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1.
Soc Sci Med ; 356: 117141, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39033699

RESUMEN

BACKGROUND: Due to work pressure, work intensity, and the impact of emergencies such as the epidemic, job burnout and mental health problems among medical staff have become increasingly prominent. OBJECTIVES: Our study aims to characterize the patterns of burnout in Chinese medical staff, explore the profile differences on anxiety and self-esteem, examine whether the differences in these profiles on anxiety were mediated by self-esteem, and investigate whether this mediating process was moderated by positive coping styles among medical staff. METHODS: Data were collected from 602 medical staff in China by a convenient sampling method. A latent profile and moderated mediation analysis were performed. RESULTS: Latent profile analysis on three burnout dimensions [emotional exhaustion, cynicism, and professional efficacy] indicated two burnout profiles: low burnout (82.47% of the sample) and high burnout (17.53%). Medical staff with a low burnout profile had lower levels of emotional exhaustion and cynicism than those with a high burnout profile. It was also determined that self-esteem mediates burnout and anxiety in both high- and low-burnout medical staff. The moderating role of positive coping styles was also identified (ß = 0.30, 95%CI: 0.058-0.550). CONCLUSIONS: The identification of two distinct burnout patterns (low burnout and high burnout) provides clinical administrators with clear goals for individualizing support and interventions for medical staff with different levels of burnout. Furthermore, attention should be given to self-esteem and positive coping styles, as they act as potential mediators and moderators of medical staff's mental health problems.

2.
Psychol Res Behav Manag ; 17: 1221-1230, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38524281

RESUMEN

Purpose: Although insecure parental attachment (IPA) has been shown to play an important role in anxiety, little is known about the mediating and moderating mechanisms underlying this relationship. Patients and Methods: In the present study, we examined the mediating role of subjective well-being (SWB) in the association between IPA and anxiety and the moderating role of self-esteem. 947 Chinese vocational college students completed the measures of IPA, anxiety, SWB, and self-esteem. Results: The results indicated that IPA was significantly and positively associated with anxiety, and SWB partially mediated this relationship. Moreover, the results indicated that self-esteem moderated the relationship between IPA and anxiety. The higher the level of self-esteem, the weaker the effect of insecure attachment on the anxiety of vocational college students. Conclusion: This study highlights the significance of identifying the mechanisms of mediating and moderating paths between IPA and anxiety in vocational college students.

3.
J Affect Disord ; 325: 633-639, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36640809

RESUMEN

BACKGROUND: Although the relationship between burnout and depression is well-known and frequently studied, the specific mechanisms by which burnout develops into depression have not been fully established. Based on theoretical and empirical research on resilience and self-esteem, this study constructs a chain mediating model to test whether they play a mediating role in burnout and depression among medical staff. METHODS: A cross-sectional study with a sample consisting of 602 medical staff was carried out by convenient sampling method. They all completed a self-report questionnaire with demographic information, burnout, resilience, self-esteem and depression. SPSS26 and Mplus8.3 were used to analyze the data. RESULTS: Burnout was found to positively predict depression of medical staff and negatively predict resilience and self-esteem. Resilience was a mediator between burnout and depression. Self-esteem was also a mediator between them. Meanwhile, resilience and self-esteem had a chain mediating effect on burnout and depression. LIMITATIONS: The cross-sectional study does not permit causal inferences. And the data used is self-reported. CONCLUSIONS: Burnout takes a toll on resilience and self-esteem, which can eventually lead to depression. These findings contribute to the understanding of the predictive effects of burnout on mental health and provide practical implications for the prevention and intervention of mental health among medical staff.


