimología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Células CACO-2 , Dexmedetomidina/farmacología , Glucosa/deficiencia , Humanos , Inflamación/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , FN-kappa B/metabolismo , Oxígeno , Sustancias Protectoras/farmacología , Ratas Wistar , Daño por Reperfusión/patología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
14.
Inorg Chem ; 58(9): 6376-6387, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31012577

RESUMEN

Cation-substitution-induced controllable luminescence tuning could efficiently optimize and improve the luminescence performances of novel phosphor materials for realizing high-quality lighting. As important members of the orthophosphate family, ABPO4 (A = alkali metal Li, Na, K, Rb, Cs; B = alkali earth metal Mg, Ca, Sr, Ba) offers an abundant cation lattice environment for rare earth ions. Herein, we successfully prepared a broad-band red-emitting CsMgPO4:Eu2+ phosphor with an emission peak at 628 nm (fwhm = 118 nm). A series of cation-substitution strategies are designed to adjust and enhance its luminescence performances. The corresponding mechanisms are also investigated and proposed reasonably. A charge-compensation strategy of [Eu2+-Si4+] → [Cs+-P5+] could dramatically enhance the quenching concentration from 0.04 to 0.30, which is attributed to the decrease of Eu3+. Two cation-substitution strategies of larger Ba2+ (Sr2+) ions for Mg2+ ions could achieve superior emission adjustment of Eu2+ ions from the red to blue (yellow) region due to local lattice distortion. Interestingly, a consecutive emission adjustment from the red to blue region by simply changing the annealed temperature is reported for the first time, and the possible emission tuning mechanism is revealed based on a local lattice-strain control. This study could serve as a guide in developing Eu2+-activated ABPO4 phosphors with improving luminescence performance and controllable luminescence adjustment based on charge compensation and lattice-strain control through various cation substitutions.

15.
Light Sci Appl ; 8: 15, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30728955

RESUMEN

Phosphor-converted white-light-emitting diodes (pc-WLED) have been extensively employed as solid-state lighting sources, which have a very important role in people's daily lives. However, due to the scarcity of the red component, it is difficult to realize warm white light efficiently. Hence, red-emitting phosphors are urgently required for improving the illumination quality. In this work, we develop a novel orangish-red La4GeO8:Bi3+ phosphor, the emission peak of which is located at 600 nm under near-ultraviolet (n-UV) light excitation. The full width at half maximum (fwhm) is 103 nm, the internal quantum efficiency (IQE) exceeds 88%, and the external quantum efficiency (EQE) is 69%. According to Rietveld refinement analysis and density functional theory (DFT) calculations, Bi3+ ions randomly occupy all La sites in orthorhombic La4GeO8. Importantly, the oxygen-vacancy-induced electronic localization around the Bi3+ ions is the main reason for the highly efficient orangish-red luminescence. These results provide a new perspective and insight from the local electron structure for designing inorganic phosphor materials that realize the unique luminescence performance of Bi3+ ions.

16.
Adv Mater ; 31(16): e1807592, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30803066

RESUMEN

Lead halide perovskites (LHPs) have received increased attention owing to their intriguing optoelectronic and photonic properties. However, the toxicity of lead and the lack of long-term stability are potential obstacles for the application of LHPs. Herein, the epitaxial synthesis of CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) by surface chemical conversion of Cs2 GeF6 double perovskites with PbX2 (X = Cl, Br, I) is reported. The experimental results show that the surface of the Cs2 GeF6 double perovskites is partially converted into CsPbX3 perovskite QDs and forms a CsPbX3 /Cs2 GeF6 hybrid structure. The theoretical calculations reveal that the CsPbBr3 conversion proceeds at the Cs2 GeF6 edge through sequential growth of multiple PbBr6 4- layers. Through the conversion strategy, luminescent and color-tunable CsPbX3 QDs can be obtained, and these products present high stability against decomposition due to anchoring effects. Moreover, by partially converting red emissive Cs2 GeF6 :Mn4+ to green emissive CsPbBr3 , the CsPbBr3 /Cs2 GeF6 :Mn4+ hybrid can be employed as a low-lead hybrid perovskite phosphor on blue LED chips to produce white light. The leadless CsPbX3 /Cs2 GeF6 hybrid structure with stable photoluminescence opens new paths for the rational design of efficient emission phosphors and may stimulate the design of other functional CsPbX3 /Cs-containing hybrid structures.

