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1.
Expert Opin Drug Saf ; 23(4): 497-511, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38556702

RESUMEN

OBJECTIVES: To investigate the risk of hemorrhage associated with Immune Checkpoint Inhibitors (ICIs) and characterize its clinical features. METHODS: We systematically reviewed randomized clinical trials (RCTs) of hemorrhage related to ICIs and calculated odds ratios (ORs) with 95% confidence intervals (CIs). Pharmacovigilance studies were conducted by collecting ICIs-related hemorrhage cases from the FAERS database and assessing disproportionalities by reporting odds ratios (RORs) and information components (ICs). RESULTS: A total of 79 RCTs involving 45,100 patients were finally included in the systematic review, with four published RCTs (n = 1965) and 75 unpublished RCTs (n = 43135). The primary analysis showed no significant difference in ICIs compared to the control group (OR 1.18 [95% CI 1.00-1.38], p = 0.05). In subgroup analyses, anti-PD-L1 combined with anti-CTLA-4 increased the risk of hemorrhage (OR 1.95, p = 0.03), and anti-CTLA-4 increased the risk of hemorrhage in the gastrointestinal system (OR 2.23, p = 0.04). 3555 cases of hemorrhage from the FAERS database were included in the disproportionate analysis, and the result suggested that ICIs increased the risk of hemorrhage (IC025 = 0.23). CONCLUSION: Our study suggests that ICIs increase the risk of hemorrhage, and in particular, anti-CTLA-4 significantly increases the risk of hemorrhage in the gastrointestinal system.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Farmacovigilancia , Humanos , Antígeno CTLA-4 , Bases de Datos Factuales , Hemorragia , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Nat Commun ; 15(1): 2433, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499545

RESUMEN

Nonlinear optical processing of ambient natural light is highly desired for computational imaging and sensing. Strong optical nonlinear response under weak broadband incoherent light is essential for this purpose. By merging 2D transparent phototransistors (TPTs) with liquid crystal (LC) modulators, we create an optoelectronic neuron array that allows self-amplitude modulation of spatially incoherent light, achieving a large nonlinear contrast over a broad spectrum at orders-of-magnitude lower intensity than achievable in most optical nonlinear materials. We fabricated a 10,000-pixel array of optoelectronic neurons, and experimentally demonstrated an intelligent imaging system that instantly attenuates intense glares while retaining the weaker-intensity objects captured by a cellphone camera. This intelligent glare-reduction is important for various imaging applications, including autonomous driving, machine vision, and security cameras. The rapid nonlinear processing of incoherent broadband light might also find applications in optical computing, where nonlinear activation functions for ambient light conditions are highly sought.

3.
J Oral Microbiol ; 15(1): 2196897, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37035450

RESUMEN

Bacterial adhesion to dental materials' surfaces is the initial cause of dental materials-related infections. Therefore, inhibiting bacterial adhesion is a critical step in preventing and controlling these infections. To this end, it is important to know how the properties of dental materials affect the interactions between microorganisms and material surfaces to produce materials without biological contamination. This manuscript reviews the mechanism of bacterial adhesion to dental materials, the relationships between their surface properties and bacterial adhesion, and the impact of bacterial adhesion on their surface properties. In addition, this paper summarizes how these surface properties impact oral biofilm formation and proposes designing intelligent dental material surfaces that can reduce biological contamination.

4.
Adv Mater ; 35(23): e2301533, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36944373

RESUMEN

Hydrazine-assisted water electrolysis offers a feasible path for low-voltage green hydrogen production. Herein, the design and synthesis of ultrathin RhRu0.5 -alloy wavy nanowires as bifunctional electrocatalysts for both the anodic hydrazine oxidation reaction (HzOR) and the cathodic hydrogen evolution reaction (HER) is reported. It is shown that the RhRu0.5 -alloy wavy nanowires can achieve complete electrooxidation of hydrazine with a low overpotential and high mass activity, as well as improved performance for the HER. The resulting RhRu0.5 bifunctional electrocatalysts enable, high performance hydrazine-assisted water electrolysis delivering a current density of 100 mA cm-2 at an ultralow cell voltage of 54 mV and a high current density of 853 mA cm-2 at a cell voltage of 0.6 V. The RhRu0.5  electrocatalysts further demonstrate a stable operation at a high current density of 100 mA cm-2 for 80 hours of testing period with little irreversible degradation. The overall performance greatly exceeds that of the previously reported hydrazine-assisted water electrolyzers, offering a pathway for efficiently converting hazardous hydrazine into molecular hydrogen.