Asunto(s)
Agotamiento Profesional , Resiliencia Psicológica , Humanos , Estudios Transversales , Autoimagen , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , Cuerpo Médico
4.
ACS Appl Mater Interfaces ; 14(17): 19826-19835, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35438973

RESUMEN

Lanthanide-doped upconversion nanoparticles (UCNPs) as energy donors for Förster resonance energy transfer (FRET) are promising in biosensing, bioimaging, and therapeutic applications. However, traditional FRET-based UC nanoprobes show low efficiency and poor sensitivity because only partial activators in UCNPs possessing suitable distance with energy acceptors (<10 nm) can activate the FRET process. Herein, a novel excited-state energy distribution-modulated upconversion nanostructure is explored for highly efficient FRET. Integration of the optimal 4% Er3+ doped shell and 100% Yb3+ core achieves ∼4.5-fold UC enhancement compared with commonly used NaYF4:20%Yb3+,2%Er3+ nanoparticles, enabling maximum donation of excitation energy to an acceptor. The spatial confinement strategy shortens significantly the energy-transfer distance (∼4.5 nm) and thus demonstrates experimentally a 91.9% FRET efficiency inside the neutral red (NR)-conjugated NaYbF4@NaYF4:20%Yb3+,4%Er3+ nanoprobe, which greatly outperforms the NaYbF4@NaYF4:20%Yb3+,4%Er3+@SiO2@NR nanoprobe (27.7% efficiency). Theoretical FRET efficiency calculation and in situ single-nanoparticle FRET measurement further confirm the excellent energy-transfer behavior. The well-designed nanoprobe shows a much lower detection limit of 0.6 ng/mL and higher sensitivity and is superior to the reported NO2- probes. Our work provides a feasible strategy to exploit highly efficient FRET-based luminescence nanoprobes for ultrasensitive detection of analytes.

5.
Cell Death Discov ; 8(1): 60, 2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35149697

RESUMEN

Epithelial ovarian cancer (EOC) is one of the most frequent and fatal gynecologic malignant tumors resulting in an unsatisfying prognosis. Long non-coding RNAs (lncRNAs) play pivotal roles in the tumorigenesis and progression of EOC. However, the profile of lncRNAs involved in EOC remains to be expanded to further improve clinical treatment strategy. In present study, we identified a novel tumor-suppressive lncRNA small nucleolar RNA host gene 10 (SNHG10) in EOC. Kaplan-Meier analysis and COX proportional hazard progression model showed that low expression of SNHG10 was correlated with a poor prognosis of EOC patients. Overexpressing SNHG10 suppressed the proliferation, colony formation, migration, and invasion of EOC cells. Furthermore, SNHG10 was predicted to sponge miR-200a-3p in EOC cells according to the LncBase v.2 experimental module. Then, the binding of SNHG10 and miR-200a-3p was confirmed by performing quantitative real-time PCR (qRT-PCR) and luciferase reporter assays. RNA immunoprecipitation (RIP) showed that SNHG10 and miR-200a-3p occupied the same Ago2 protein to form an RNA-induced silencing complex (RISC). By overlapping the results from the bioinformatics algorithms, tumor-suppressor bridging integrator-1 (BIN1) was found to be a main downstream target of the SNHG10/miR-200a-3p axis. Low expression of BIN1 in EOC tissues was detected by using immunohistochemistry (IHC). Besides, BIN1 and SNHG10 expression was positively correlated in EOC tissues. By performing miRNA rescue experiments, a SNHG10/miR-200a-3p/BIN1 axis and its promoting effects on malignant behaviors and epithelial-mesenchymal transition (EMT) process were verified in EOC cells. Moreover, SNHG10 overexpression significantly suppressed the tumorigenesis and EMT of EOC cells in vivo. Altogether, SNHG10 sponges miR-200a-3p to upregulate BIN1 and thereby exerting its tumor-suppressive effects in EOC. Therefore, the SNHG10/miR-200a-3p/BIN1 axis may act as a potential predictive biomarker and therapeutic target for treating EOC.

