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1.
iScience ; 27(9): 110794, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39297174

RESUMEN

Metal halide perovskite nanomaterials (PeNMs) are among the next generation of optoelectronic materials due to their unique crystal structure and diverse phase change behaviors, which have the potential to dynamically tune the device performances. In this review, the research progress on the phase change of PeNMs is comprehensively reviewed and summarized. First, the basic structure and composition, as well as the phase change mechanism are introduced. Then, the influence of the phase change on the optoelectronic properties of PeNMs is discussed in detail, including the regulation of the energy band structure, carrier transport properties, lattice strain and distortion, and the evolution of the photoexcited state. Finally, current challenges and future development trends are projected. This review promotes the understanding of the phase change of PeNMs, which will be useful for the innovative design and application of related optoelectronic devices.

2.
Nanoscale ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39224054

RESUMEN

Controlling the random lasing action from disordered media is important to obtain customizable lasers with unprecedented properties. In this paper, systematic investigations of random scattering based on GaAs/AlGaAs axial heterostructure nanowire (NW) arrays are presented. By manipulating the diameter and density of GaAs/AlGaAs axial heterostructure NWs during growth, different types of random lasers (Anderson localized and delocalized random lasers) have been successfully realized. The threshold, Q factor, and spatial coherence of these two types of lasers are experimentally discussed and analyzed. Finally, a proof-of-concept demonstration of speckle-free imaging based on the NW lasers has been conducted. This research enables the tunability of random lasers with exceptional performance and lays the foundation for achieving random lasing control.

3.
Behav Sci (Basel) ; 14(8)2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39199095

RESUMEN

Increased aggression due to gaming addiction is a widespread and highly publicized problem. The underlying processes by which verbal aggression, a more harmful and persistent subcategory of aggression, is affected by gaming addiction may differ from other types of aggression. In this study, data came from 252 randomly recruited current university students (50.79% male, mean age 19.60 years, SD: 1.44 years, range 17 to 29 years). Participants reported gaming addiction and different types of aggression through questionnaires. In addition, two important explanatory processes, inhibitory control, and risk preference, were measured through behavioral experiments. A Bayesian hierarchical drift-diffusion model was employed to interpret the data from the risk preference task. In contrast to previous work, the study found that inhibitory control did not significantly correlate with either gaming addiction or any form of aggression However, the drift rate, a measure of decision-making inclination under risk, partially mediates the relationship between gaming addiction and verbal aggression (but not other forms of aggression). The findings illuminate risk preference under adverse conditions as a key predictor of verbal aggression, offering avenues for early intervention and suggesting game design modifications to mitigate verbal aggression by adjusting reward mechanisms.

4.
ACS Nano ; 18(35): 24024-24034, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39167054

RESUMEN

In recent years, there has been considerable push toward the biomedical applications with active particles, which have great potential to revolutionize disease diagnostics and therapy. The direct penetration of active particles through the cell membrane leads to more efficient intracellular delivery than previously considered endocytosis processes but may cause membrane disruption. Understanding fundamental behaviors of cell membranes in response to such extreme impacts by active particles is crucial to develop active particle-based biomedical technologies and manage health and safety issues in this emerging field. Unfortunately, the physical principles underlying the nonequilibrium behaviors from endocytosis to direct penetration remain elusive, and experiments are challenging. Here, we present a computed dynamic phase diagram for transmembrane transport of active particles and identify four characteristic dynamic phases in endocytosis and direct penetration according to the particle activity and membrane tension. The boundaries dividing these phases are analytically obtained with theoretical models, elucidating the nonequilibrium physics and criteria for the transition between different phases. Furthermore, we numerically and experimentally show three distinct dynamic regimes related to the interplay between necking and wrapping during the endocytosis process of active particles, which strikingly contrast the regimes for passive particles. Overall, these findings could be useful for sharpening the understanding of basic principles underlying biological issues related to the safe and efficient biomedical applications of such emerging matters.


Asunto(s)
Membrana Celular , Endocitosis , Membrana Celular/metabolismo , Membrana Celular/química , Transporte Biológico , Humanos , Modelos Biológicos , Tamaño de la Partícula
5.
Nat Commun ; 15(1): 5696, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38972890

RESUMEN

Even though lead halide perovskite has been demonstrated as a promising optoelectronic material for next-generation display applications, achieving high-efficiency and stable pure-red (620~635 nm) emission to cover the full visible wavelength is still challenging. Here, we report perovskite light-emitting diodes emitting pure-red light at 628 nm achieving high external quantum efficiencies of 26.04%. The performance is attributed to successful synthesizing strongly confined CsPbI3 quantum dots with good stability. The strong binding 2-naphthalene sulfonic acid ligands are introduced after nucleation to suppress Ostwald ripening, meanwhile, ammonium hexafluorophosphate exchanges long chain ligands and avoids regrowth by strong binding during the purification process. Both ligands enhance the charge transport ability of CsPbI3 quantum dots. The state-of-the-art synthesis of pure red CsPbI3 quantum dots achieves 94% high quantum efficiency, which can maintain over 80% after 50 days, providing a method for synthesizing stable strong confined perovskite quantum dots.