5.
Nat Nanotechnol ; 18(4): 357-364, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36702955

RESUMEN

The success of the lead halide perovskites in diverse optoelectronics has motivated considerable interest in their fundamental photocarrier dynamics. Here we report the discovery of photocarrier-induced persistent structural polarization and local ferroelectricity in lead halide perovskites. Photoconductance studies of thin-film single-crystal CsPbBr3 at 10 K reveal long-lasting persistent photoconductance with an ultralong photocarrier lifetime beyond 106 s. X-ray diffraction studies reveal that photocarrier-induced structural polarization is present up to a critical freezing temperature. Photocapacitance studies at cryogenic temperatures further demonstrate a systematic local phase transition from linear dielectric to paraelectric and relaxor ferroelectric under increasing illumination. Our theoretical investigations highlight the critical role of photocarrier-phonon coupling and large polaron formation in driving the local relaxor ferroelectric phase transition. Our findings show that this photocarrier-induced persistent structural polarization enables the formation of ferroelectric nanodomains at low temperature, which suppress carrier recombination and offer the possibility of exploring intriguing carrier-phonon interplay and the rich polaron photophysics.

6.
Nature ; 606(7916): 902-908, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35768590

RESUMEN

The discovery of chiral-induced spin selectivity (CISS) opens up the possibility to manipulate spin orientation without external magnetic fields and enables new spintronic device designs1-4. Although many approaches have been explored for introducing CISS into solid-state materials and devices, the resulting systems so far are often plagued by high inhomogeneity, low spin selectivity or limited stability, and have difficulties in forming robust spintronic devices5-8. Here we report a new class of chiral molecular intercalation superlattices (CMIS) as a robust solid-state chiral material platform for exploring CISS. The CMIS were prepared by intercalating layered two-dimensional atomic crystals (2DACs) (such as TaS2 and TiS2) with selected chiral molecules (such as R-α-methylbenzylamine and S-α-methylbenzylamine). The X-ray diffraction and transmission electron microscopy studies demonstrate highly ordered superlattice structures with alternating crystalline atomic layers and self-assembled chiral molecular layers. Circular dichroism studies show clear chirality-dependent signals between right-handed (R-) and left-handed (S-) CMIS. Furthermore, by using the resulting CMIS as the spin-filtering layer, we create spin-selective tunnelling junctions with a distinct chirality-dependent tunnelling current, achieving a tunnelling magnetoresistance ratio of more than 300 per cent and a spin polarization ratio of more than 60 per cent. With a large family of 2DACs of widely tunable electronic properties and a vast selection of chiral molecules of designable structural motifs, the CMIS define a rich family of artificial chiral materials for investigating the CISS effect and capturing its potential for new spintronic devices.

7.
Natl Sci Rev ; 9(5): nwab166, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35591915

RESUMEN

This perspective explores the development of van der Waals superlattices, which are manipulated and constructed at atomic thick level, and points out potential applications and possible future directions of this new class of materials.

8.
Science ; 375(6583): 852-859, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35201882

RESUMEN

The conformal integration of electronic systems with irregular, soft objects is essential for many emerging technologies. We report the design of van der Waals thin films consisting of staggered two-dimensional nanosheets with bond-free van der Waals interfaces. The films feature sliding and rotation degrees of freedom among the staggered nanosheets to ensure mechanical stretchability and malleability, as well as a percolating network of nanochannels to endow permeability and breathability. With an excellent mechanical match to soft biological tissues, the freestanding films can naturally adapt to local surface topographies and seamlessly merge with living organisms with highly conformal interfaces, rendering living organisms with electronic functions, including leaf-gate and skin-gate transistors. On-skin transistors allow high-fidelity monitoring and local amplification of skin potentials and electrophysiological signals.