6.
ACS Appl Mater Interfaces ; 11(45): 42455-42461, 2019 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-31647642

RESUMEN

Noncontact optical thermometers based on the luminescence intensity ratio of two thermally coupled energy levels, exhibiting high sensitivity, excellent accuracy, fast response, and low environment dependence, have attracted great interests in scientific research, life activities, and industrial manufacturing processes. However, the use of optical thermometers in extreme atmospheres (below 150 K) is usually limited by the required large temperature activation because of the relatively big energy difference (200 cm-1 ≤ ΔE ≤ 2000 cm-1). Here, we propose a strategy to alleviate the ultralow temperature-sensing problem by exploiting and utilizing the near-infrared (NIR) thermally coupled Stark sublevels of Tm3+ (3H4|0 → 3H6/3H4|1 → 3H6, ΔE ≈ 300 cm-1) that is much sensitive to minimal temperature variation, especially at ultralow temperatures because of the tiny energy difference. The integration of ultralow temperature-sensitive Tm3+ ions and room-temperature-sensitive Er3+ ions in an ultrasmall α-NaYbF4:Tm3+@CaF2@NaYF4:Yb3+/Er3+@CaF2 core/multishell nanoparticle (∼15 nm) as a dual-mode upconversion luminescent nanoprobe enables the broad-range temperature detection from 10 to 295 K. This structure induces ∼14 times NIR emission and ∼sixfold green upconversion luminescence output in comparison with the α-NaYbF4:Tm3+ core and α-NaYbF4:Tm3+@CaF2@NaYF4:Yb3+/Er3+ core/shell/shell nanoparticles. The maximum absolute and relative sensitivities of this dual-mode temperature sensor reach 0.67% and 3.06% K-1, respectively, showing the advantage of the concurrent utilization of the Tm3+ NIR 801/820 nm band ratio and the typical Er3+ visible 521/538 nm band ratio for a wide-range temperature-sensing purpose. This work provides a promising strategy to develop accurate and effective, contactless broad-range/ultralow temperature sensors.

7.
Nanoscale ; 9(30): 10633-10638, 2017 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-28656192

RESUMEN

Lanthanide-doped upconversion nanoparticles (UCNPs) have attracted interest for use in bioimaging, biosensing, and therapeutic applications. These motivations are empowered by multicolor upconversion luminescence (UCL) under single near infrared wavelength excitation at ∼980 nm. However, this wavelength overlaps with the absorption peak of water that is dominant in the biological environment, eliciting a serious biological heating problem. This study reports tailored multicolor UCL from a Nd3+-sensitized sandwich-structure of core/shell/shell UCNPs of NaYbF4:0.5%Tm,1%Nd@ CaF2:30%Nd@CaF2:1%Nd,20%Yb,2%Er that can be excited at single wavelength of ∼800 nm without producing any local heating. Incorporation of substantial Nd3+ sensitizers in the middle shell region allows efficient harvesting of excitation light, with the excitation then migrating bidirectionally across the core/shell interfaces to simultaneously activate blue emission from Tm in the core as well as green and red emission from Er in the outermost shell layer. By precise control of the content of lanthanide ions in each domain, a palette of multicolor UCL can be produced, ranging from blue to white. The described Nd3+-sensitized multicolor UCNPs hold promises for a variety of multiplexed biological applications, without complications from heating effects.

