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1.
Science ; 383(6678): 86-93, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38175897

RESUMEN

The metal-halide ionic octahedron is the optoelectronic unit for halide perovskites, and a crown ether-assisted supramolecular assembly approach can pack various ionic octahedra into tunable symmetries. In this work, we demonstrate near-unity photoluminescence quantum yield (PLQY) blue and green emission with the supramolecular assembly of hafnium (Hf) and zirconium (Zr) halide octahedral clusters. (18C6@K)2HfBr6 powders showed blue emission with a near-unity PLQY (96.2%), and green emission was also achieved with (18C6@K)2ZrCl4Br2 powders at a PLQY of 82.7%. These highly emissive powders feature facile low-temperature solution-based synthesis conditions and maintain high PLQY in solution-processable semiconductor inks under ambient conditions, and they were used in thin-film displays and emissive three-dimensional-printed architectures that exhibited high spatial resolution.

2.
Nano Lett ; 23(24): 11469-11476, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38060980

RESUMEN

Energy funneling is a phenomenon that has been exploited in optoelectronic devices based on low-dimensional materials to improve their performance. Here, we introduce a new class of two-dimensional semiconductor, characterized by multiple regions of varying thickness in a single confined nanostructure with homogeneous composition. This "noninteger 2D semiconductor" was prepared via the structural transformation of two-octahedron-layer-thick (n = 2) 2D cesium lead bromide perovskite nanosheets; it consisted of a central n = 2 region surrounded by edge-lying n = 3 regions, as imaged by electron microscopy. Thicker noninteger 2D CsPbBr3 nanostructures were obtained as well. These noninteger 2D perovskites formed a laterally coupled quantum well band alignment with virtually no strain at the interface and no dielectric barrier, across which unprecedented intramaterial funneling of the photoexcitation energy was observed from the thin to the thick regions using time-resolved absorption and photoluminescence spectroscopy.

3.
Nature ; 621(7978): 282-288, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37587347

RESUMEN

Although high-entropy materials are excellent candidates for a range of functional materials, their formation traditionally requires high-temperature synthetic procedures of over 1,000 °C and complex processing techniques such as hot rolling1-5. One route to address the extreme synthetic requirements for high-entropy materials should involve the design of crystal structures with ionic bonding networks and low cohesive energies. Here we develop room-temperature-solution (20 °C) and low-temperature-solution (80 °C) synthesis procedures for a new class of metal halide perovskite high-entropy semiconductor (HES) single crystals. Due to the soft, ionic lattice nature of metal halide perovskites, these HES single crystals are designed on the cubic Cs2MCl6 (M=Zr4+, Sn4+, Te4+, Hf4+, Re4+, Os4+, Ir4+ or Pt4+) vacancy-ordered double-perovskite structure from the self-assembly of stabilized complexes in multi-element inks, namely free Cs+ cations and five or six different isolated [MCl6]2- anionic octahedral molecules well-mixed in strong hydrochloric acid. The resulting single-phase single crystals span two HES families of five and six elements occupying the M-site as a random alloy in near-equimolar ratios, with the overall Cs2MCl6 crystal structure and stoichiometry maintained. The incorporation of various [MCl6]2- octahedral molecular orbitals disordered across high-entropy five- and six-element Cs2MCl6 single crystals produces complex vibrational and electronic structures with energy transfer interactions between the confined exciton states of the five or six different isolated octahedral molecules.