6.
ACS Appl Mater Interfaces ; 16(31): 41677-41683, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39069675

RESUMEN

Room-temperature lasing based on low-dimensional GaAs nanowires (NWs) is one of the most critical and challenging issues in realizing near-infrared lasers for nanophotonics. In this article, the random lasing characteristics based on GaAs NW arrays have been discussed theoretically. According to the simulation, GaAs/AlGaAs core-shell NWs with an optimal diameter, density, and Al content in the shell have been grown. Systematic morphological and optical characterizations were carried out. It is found that the GaAs NWs with the additional growth of the AlGaAs shell exhibit improved emission by about 2 orders of magnitude at low temperatures, which can be attributed to the suppression of crystal defects. At room temperature, lasing was observed with a threshold around 70.16 mW/cm2, and the random lasing mechanism was discussed in detail. This work is of great significance for the design of random cavities based on semiconductor NWs, which is important for optoelectronic integration.

7.
Front Cell Infect Microbiol ; 14: 1402001, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39035352

RESUMEN

Viral hepatitis, caused by its etiology, hepatitis virus, is a public health problem globally. Among all infections caused by hepatitis-associated viruses, hepatitis B virus (HBV) infection remains the most serious medical concern. HBV infection particularly affects people in East Asia and Africa, the Mediterranean region, and Eastern Europe, with a prevalence rate of > 2%. Currently, approximately 1 billion people worldwide are infected with HBV, and nearly 30% of them experience chronic infection. Chronic HBV infection can lead to chronic hepatitis B (CHB), liver cirrhosis, and hepatocellular carcinoma (HCC), resulting in the related death of approximately 1 million people annually. Although preventative vaccines and antiviral therapies are currently available, there is no cure for this infection. Clinical testing is not only the gateway for diagnosis of HBV infection, but also crucial for judging the timing of medication, evaluating the effect of antiviral therapy, and predicting the risk of relapse after drug withdrawal in the whole follow-up management of hepatitis B infected persons. With advances in detection technology, it is now possible to measure various viral components in the blood to assess the clinical status of HBV infection. Serum viral products of HBV infection, such as HBV DNA, HBV RNA, hepatitis B surface antigen, hepatitis B e-antigen, and hepatitis B core-related antigen, are non-invasive indicators that are critical for the rapid diagnosis and management of related diseases. Improving the sensitivity of monitoring of these products is essential, and the development of corresponding detection technologies is pivotal in achieving this goal. This review aims to offer valuable insights into CHB infection and references for its effective treatment. We provide a comprehensive and systematic overview of classical and novel methods for detecting HBV serum viral products and discusses their clinical applications, along with the latest research progress in this field.


Asunto(s)
ADN Viral , Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , ADN Viral/sangre , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Hepatitis B/diagnóstico , Hepatitis B/tratamiento farmacológico , ARN Viral/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Antivirales/uso terapéutico
8.
Lipids Health Dis ; 23(1): 147, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760818

RESUMEN

BACKGROUND: Omega-3 polyunsaturated fatty acids (omega-3 PUFAs) exhibit potential as therapeutics for a variety of diseases. This observational and Mendelian randomization (MR) study aims to explore the relationship between omega-3 PUFAs and osteoarthritis (OA). METHODS: Excluding individuals under 20 years old and those with missing data on relevant variables in the National Health and Nutrition Examination Survey (NHANES) spanning from 2003 to 2016, a total of 22 834 participants were included in this cross-sectional study. Weighted multivariable-adjusted logistic regression was used to estimate the association between omega-3 PUFAs and OA in adults. Moreover, restricted cubic splines were utilized to examine the dose-response relationship between omega-3 PUFAs and OA. To further investigate the potential causal relationship between omega-3 PUFAs and OA risk, a two-sample MR study was conducted. Furthermore, the robustness of the findings was assessed using various methods. RESULTS: Omega-3 PUFAs intake were inversely associated with OA in adults aged 40 ∼ 59 after multivariable adjustment [Formula: see text], with a nonlinear relationship observed between omega-3 PUFAs intake and OA [Formula: see text]. The IVW results showed there was no evidence to suggest a causal relationship between omega-3 PUFAs and OA risk [Formula: see text]. CONCLUSIONS: Omega-3 PUFAs were inversely associated with OA in adults aged 40 ∼ 59. However, MR studies did not confirm a causal relationship between the two.