8.
Nanoscale ; 9(20): 6711-6715, 2017 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-28485432

RESUMEN

The inability to utilize near infrared (NIR) light has posed a stringent limitation for the efficiencies of most single-junction photovoltaic cells such as dye-sensitized solar cells (DSSCs). Here, we describe a strategy to alleviate the NIR light harvesting problem by upconverting non-responsive NIR light in a broad spectral range (over 190 nm, 670-860 nm) to narrow solar-cell-responsive visible emissions through incorporated dye-sensitized upconversion nanoparticles (DSUCNPs). Unlike typically reported UCNPs with narrow and low NIR absorption, the organic dyes (IR783) anchored on the DSUCNP surface were able to harvest NIR photons broadly and efficiently, and then transfer the harvested energy to the inorganic UCNPs (typically reported), entailing an efficient visible upconversion. We show that the incorporation of DSUCNPs into the TiO2 photoanode of a DSSC is able to elevate its efficiency from 7.573% to 8.568%, enhancing the power conversion efficiency by about 13.1%. We quantified that among the relative efficiency increase, 7.1% arose from the contribution of broad-band upconversion in DSUCNPs (about ∼3.4 times higher than the highest previously reported value of ∼2.1%), and 6.0% mainly from the scattering effect of DSUCNPs. Our strategy has immediate implications for the use of DSUCNPs to improve the performance of other types of photovoltaic devices.

9.
Nanomaterials (Basel) ; 7(2)2017 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-28336867

RESUMEN

The ability to synthesize high-quality hierarchical core/shell nanocrystals from an efficient host lattice is important to realize efficacious photon upconversion for applications ranging from bioimaging to solar cells. Here, we describe a strategy to fabricate multicolor core @ shell α-NaLuF4:Yb3+/Ln3+@CaF2 (Ln = Er, Ho, Tm) upconversion nanocrystals (UCNCs) based on the newly established host lattice of sodium lutetium fluoride (NaLuF4). We exploited the liquid-solid-solution method to synthesize the NaLuF4 core of pure cubic phase and the thermal decomposition approach to expitaxially grow the calcium fluoride (CaF2) shell onto the core UCNCs, yielding cubic core/shell nanocrystals with a size of 15.6 ± 1.2 nm (the core ~9 ± 0.9 nm, the shell ~3.3 ± 0.3 nm). We showed that those core/shell UCNCs could emit activator-defined multicolor emissions up to about 772 times more efficient than the core nanocrystals due to effective suppression of surface-related quenching effects. Our results provide a new paradigm on heterogeneous core/shell structure for enhanced multicolor upconversion photoluminescence from colloidal nanocrystals.

10.
Nanoscale ; 9(1): 91-98, 2017 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-27929179

RESUMEN

The ability to fabricate lanthanide-doped upconversion nanocrystals (UCNCs) with tailored size and emission profile has fuelled their uses in a broad spectrum of biological applications. Yet, limited success has been met in the preparation of sub-6 nm UCNCs with efficient upconversion photoluminescence (UCPL), which enable high contrast optical bioimaging with minimized adverse biological effects entailed by size-induced rapid clearance from the body. Here, we present a simple and reproducible approach to synthesize a set of monodispersed hexagonal-phase core NaGdF4:Yb/Ln (Ln = Er, Ho, Tm) of ∼3-4 nm and core/shell NaGdF4:Yb/Ln@NaGdF4 (Ln = Er, Ho, Tm) UCNCs of ∼5-6 nm. We show that the core/shell UCNCs can be up to ∼1000 times more efficient than the corresponding core UCNCs due to the effective suppression of surface-related quenching effects for the core. The observation of prolonged PL lifetime for the core/shell than that for the core UCNCs demonstrates the role of the inert shell layer for the protection of the core. The achievement of sub-6 nm NaGdF4 UCNCs with significantly improved luminescence efficiency constitutes a solid step towards high contrast UCPL optical imaging with secured biological safety.