9.
Adv Mater ; 33(25): e2004557, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33984164

RESUMEN

2D layered materials typically feature strong in-plane covalent chemical bonding within each atomic layer and weak out-of-plane van der Waals (vdW) interactions between adjacent layers. The non-bonding nature between neighboring layers naturally results in a vdW gap, in which various foreign species may be inserted without breaking the in-plane covalent bonds. By tailoring the composition, size, structure, and electronic properties of the intercalated guest species and the hosting layered materials, an expansive family of layered intercalation materials may be produced with highly variable compositional and structural features as well as widely tunable physical/chemical properties, invoking unprecedented opportunities in fundamental studies of property modulation and potential applications in diverse technologies, including electronics, optics, superconductors, thermoelectrics, catalysis, and energy storage. Here, the principles and protocols for various intercalation methods, including wet chemical intercalation, gas-phase intercalation, electrochemical intercalation, and ion-exchange intercalation, are comprehensively reviewed and how the intercalated species alter the crystal structure and the interlayer coupling of the host 2D layered materials, introducing unusual physical and chemical properties and enabling devices with superior performance or unique functions, is discussed. To conclude, a brief summary on future research opportunities and emerging challenges in the layered intercalation materials is given.

10.
ACS Nano ; 13(5): 5541-5548, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31034773

RESUMEN

Graphene exhibits properties of atomic thickness, high transparency, and high carrier mobility, which is highly desirable for a flexible transparent conductive material. However, the electronic properties of large-area chemical vapor deposition grown graphene film suffer from insulated polymer contaminations introduced by the transfer process and the easily cracked nature. Here, we report a preparation method of a transfer-medium-free large-area nanofiber-reinforced graphene (a-PAN/G) film simply by annealing the electrostatically spun polyacrylonitrile (PAN) nanofibers on the graphene film. The film could be free-standing on water and suspended in air with high transparency and enhanced electrical and mechanical properties compared to that of a monolayer graphene film. The flexible transparent a-PAN/G films were demonstrated as active materials for sensitive pressure sensors. The obtained pressure sensors demonstrate high sensitivity (44.5 kPa-1 within 1.2 kPa), low operating voltage (0.01-0.5 V), and excellent stability for 5500 loading-unloading cycles, revealing promising potential applications in wearable electronics.

11.
Chem Soc Rev ; 47(9): 3152-3188, 2018 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-29412208

RESUMEN

Wearable energy sources are in urgent demand due to the rapid development of wearable electronics. Besides flexibility and ultrathin thickness, emerging 2D materials present certain extraordinary properties that surpass the properties of conventional materials, which make them advantageous for high-performance wearable energy sources. Here, we provide a comprehensive review of recent advances in 2D material based wearable energy sources including wearable batteries, supercapacitors, and different types of energy harvesters. The crucial roles of 2D materials in the wearable energy sources are highlighted. Based on the current progress, the existing challenges and future prospects are outlined and discussed.

12.
Adv Mater ; 29(47)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29076181

RESUMEN

Aluminum (Al) foil, as the most accepted cathode current collector for lithium-ion batteries (LIBs), is susceptible to local anodic corrosions during long-term operations. Such corrosions could lead to the deterioration or even premature failure of the batteries and are generally believed to be a bottleneck for next-generation 5 V LIBs. Here, it is demonstrated that Al foil armored by conformal graphene coating exhibits significantly reinforced anodic corrosion resistance in both LiPF6 and lithium bis(trifluoromethanesulphonyl) imide (LiTFSI) based electrolytes. Moreover, LiMn2 O4 cells using graphene-armored Al foil as current collectors (LMO/GA) demonstrate enhanced electrochemical performance in comparison with those using pristine Al foil (LMO/PA). The long-term discharge capacity retention of LMO/GA cell after ≈950 h straight operations at low rate (0.5 C) reaches up to 91%, remarkably superior to LMO/PA cell (75%). The self-discharge propensity of LMO/GA is clearly relieved and the rate/power performance is also improved with graphene mediations. This work not only contributes to the long-term stable operations of LIBs but also might catalyze the deployment of 5 V LIBs in the future.