4.
Parasit Vectors ; 16(1): 195, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37296439

RESUMEN

BACKGROUND: Babesiosis is a globally growing tick-borne disease in humans. Severe babesiosis caused by Babesia divergens has been reported in two patients from Asturias (Northwestern Spain), suggesting an undetected risk for the disease. To analyze this risk, we retrospectively evaluated the seroprevalence of babesiosis in the Asturian population from 2015 through 2017, a period covering the intermediate years in which these two severe cases occurred. METHODS: Indirect fluorescent assay (IFA) and Western blot (WB) were performed to detect B. divergens IgG antibodies in 120 serum samples from Asturian patients infected with the tick-transmitted spirochete Borrelia burgdorferi sensu lato, a condition that indicates exposure to tick bites. RESULTS: This retrospective study confirmed a B. divergens seroprevalence rate of 39.2% according to IFA results. B. divergens incidence was 7.14 cases/100,000 population, exceeding previously reported seroprevalence rates. No differences in epidemiology and risk factors were found between patients infected solely with B. burgdorferi s.l. and those infected with B. burgdorferi s.l. and with IgG antibodies against B. divergens. This last group of patients lived in Central Asturias, had a milder clinical course and, according to WB results, developed different humoral responses against B. divergens. CONCLUSIONS: Babesia divergens parasites have circulated for several years in Asturias. Epidemiological evidence of babesiosis makes Asturias an emerging risk area for this zoonosis. Human babesiosis could also be relevant in other Spanish and European regions affected by borreliosis. Hence, the potential risk of babesiosis on human health in Asturias and other European forest regions needs to be addressed by the health authorities.


Asunto(s)
Babesia , Babesiosis , Animales , Humanos , Babesiosis/diagnóstico , Babesiosis/epidemiología , Babesiosis/parasitología , Estudios Retrospectivos , España/epidemiología , Estudios Seroepidemiológicos , Inmunoglobulina G
5.
J Am Chem Soc ; 144(27): 12450-12458, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35771005

RESUMEN

The structural diversity and tunable optoelectronic properties of halide perovskites originate from the rich chemistry of the metal halide ionic octahedron [MX6]n- (M = Pb2+, Sb3+, Te4+, Sn4+, Pt4+, etc.; X = Cl-, Br-, and I-). The properties of the extended perovskite solids are dictated by the assembly, connectivity, and interaction of these octahedra within the lattice environment. Hence, the ability to manipulate and control the assembly of the octahedral building blocks is paramount for constructing new perovskite materials. Here, we propose a systematic supramolecular strategy for the assembly of [MX6]n- octahedra into a solid extended network. Interaction of alkali metal-bound crown ethers with the [M(IV)X6]2- octahedron resulted in a structurally and optoelectronically tunable "dumbbell" structural unit in solution. Single crystals with diverse packing geometries and symmetries will form as the solid assembly of this new supramolecular building block. This supramolecular assembly route introduces a new general strategy for designing halide perovskite structures with potentially new optoelectronic properties.

6.
Nano Lett ; 21(20): 8856-8862, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34612654

RESUMEN

Traditional covalent semiconductors require complex processing methods for device fabrication due to their high cohesive energies. Here, we develop a stable, ligand-free perovskite semiconductor ink that can be used to make patterned semiconductor-based optoelectronics in one step. The perovskite ink is formed via the dissolution of crystals of vacancy-ordered double perovskite Cs2TeX6 (X = Cl-, Br-, I-) in polar aprotic solvents, leading to the stabilization of isolated [TeX6]2- octahedral anions and free Cs+ cations without the presence of ligands. The stabilization of the fundamental perovskite ionic octahedral building blocks in solution creates multifunctional inks with the ability to reversibly transform between the liquid ink and the solid-state perovskite crystalline system in air within minutes. These easily processable inks can be patterned onto various materials via dropcasting, spraying or painting, and stamping, highlighting the crucial role of solvated octahedral complexes toward the rapid formation of phase-pure perovskite structures in ambient conditions.

7.
Nano Lett ; 21(12): 5415-5421, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34120442

RESUMEN

The metal halide ionic octahedron, [MX6] (M = metal cation, X = halide anion), is considered to be the fundamental building block and functional unit of metal halide perovskites. By representing the metal halide ionic octahedron in halide perovskites as a super ion/atom, the halide perovskite can be described as an extended ionic octahedron network (ION) charge balanced by selected cations. This new perspective of halide perovskites based on ION enables the prediction of different packing and connectivity of the metal halide octahedra based on different solid-state lattices. In this work, a new halide perovskite Cs8Au3.5In1.5Cl23 was discovered on the basis of a BaTiO3-lattice ION {[InCl6][AuCl5][Au/InCl4]3}8-, which is assembled from three different ionic octahedra [InCl6], [AuCl6], and [Au/InCl6] and balanced by positively charged Cs cations. The success of this ION design concept in the discovery of Cs8Au3.5In1.5Cl23 opens up a new venue for the rational design of new halide perovskite materials.