11.
JAMA Facial Plast Surg ; 18(1): 20-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26469879

RESUMEN

IMPORTANCE: The psychological traits of cosmetic surgery patients (CSP) are important for selecting patients and postoperative patient satisfaction. A patient's self-esteem, self-efficacy, and self-assessment affect his or her motivation for cosmetic surgery, but the association among these traits remains unclear, especially in the Asian population. OBJECTIVE: To clarify the association of a patient's psychological traits, decision to undergo cosmetic surgery, and the effectiveness of facial cosmetic surgery on the psychological conditions of young, female Chinese patients. DESIGN, SETTING, AND PARTICIPANTS: Three different groups of young women (aged 18-30 years) from the Plastic Surgery Hospital, Chinese Academy of Medical Sciences, and 7 universities were enrolled from January 1, 2012, through December 31, 2014: CSPs (n = 161), general population controls (GPCs) (n = 355), and facial appearance raters (FARs) (n = 268). The last date of follow-up was January 20, 2015. Patient data from questionnaires were obtained preoperatively and 6 months postoperatively, and the data from the control groups were obtained immediately after enrollment. Front-view facial images of the study participants were taken and then shown to independent raters to assess the participants' facial appearances on a rating scale. MAIN OUTCOMES AND MEASURES: Evaluation of self-esteem and self-efficacy, subjective and objective assessment of facial appearance, and structural equation models. RESULTS: A total of 163 CSPs and 387 GPCs were recruited for the study, and complete and valid data were obtained from 161 CSPs and 355 GPCs. All responses from the 268 FARs met the criteria for subsequent analysis. Of the questionnaires issued to the CSPs 6 months postoperatively, 126 valid responses were returned (response rate, 78.3%). Self-esteem and self-efficacy decreased significantly in preoperative patients compared with controls (P < .001) (mean [SD] scores, 22.60 [1.80] for CSPs and 27.39 [2.11] for GPCs for self-esteem and 21.50 [2.40] for CSPs and 28.59 [4.23] for GPCs for self-efficacy) and were found to be at nearly normal levels 6 months postoperatively (mean [SD] scores, 25.88 [3.65] and 26.38 [2.45] for self-esteem and self-efficacy, respectively). The patients' objective assessments of facial appearance did not differ significantly from those of the control group participants (mean [SD] scores, 4.51 [0.77] and 4.55 [0.74] for CSPs and GPCs, respectively; P = .86); however, a significant decrease in patient self-assessment was noted (mean [SD scores], 6.45 [1.15] and 7.31 [1.42] for CSPs and GPCs, respectively; P = .01). Moreover, the structural equation models revealed a path from low self-esteem and self-efficacy after decreased self-assessment to decision for cosmetic surgery. CONCLUSIONS AND RELEVANCE: Self-esteem and self-efficacy mediate the negative effects of self-assessment on the decision of young women to undergo facial cosmetic surgery. The impairment of self-esteem and self-efficacy may indicate the need for preoperative psychological intervention. Facial cosmetic surgery can have positive effects on self-esteem and self-efficacy. LEVEL OF EVIDENCE: 2.


Asunto(s)
Pueblo Asiatico/psicología , Blefaroplastia/psicología , Satisfacción del Paciente , Rinoplastia/psicología , Autoimagen , Adolescente , Adulto , China , Femenino , Estudios de Seguimiento , Humanos , Estudios Prospectivos , Autoeficacia , Autoevaluación (Psicología) , Adulto Joven
12.
Nanoscale ; 7(24): 10775-80, 2015 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-26035440

RESUMEN

We report on heterogeneous core/shell CaF2:Yb(3+)/Ho(3+)@NaGdF4 nanocrystals of 17 nm with efficient upconversion (UC) photoluminescence (PL) for in vivo bioimaging. Monodisperse core/shell nanostructures were synthesized using a seed-mediated growth process involving two quite different approaches of liquid-solid-solution and thermal decomposition. They exhibit green emission with a sharp band around 540 nm when excited at ∼980 nm, which is about 39 times brighter than the core CaF2:Yb(3+)/Ho(3+) nanoparticles. PL decays at 540 nm revealed that such an enhancement arises from efficient suppression of surface-related deactivation from the core nanocrystals. In vivo bioimaging employing water-dispersed core/shell nanoparticles displayed high contrast against the background.