13.
Adv Mater ; 29(38)2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28833544

RESUMEN

Efficient solar-thermal energy conversion is essential for the harvesting and transformation of abundant solar energy, leading to the exploration and design of efficient solar-thermal materials. Carbon-based materials, especially graphene, have the advantages of broadband absorption and excellent photothermal properties, and hold promise for solar-thermal energy conversion. However, to date, graphene-based solar-thermal materials with superior omnidirectional light harvesting performances remain elusive. Herein, hierarchical graphene foam (h-G foam) with continuous porosity grown via plasma-enhanced chemical vapor deposition is reported, showing dramatic enhancement of broadband and omnidirectional absorption of sunlight, which thereby can enable a considerable elevation of temperature. Used as a heating material, the external solar-thermal energy conversion efficiency of the h-G foam impressively reaches up to ≈93.4%, and the solar-vapor conversion efficiency exceeds 90% for seawater desalination with high endurance.

14.
Nano Lett ; 16(12): 7731-7738, 2016 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-27802387

RESUMEN

Magnetic resonance imaging (MRI) compatible neural electrodes are important for combining high-resolution electrophysiological measurements with more global MRI mapping of brain activity, which is critical for fundamental neuroscience studies, as well as clinical evaluation and monitoring. Copper is a favorable material to use in MRI because it has magnetic susceptibility close to water and tissues. However, the cytotoxicity of copper precludes its direct implantation for neural recording. Here, we overcome this limitation by developing a graphene encapsulated copper (G-Cu) microelectrode. The toxicity of copper is largely eliminated, as evidenced by the in vitro cell tests and in vivo histology studies. Local field potentials and single-unit spikes were recorded from rodent brains with the G-Cu microelectrodes. Notably, the G-Cu microelectrodes show no image artifacts in a 7.0 T MRI scanner, indicating minimal magnetic field distortion in their vicinity. This high MRI compatibility of our G-Cu probes would open up new opportunities for fundamental brain activity studies and clinical applications requiring continuous MRI and electrophysiological recordings.

15.
Adv Mater ; 28(40): 8968-8974, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27562642

RESUMEN

Wafer-sized single-crystalline Cu (100) surface can be readily achieved on stacked polycrystalline Cu foils via simple oxygen chemisorption-induced reconstruction, enabling fast growth of large-scale millimeter-sized single-crystalline graphene arrays under molecular flow. The maximum growth rate can reach 300 µm min-1 , several orders of magnitude higher than previously reported values for millimeter-sized single-crystalline graphene growth on Cu foils.

16.
ACS Nano ; 10(2): 2922-9, 2016 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-26832229

RESUMEN

The controlled growth of high-quality graphene on a large scale is of central importance for applications in electronics and optoelectronics. To minimize the adverse impacts of grain boundaries in large-area polycrystalline graphene, the synthesis of large single crystals of monolayer graphene is one of the key challenges for graphene production. Here, we develop a facile surface-engineering method to grow large single-crystalline monolayer graphene by the passivation of the active sites and the control of graphene nucleation on copper surface using the melamine pretreatment. Centimeter-sized hexagonal single-crystal graphene domains were successfully grown, which exhibit ultrahigh carrier mobilities exceeding 25,000 cm(2) V(-1) s(-1) and quantum Hall effects on SiO2 substrates. The underlying mechanism of melamine pretreatments were systematically investigated through elemental analyses of copper surface in the growth process of large single-crystals. This present work provides a surface design of a catalytic substrate for the controlled growth of large-area graphene single crystals.