8.
Proc Natl Acad Sci U S A ; 116(47): 23404-23409, 2019 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-31685626

RESUMEN

Phase transitions in halide perovskites triggered by external stimuli generate significantly different material properties, providing a great opportunity for broad applications. Here, we demonstrate an In-based, charge-ordered (In+/In3+) inorganic halide perovskite with the composition of Cs2In(I)In(III)Cl6 in which a pressure-driven semiconductor-to-metal phase transition exists. The single crystals, synthesized via a solid-state reaction method, crystallize in a distorted perovskite structure with space group I4/m with a = 17.2604(12) Å, c = 11.0113(16) Å if both the strong reflections and superstructures are considered. The supercell was further confirmed by rotation electron diffraction measurement. The pressure-induced semiconductor-to-metal phase transition was demonstrated by high-pressure Raman and absorbance spectroscopies and was consistent with theoretical modeling. This type of charge-ordered inorganic halide perovskite with a pressure-induced semiconductor-to-metal phase transition may inspire a range of potential applications.

9.
BMC Cancer ; 14: 855, 2014 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-25413006

RESUMEN

BACKGROUND: Pulmonary neuroendocrine tumors (Pulmonary NETs) include a wide spectrum of tumors, from the low-grade typical carcinoid (TC) and the intermediate-grade atypical carcinoid (AC), to the high-grade large-cell neuroendocrine carcinoma (LCNEC) and the small-cell carcinoma (SCLC). Epithelial Mesenchymal Transition (EMT) is a process initially recognised during several critical stages of embryonic development, which has more recently been implicated in promoting carcinoma invasion and metastasis. The initial stage of the EMT process begins with the deregulation of adhesion molecules, such as E-cadherin, due to transcriptional repression carried out by factors such as Snail family members, Twist and Foxc2. METHODS: Immunohistochemistry for EMT markers and E-cadherin/ ß-catenin complex in 134 patients with pulmonary NETs between 1990 - 2009. Analysis of potential associations with clinicopathological variables and survival. RESULTS: Pulmonary NETs of high malignant potential (LCNEC and SCLC) had reduced expression of the adhesion molecules and high level expression of transcriptional repressors (Snail1, Snail2, Twist and Foxc2). Snail high expression levels and the loss of E-cadherin/ß-catenin complex integrity had the strongest negative effect on the five-year survival rates. E-cadherin/ß-catenin complex integrity loss independently predicted lymph node involvement and helped in Atypical Carcinoid (AC) vs Typical Carcinoid (TC) differential diagnosis. Importantly, among the TC group, the loss of E-cadherin/ß-catenin complex integrity identified patients with an adverse clinical course despite favourable clinicopathological features. CONCLUSION: The immunohistochemical determination of E-cadherin/ß-catenin complex integrity loss and EMT markers in the clinical setting might be a potential useful diagnostic and prognostic tool especially among the TC patients.


Asunto(s)
Biomarcadores de Tumor , Transición Epitelial-Mesenquimal , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Tumores Neuroendocrinos/metabolismo , Tumores Neuroendocrinos/patología , Adulto , Anciano , Terapia Combinada , Diagnóstico Diferencial , Femenino , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/terapia , Metástasis Linfática , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/mortalidad , Tumores Neuroendocrinos/terapia , Pronóstico , Factores de Riesgo , Carga Tumoral
10.
J Adv Nurs ; 70(12): 2810-20, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24773512