Asunto(s)
Medios de Contraste/síntesis química , Fluoruros/química , Mediciones Luminiscentes/métodos , Microscopía/métodos , Nanopartículas/química , Imagen de Cuerpo Entero/métodos , Animales , Aumento de la Imagen/métodos , Ratones , Nanopartículas/ultraestructura , Tamaño de la Partícula
13.
Nanomaterials (Basel) ; 5(1): 218-232, 2015 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-28347007

RESUMEN

Hexagonal NaYF4:Nd3+/Yb3+/Er3+ microcrystals and nanocrystals with well-defined morphologies and sizes have been synthesized via a hydrothermal route. The rational control of initial reaction conditions can not only result in upconversion (UC) micro and nanocrystals with varying morphologies, but also can produce enhanced and tailored upconversion emissions from the Yb3+/Er3+ ion pairs sensitized by the Nd3+ ions. The increase of reaction time converts the phase of NaYF4:Nd3+/Yb3+/Er3+ particles from the cubic to the hexagonal structure. The added amount of oleic acid plays a critical role in the shape evolution of the final products due to their preferential attachment to some crystal planes. The adjustment of the molar ratio of F-/Ln3+ can range the morphologies of the ß-NaYF4:Nd3+/Yb3+/Er3+ microcrystals from spheres to nanorods. When excited by 808 nm infrared laser, ß-NaYF4:Nd3+/Yb3+/Er3+ microplates exhibit a much stronger UC emission intensity than particles with other morphologies. This phase- and morphology-dependent UC emission holds promise for applications in photonic devices and biological studies.

14.
Nanomaterials (Basel) ; 5(4): 1782-1809, 2015 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-28347095

RESUMEN

Photovoltaic cells are able to convert sunlight into electricity, providing enough of the most abundant and cleanest energy to cover our energy needs. However, the efficiency of current photovoltaics is significantly impeded by the transmission loss of sub-band-gap photons. Photon upconversion is a promising route to circumvent this problem by converting these transmitted sub-band-gap photons into above-band-gap light, where solar cells typically have high quantum efficiency. Here, we summarize recent progress on varying types of efficient upconversion materials as well as their outstanding uses in a series of solar cells, including silicon solar cells (crystalline and amorphous), gallium arsenide (GaAs) solar cells, dye-sensitized solar cells, and other types of solar cells. The challenge and prospect of upconversion materials for photovoltaic applications are also discussed.

15.
Nanoscale ; 6(2): 753-7, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24309589

RESUMEN

Intense ultraviolet upconversion emission has been observed in water-dispersed uniform rhombic nanodisks (side length of ~14 nm and thickness of ~2.5 nm) of YF3 co-doped with Yb(3+) sensitizer and Tm(3+) activator ions, when excited at ~980 nm.

16.
Theranostics ; 3(5): 331-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23650480

RESUMEN

Optical sensing plays an important role in theranostics due to its capability to detect hint biochemical entities or molecular targets as well as to precisely monitor specific fundamental psychological processes. Rare-earth (RE) doped upconversion nanoparticles (UCNPs) are promising for these endeavors due to their unique frequency converting capability; they emit efficient and sharp visible or ultraviolet (UV) luminescence via use of ladder-like energy levels of RE ions when excited at near infrared (NIR) light that are silent to tissues. These features allow not only a high penetration depth in biological tissues but also a high detection sensitivity. Indeed, the energy transfer between UCNPs and biomolecular or chemical indicators provide opportunities for high-sensitive bio- and chemical-sensing. A temperature-sensitive change of the intensity ratio between two close UC bands promises them for use in temperature mapping of a single living cell. In this work, we review recent investigations on using UCNPs for the detection of biomolecules (avidin, ATP, etc.), ions (cyanide, mecury, etc.), small gas molecules (oxygen, carbon dioxide, ammonia, etc.), as well as for in vitro temperature sensing. We also briefly summarize chemical methods in synthesizing UCNPs of high efficiency that are important for the detection limit.