17.
ACS Appl Mater Interfaces ; 8(1): 1025-32, 2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26691674

RESUMEN

A quartz fiber based 3D monolithic materials was fabricated, which combines ultrahigh thermostability, remote controllability, mechanical flexibility, high water/oil selectivity, high processing capacity, and regeneration ability. This material exhibited great potential in water remediation, such as large absorption capacity (50- to 172-fold weight gain) toward oil standing in front of all magnetic sorbents and remarkable oil/water separation performance.

18.
Int J Gynaecol Obstet ; 131(3): 277-80, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26391672

RESUMEN

OBJECTIVE: To investigate the distribution of HPV subtypes and analyze variation in infection trends during a 6-year period in Sichuan Province, China. METHODS: A cross-sectional observational study was conducted at a center in Chengdu between January 1, 2009, and December 31, 2014. Patients with at least one type of cervical disease confirmed by histology and cytology were eligible for inclusion. Cervical specimens were tested for the presence of high-risk and low-risk HPV subtypes by reverse membrane hybridization. RESULTS: Among 10 682 participants, 3370 women (31.5%) were infected with HPV. The most frequently detected high-risk genotypes were HPV16 (n=791; 27.1%), HPV58 (n=476; 16.3%), HPV33 (n=273; 9.4%), HPV52 (n=244; 8.4%), and HPV18 (n=201; 6.9%). The most frequently detected low-risk genotype was HPV6 (n=703; 40.8%). The detection rates of HPV33 (from 7.9% to 10.2%) and HPV58 (from 14.0% to 16.7%) increased over the 6-year period, whereas those of HPV16 (from 32.3% to 24.9%) and HPV18 (from 10.0% to 6.2%) decreased. The prevalence of HPV infection was highest among women aged 21-25 years (χ(2)=191.189; P<0.001). CONCLUSION: HPV58 and HPV33 were the most prevalent subtypes in Sichuan. Changes in the prevalences of infection with different HPV subtypes have been identified.


Asunto(s)
Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Enfermedades del Cuello del Útero/epidemiología , Adulto , China/epidemiología , Estudios Transversales , Femenino , Genotipo , Humanos , Persona de Mediana Edad , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Prevalencia , Enfermedades del Cuello del Útero/virología , Adulto Joven
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 32(2): 269-73, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-25863102

RESUMEN

OBJECTIVE: To assess the association of single nucleotide polymorphisms (SNPs) of ubiquitin-specific protease 8 gene (USP8) with male infertility among ethnic Han Chinese from Sichuan. METHODS: A total of 316 infertile males were recruited (case group), which included 72 severe oligozoospermic (SO) cases and 244 non-obstructive azoospermic (NOA) cases. The control group consisted of 149 fertile males. The genotypes of 4 SNPs (rs2241769, rs11857513, rs7174015 and rs3743044) were determined with a Sequenom MassArray technique. The frequencies of genotype, allele and haploptye were analyzed. RESULTS: No significant difference was detected in the allelic or genotypic frequencies of the 4 SNPs between the two groups (P>0.05). Based on linkage disequilibrium analysis and haplotype construction, the frequency distribution of haplotype CAAG showed a significant difference between non-obstructive azoospermic patients and the controls (P=0.021). CONCLUSION: The 4 SNPs (rs2241769, rs11857513, rs7174015 and rs3743044) of USP8 gene may not be associated with male infertility in ethnic Hans from Sichuan. While the haplotype CAAG may be a down-regulating factor for the risk of NOA.


Asunto(s)
Pueblo Asiatico/genética , Endopeptidasas/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Infertilidad Masculina/genética , Polimorfismo de Nucleótido Simple , Ubiquitina Tiolesterasa/genética , Adulto , Pueblo Asiatico/etnología , Azoospermia/genética , Secuencia de Bases , Estudios de Casos y Controles , China/etnología , Predisposición Genética a la Enfermedad/etnología , Genotipo , Humanos , Infertilidad Masculina/etnología , Masculino , Datos de Secuencia Molecular
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