Asunto(s)
Ácidos Grasos Omega-3 , Análisis de la Aleatorización Mendeliana , Encuestas Nutricionales , Osteoartritis , Humanos , Osteoartritis/genética , Osteoartritis/epidemiología , Ácidos Grasos Omega-3/administración & dosificación , Masculino , Persona de Mediana Edad , Femenino , Adulto , Estudios Transversales , Factores de Riesgo
9.
Nanomicro Lett ; 16(1): 105, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300363

RESUMEN

CsPbI3 perovskite quantum dots (QDs) are ideal materials for the next generation of red light-emitting diodes. However, the low phase stability of CsPbI3 QDs and long-chain insulating capping ligands hinder the improvement of device performance. Traditional in-situ ligand replacement and ligand exchange after synthesis were often difficult to control. Here, we proposed a new ligand exchange strategy using a proton-prompted in-situ exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI3 QDs. This exchange strategy maintained the size and morphology of CsPbI3 QDs and improved the optical properties and the conductivity of CsPbI3 QDs films. As a result, high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45% and an operational half-life of 10.79 h.

10.
ACS Appl Mater Interfaces ; 16(9): 11715-11721, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38382471

RESUMEN

Inverted perovskite light-emitting diodes (PeLEDs) based on quantum dots (QDs) are some of the most promising candidates for next-generation lighting and display applications. Due to the strong fluorescence quenching caused by zinc oxide, high performance in such inverted devices remains challenging. Here, we report an efficient inverted green CsPbBr3 QDs LED using an emitting buffer layer. Ultrathin CsPbBr3 QD emitters act as the buffer layer to reduce the interface luminescence quenching reaction at the ZnO/upper emitting layer interface, increasing the probability of exciton recombination within the emissive layer and regulating the charge transport, leading to effective carrier recombination. The resulting device exhibits an external quantum efficiency of 13.1%, enhanced by about 4.7 times compared with that without a buffer layer device. This work provides a path to fabricating high-performance inverted PeLEDs.

11.
Nat Commun ; 15(1): 525, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38225267

RESUMEN

Transport of rodlike particles in confinement environments of macromolecular networks plays crucial roles in many important biological processes and technological applications. The relevant understanding has been limited to thin rods with diameter much smaller than network mesh size, although the opposite case, of which the dynamical behaviors and underlying physical mechanisms remain unclear, is ubiquitous. Here, we solve this issue by combining experiments, simulations and theory. We find a nonmonotonic dependence of translational diffusion on rod length, characterized by length commensuration-governed unconventionally fast dynamics which is in striking contrast to the monotonic dependence for thin rods. Our results clarify that such a fast diffusion of thick rods with length of integral multiple of mesh size follows sliding dynamics and demonstrate it to be anomalous yet Brownian. Moreover, good agreement between theoretical analysis and simulations corroborates that the sliding dynamics is an intermediate regime between hopping and Brownian dynamics, and provides a mechanistic interpretation based on the rod-length dependent entropic free energy barrier. The findings yield a principle, that is, length commensuration, for optimal design of rodlike particles with highly efficient transport in confined environments of macromolecular networks, and might enrich the physics of the diffusion dynamics in heterogeneous media.

12.
Small ; 20(25): e2307360, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38217294

RESUMEN

Ion diffusion is a fundamentally important process in understanding and manipulating the optoelectronic properties of semiconductors. Most current studies on ionic diffusion have been focusing on perovskite polycrystalline thin films and nanocrystals. However, the random orientation and grain boundaries can heavily interfere with the kinetics of ion diffusion, where the experimental results only reveal the average ion exchange kinetics and the actual ion diffusion mechanisms perpendicular to the direction of individual crystal facets remain unclear. Here, the anion (Cl, I) diffusion anisotropy on (111) and (100) facets of CsPbBr3 single crystals is demonstrated. The as-grown single crystals with (111) and (100) facets exhibit anisotropic growth with different halide incorporation, which lead to different resulting optoelectronic properties. Combined experimental characterizations and theoretical calculations reveal that the (111) CsPbBr3 shows a faster anion diffusion behavior compared with that of the (100) CsPbBr3, with a lower diffusion energy barrier, a larger built-in electric field, and lower inverse defect formation energy. The work highlights the anion diffusion anisotropic mechanisms perpendicular to the direction of individual crystal facets for optimizing and designing perovskite optoelectronic devices.