Asunto(s)
Técnicas Biosensibles/métodos , Metales de Tierras Raras/síntesis química , Animales , Fluoruros , Gases/análisis , Humanos , Luminiscencia , Nanopartículas/química , Nanopartículas/ultraestructura
17.
Opt Lett ; 37(7): 1268-70, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22466217

RESUMEN

Important for telecommunications, luminescence of trivalent erbium (Er) at 1.5 µm generally arises from a Stokes-shifted downconversion mechanism. We show that this luminescence following direct excitation of the 4I11/2 state is generated by upconversion-mediated looping process in Er3+/Sc3+-codoped LiNbO3 single crystal. Emissions at 1.0 and 1.5 µm from the 4I11/2 and 4I13/2 states display linear and quadratic dependences on the excitation density in two separated ranges with a threshold of 20 W/cm2. This observation correlates with two- and four-photon processes in green and red upconversion emissions. The mechanism described has implications in the improvement of the output of 1.5 µm luminescence.


Asunto(s)
Erbio/química , Luminiscencia , Niobio/química , Óxidos/química , Escandio/química , Láseres de Semiconductores , Espectrometría de Fluorescencia
18.
J Nanosci Nanotechnol ; 11(9): 7700-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22097476

RESUMEN

Cubic nanocrystal and hexagonal micro-rods NaYF4, with predictable size, shape and phase, have been successfully synthesized through hydrothermal reaction. The growth mechanism and the effect of mass transfer on the morphology of hexagonal micro-prism are both discussed in detail. The increase of tri-doping lanthanide ion concentration decreased the size of crystal particle, which was explained by the Arrhenius rate equation together combined with the Gibbs-Thomson relationship. Furthermore, the dopants did not only affect the sizes of tri-doped NaYF4 micro-rods, but also impacted upon fluorescence intensity. The fluorescence of tri-doped NaYF4: Nd3+/Yb3+/Er3+ system, excited by an 800 nm femtolaser, was intensified with the increase of doped lanthanide ions concentration. Nevertheless owing to the fluorescence quenching, the other two systems (NaYF4: Nd3+/Ho3+/Er3+ and NaYF4: Nd3+/Tm3+/Er3+) did not show the same phenomenon.

19.
Chem Commun (Camb) ; 47(34): 9648-50, 2011 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-21799971

RESUMEN

We present a simple method to gradually tune the size and to induce the shape change of CeO(2) nanoparticles via increasing the content of Yb(3+) doping.


Asunto(s)
Cerio/química , Nanopartículas/química , Nanotecnología/métodos , Tamaño de la Partícula , Iterbio/química , Coloides
20.
Zhonghua Nan Ke Xue ; 14(6): 538-41, 2008 Jun.
Artículo en Chino | MEDLINE | ID: mdl-18649755

RESUMEN

OBJECTIVE: To evaluate the sex therapy for erectile dysfunction (ED). METHODS: We recommended the sex therapy to ED patients and their partners (11 couples in all) in the outpatient department. Of the total number of volunteers, 2 males were accompanied by ejaculation disorder, another 2 with hyposexuality, and 1 female had vaginismus. The effect of the therapy was assessed and the problems with it analyzed by interviews with the subjects and the results of International Index of Erectile Function (IIEF) before and after the treatment. RESULTS: Of the 11 pairs of volunteers, 5 quitted halfway and 1 discontinued at the therapists' decision. The 5 couples who accomplished the whole therapy felt more satisfied with their sexual life and general relationship, with improved scores on all the items of IIEF, particularly on erectile function (EF), with the only exception of sexual desire (SD). CONCLUSION: The sex therapy is effective not only for ED but also for other accompanying sexual dysfunctions, the sexual dysfunctions of the patients' partners and the improvement of the general relationship of the couples.


Asunto(s)
Terapia Conductista/métodos , Disfunción Eréctil/terapia , Conducta Sexual , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Parejas Sexuales , Resultado del Tratamiento
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