17.
Artículo en Inglés | MEDLINE | ID: mdl-30629500

RESUMEN

Learning similarity of two images is an important problem in computer vision and has many potential applications. Most of previous works focus on generating image similarities in three aspects: global feature distance computing, local feature matching and image concepts comparison. However, the task of directly detecting class agnostic common objects from two images has not been studied before, which goes one step further to capture image similarities at region level. In this paper, we propose an end-to-end Image Common Object Detection Network (CODN) to detect class agnostic common objects from two images. The proposed method consists of two main modules: locating module and matching module. The locating module generates candidate proposals of each two images. The matching module learns the similarities of the candidate proposal pairs from two images, and refines the bounding boxes of the candidate proposals. The learning procedure of CODN is implemented in an integrated way and a multi-task loss is designed to guarantee both region localization and common object matching. Experiments are conducted on PASCAL VOC 2007 and COCO 2014 datasets. Experimental results validate the effectiveness of the proposed method.

18.
Mikrochim Acta ; 185(11): 519, 2018 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-30361934

RESUMEN

CdTe quantum dots (QDs) were integrated with polyethyleneimine-coated carbon dots (PEI-CDs) to form a dually emitting probe for heparin. The red fluorescence of the CdTe QDs is quenched by the PEI-CDs due to electrostatic interactions. In the presence of heparin, the blue fluorescence of PEI-CDs remains unaffected, while its quenching effect on the fluorescence of CdTe QDs is strongly reduced. A ratiometric fluorometric assay was worked out. The ratio of the fluorescences at 595 and 436 nm serves as the analytical signal. Response is linear in the concentration range of 50-600 ng·mL-1 (0.1-1.2 U·mL-1) of heparin. The limit of detection is 20 ng·mL-1 (0.04 U·mL-1). This makes the method a valuable tool for heparin monitoring during postoperative and long-term care. This assay is relatively free from the interference by other analogues which commonly co-exist with heparin in samples, and it is more robust than single-wavelength based assays. Graphical abstract In the presence of heparin, the fluorescence of polyethyleneimine-coated carbon dots (PEI-CDs) at 436 nm remains unaffected, while its quenching effect on the fluorescence of CdTe at 595 nm is strongly reduced.


Asunto(s)
Compuestos de Cadmio/química , Carbono/química , Fluorometría/métodos , Heparina/análisis , Polietileneimina/química , Puntos Cuánticos/química , Telurio/química , Heparina/sangre , Humanos , Concentración de Iones de Hidrógeno , Factores de Tiempo
19.
Inorg Chem ; 57(15): 9251-9259, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-29995392

RESUMEN

In the pursuit of high-quality W-LED lighting, the precise control of emission color of phosphor materials is indispensable. Herein we report a series of single-composition Bi3+-doped LiCa3MgV3O12 garnet-structure phosphors, whose emission colors under n-UV excitation could be tuned from bluish green (480 nm) to yellow (562 nm) on the basis of local lattice distortion and VO43- → Bi3+ energy transfer. Furthermore, full-color luminescence tuning from bluish green to orangish red across the warm white light region was successfully achieved by designing VO43- → Bi3+ → Eu3+ energy transfers. More interestingly, the thermal stabilities of as-prepared samples were gradually enhanced through designing VO43-/Bi3+ → Eu3+ energy transfers. This work provides a new perspective for color tuning originating from simultaneous local lattice distortion and multiple energy transfers.

20.
J Vet Med Sci ; 80(5): 829-835, 2018 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-29553069

RESUMEN

Bacteria of the genus Providencia are opportunistic pathogens of clinical significance due to their association with diarrhea and urinary tract infections. The present study was conducted to examine the prevalence and antimicrobial resistance of Providencia spp. in retail meats sold in Guangzhou, China and Osaka, Japan. Out of 158 meat samples including beef, pork and chicken, 67 Providencia (42%) belonging to four species viz., P. alcalifaciens, P. rustigianii, P. stuartii and P. rettgeri were isolated, and most of them were resistant to tetracycline (91%) followed by ampicillin (69%) and streptomycin (49%). Of 67 isolates, 29 (43%) were MDR, which is defined to be resistant to more than three classes of antimicrobials. No statistically significant differences were observed between Chinese and Japanese retail meat samples regarding contamination rate of Providencia spp. as well as frequency of the antimicrobial resistance of the isolates including MDR. Class 1 and/or class 2 integrons were detected in six of the eight isolates that were resistant to more than 4 antimicrobials, however none of the isolates harbored class 3 integron. A P. rustigianii harboring the blaOXA-10 gene was isolated, which is the first report of Providencia with blaOXA-10 gene of food origin. These data suggest that retail meats in China and Japan are substantially contaminated with Providencia spp., which displayed a high frequency of antimicrobial resistance, and establishing the surveillance of Providencia spp., especially antimicrobial resistant one, in retail meats is imperative.


Asunto(s)
Pollos/microbiología , Microbiología de Alimentos , Integrones , Carne/microbiología , Providencia/aislamiento & purificación , Carne Roja/microbiología , Animales , Antibacterianos/farmacología , Bovinos , China , Farmacorresistencia Bacteriana Múltiple/genética , Productos Pesqueros/microbiología , Pruebas de Sensibilidad Microbiana , Prevalencia , Providencia/efectos de los fármacos , Providencia/genética
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