13.
JMIR Serious Games ; 11: e48317, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37990585

RESUMEN

Background: The question of how video games can shape aggressive behaviors has been a focus for many researchers. Previous research has focused on how violent video game content leads to postgame aggressive behaviors. However, video games not only convey violence or prosocial content to players but also require cognitive effort from individuals. Since human cognitive resources are limited, consuming more cognitive resources in a game leads to less cognitive resources to suppress aggressive impulses. Therefore, the depletion of cognitive resources from playing video games may also lead to changes in postgame aggressive behaviors. Objective: This study aimed to examine the relationship between cognitive resources consumed in video games and postgame aggressive behaviors. Methods: A total of 60 participants (age: mean 20.22; range 18-24 y) were randomly assigned to either the high-load group or the low-load group. Participants from both groups played a video game centered around college life. In the low-load group, participants followed the gameplay instructions to complete it. In the high-load group, participants were given an extra digital memory task to complete while playing the game. Participants in both groups played the video game for about 25 minutes. A maze selection task was then conducted to measure the participants' helping and hurting behaviors. Results: The independent samples 2-tailed t tests showed that the high-load group had significantly higher hurting scores (mean 3.13, SD 2.47) than the low-load group (mean 1.90, SD 2.12; t58=-2.07, P=.04; Cohen d=-0.535), whereas helping behaviors were not significantly affected (t58=1.52, P=.13; Cohen d=0.393). Conclusions: As more cognitive resources are consumed in a video game, more hurting behaviors are exhibited after the game. This finding proposes an alternative route by which video games impact aggressive behaviors, adding to previous theories and raising concerns about the popularity of cognitive training games.

14.
Heliyon ; 9(10): e20494, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37810846

RESUMEN

The disclosure of work safety information of listed companies in high-risk industries is an important aspect of their social responsibility, and it is also an inevitable requirement to meet the right of stakeholders to know, which has a far-reaching impact on the development of enterprises. In order to clarify the impact mechanism of work safety information disclosure on enterprise performance of listed companies in high-risk industries. 222 listed companies in high-risk industries were taken as the research object, and the multiple regression analysis method was used to analyze the relationship between the level of work safety information disclosure of enterprises and their financial performance, safety performance and social reputation. The results show that the work safety information disclosure of listed companies in high-risk industries has a positive impact on corporate financial performance, safety performance and social reputation; unabsorbed slack resources have a positive U-shaped regulatory effect on work safety information disclosure and enterprise social reputation; The shareholding ratio of institutional investors has an inverted U-shaped regulatory effect on the positive relationship between work safety information disclosure and enterprise social reputation. This study has enriched the theoretical and practical exploration of research on work safety information disclosure. It can help improve the level of work safety information disclosure and safety management in enterprises, while guiding the sustainable development of occupational health and safety within these organizations.

15.
Adv Sci (Weinh) ; 10(36): e2304696, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37890450

RESUMEN

Perovskite nanocrystals for light-emitting diodes are often synthesized by uncontrollable metathesis reactions, suffering from low product yield, nonuniform growth, and poor stability. Herein, by controlling the nucleation kinetics with high dissociation constant (Ka or Kb) acids or bases, homogenous one-route nucleation of perovskite nanocrystals is achieved as the cluster intermediates are eliminated. The stable, shape uniform, and narrow size distribution green nanocrystals are synthesized. The perovskite nanocrystal film exhibites excellent stability in 80% humidity air with only a 10% photoluminescence intensity drop after 16 h. Efficient and stable electroluminescence is demonstrated with an FWHM of 16 nm at 517 nm. The green devices shows a peak EQE of 24.13% with a lifetime T50 of 54 min at 10 000 cd m-2 .

16.
Chem Soc Rev ; 52(19): 6806-6837, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37743794

RESUMEN

Self-assembly of various building blocks has been considered as a powerful approach to generate novel materials with tailorable structures and optimal properties. Understanding physicochemical interactions and mechanisms related to structural formation and transitions is of essential importance for this approach. Although it is well-known that diverse forces and energies can significantly contribute to the structures and properties of self-assembling systems, the potential entropic contribution remains less well understood. The past few years have witnessed rapid progress in addressing the entropic effects on the structures, responses, and functions in the self-assembling systems, and many breakthroughs have been achieved. This review provides a framework regarding the entropy-controlled strategy of self-assembly, through which the structures and properties can be tailored by effectively tuning the entropic contribution and its interplay with the enthalpic counterpart. First, we focus on the fundamentals of entropy in thermodynamics and the entropy types that can be explored for self-assembly. Second, we discuss the rules of entropy in regulating the structural organization in self-assembly and delineate the entropic force and superentropic effect. Third, we introduce the basic principles, significance and approaches of the entropy-controlled strategy in self-assembly. Finally, we present the applications where this strategy has been employed in fields like colloids, macromolecular systems and nonequilibrium assembly. This review concludes with a discussion on future directions and future research opportunities for developing and applying the entropy-controlled strategy in complex self-assembling systems.

17.
Biomed Pharmacother ; 167: 115509, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37722193

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies in the whole world, with little improvement in the 5-year survival rate due to the occurrence of chemoresistance. With the increasing interests in tumor immune microenvironment, immunogenic cell death (ICD)-induced chemotherapy has shown promising results in enhancing sensitivity to immune checkpoint inhibitors (ICI) and improving the efficiency of tumor immunotherapy. This review summarizes the role of key ICD biomarkers and their underlying molecular mechanisms in HNSCC chemoresistance. The results showed that ICD initiation could significantly improve the survival and prognosis of patients. ICD and its biomarker could also serve as molecular markers for tumor diagnosis and prognosis. Moreover, key components of DAMPs including CALR, HGMB1, and ATP are involved in the regulation of HNSCC chemo-sensitivity, confirming that the key biomarkers of ICD can also be developed into new targets for regulating HNSCC chemoresistance. This review clearly illustrates the theoretical basis for the hypothesis that ICD biomarkers are therapeutic targets involved in HNSCC progression, chemoresistance, and even immune microenvironment regulation. The compilation and investigation may provide new insights into the molecular therapy of HNSCC.

18.
Nanoscale ; 15(34): 14140-14145, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37584662

RESUMEN

Two-dimensional colloidal CdSe nanoplatelets (NPLs) have been considered as ideal emitting materials for high performance light-emitting devices due to their excellent optical properties. However, the understanding of defect related radiative and nonradiative recombination centers in CdSe NPLs is still far from sufficient, especially their physical distribution locations. In this work, CdSe core and CdSe/CdS core/crown NPLs have been successfully synthesized and their optical properties have been characterized by laser spectroscopies. It is found that the photoluminescence quantum yield of CdSe NPLs is improved by a factor of 4 after the growth of the CdS crown. At low temperatures, the change in the ratio of low and high energy emission intensities from NPLs suggests that the radiative recombination centers are mainly located on the lateral surface of the samples. This finding is further confirmed by the surface passivation experiment. Meanwhile, the nonradiative recombination centers of NPLs located on the lateral surface are also confirmed by ligand exchange. These results demonstrate the importance of understanding the optical properties of the lateral surface of NPLs, which are important for the design of material structures for optoelectronic applications.

19.
J Phys Chem Lett ; 14(33): 7581-7590, 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37590125

RESUMEN

It is necessary to improve the action cross section (η × σn) of high-order multiphoton absorption (MPA) for fundamental research and practical applications. Herein, the core-shell FAPbBr3/CsPbBr3 nanocrystals (NCs) were constructed, and fluorescence induced by up to five-photon absorption was observed. The value of η × σ5 reaches 8.64 × 10-139 cm10 s4 photon-4 nm-3 at 2300 nm, which is nearly an order of magnitude bigger than that of the core-only NCs. It is found that the increased dielectric constant promotes modulation of MPA effects, addressing the electronic distortion in high-order nonlinear behaviors through the local field effect. Meanwhile, the quasi-type-II band alignment suppresses the biexciton Auger recombination, ensuring the stronger MPA induced fluorescence. In addition, the core-shell structure can not only reduce the defect density but also promote the nonradiative energy transfer though the antenna-like effect. This work provides a new avenue for the exploitation of high-performance multiphoton excited nanomaterials for future photonic integration.

20.
ACS Appl Mater Interfaces ; 15(23): 28833-28839, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37272407

RESUMEN

Perovskite quantum dot light-emitting diodes (QLEDs) are potential candidates for next-generation displays due to their high color purity and wide color gamut. Due to the strong electron-accepting ability of poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), quantum dot (QD) films are prone to be charged, which leads to the imbalance of charge injection and the increase of nonradiative recombination, ultimately affecting the performance of the QLEDs. Here, we compared and studied two polymers, poly(methyl methacrylate) (PMMA) and poly(vinyl pyrrolidone) (PVP), as the hole interface buffer layers of QD films, which effectively reduced the defect density, suppressed nonradiative recombination, and greatly improved the efficiency and stability of QLEDs. The devices with PMMA achieved a maximum external quantum efficiency of 20.71%.

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