RESUMEN

AIMS: To investigate behavioural risk factors and self-efficacy among women diagnosed with breast cancer. BACKGROUND: The appearance of new tumours in breast cancer survivors is influenced by risk behaviours. Knowing their prevalence and women's perceived ability to adopt a healthy lifestyle would allow designing educational interventions aimed at modifying these behaviours. DESIGN: An observational cross-sectional study of women diagnosed with breast cancer. METHODS: The study was carried out in Asturias (Spain). A total of 2407 breast cancer patients diagnosed between 1998-2008 were selected and 492 women agreed to participate. Self-reported data on risk factors self-efficacy were gathered through a telephone interview based on the European Code against Cancer conducted between February-June 2010. RESULTS: A total of 16·1% of women in this study were regular smokers, 5% drank alcohol excessively, 49% were overweight, 54% reported a lower level of physical activity than recommended and 7·5% did not use sun protection. The Total Cancer Behavioural Risk indicator was calculated by adding up the results of all modifiable risks contained in the European Code against Cancer, with an average score of 21·6 in a scale from 0-78 points (0 = null cancer risk, 78 = maximum cancer risk). Self-efficacy levels were very high among our participants. CONCLUSION: The results suggest that there is a need to design programmes to promote a healthy lifestyle among women diagnosed with breast cancer. Nurses have an important role to play in planning and implementing these programmes, using the most efficient educational techniques.


Asunto(s)
Terapia Conductista/educación , Neoplasias de la Mama/enfermería , Neoplasias de la Mama/psicología , Recurrencia Local de Neoplasia/psicología , Rol de la Enfermera , Educación del Paciente como Asunto , Autoeficacia , Adulto , Anciano , Estudios Transversales , Femenino , Promoción de la Salud , Humanos , Persona de Mediana Edad , Factores de Riesgo , Autoinforme , España , Sobrevivientes/psicología
11.
Eur J Cancer Prev ; 17(5): 406-13, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18714181

RESUMEN

Breast cancer (BC) survivors have an increased risk of developing second primary cancer (SPC). The aim of this study was to detect and compare SPC predictors linked to the host, the first BC and its treatment. Two hundred and seventeen patients with a nonbreast SPC and 465 matched controls, nested in the cohort of BC patients diagnosed in a Spanish region between 1975 and 2003, were involved in a case-control study. The Tumour Registry database provided information about the host, BC and its treatment factors. Their contribution to the risk of developing SPC was measured by means of a conditional logistic regression. After controlling for differences between cases and controls at baseline, obesity [odds ratio (OR): 7.48; 95% confidence interval (CI): 1.25-44.88], smoking (OR: 3.16; 95% CI: 1.23-8.15), high blood pressure (OR: 1.68; 95% CI: 1.04-2.71) and having first-degree relatives suffering from cancer (OR: 1.69; 95% CI: 1.05-2.72) were the best SPC predictors. The risk of SPC increases by 1% per month of survival from BC (OR: 1.01; 95% CI: 1.007-1.012), while having metastases (OR: 0.23; 95% CI: 0.14-0.37) and being premenopausal at diagnosis of the BC (OR: 0.44; 95% CI: 0.247-0.792) diminish the risk, probably decreasing survival. The treatments were the regression model's worst predictors. Controlling modifiable factors linked to lifestyle such as obesity and smoking is essential to prevent SPC in survivors of BC. Health education to remove persistent risk factors should be included in the treatment protocol of BC patients, because they are important predictors of SPC.


Asunto(s)
Neoplasias de la Mama , Neoplasias Primarias Secundarias/etiología , Sobrevivientes , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma Endometrioide/epidemiología , Carcinoma Endometrioide/etiología , Carcinoma Endometrioide/mortalidad , Estudios de Casos y Controles , Neoplasias Endometriales/epidemiología , Neoplasias Endometriales/etiología , Neoplasias Endometriales/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/mortalidad , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/etiología , Neoplasias Ováricas/mortalidad , Factores de Riesgo , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/mortalidad , Análisis de Supervivencia , Sobrevivientes/estadística & datos numéricos
12.
Dermatol Surg ; 30(4 Pt 1): 566-9, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15056154

RESUMEN

BACKGROUND: The detection of tumor-associated glycoprotein-72 in the serum of patients with carcinomas, basically of the colon, has proved to be of great use in the follow-up of these gastrointestinal adenocarcinomas. RESULTS: We report the case of a male patient presenting adenopathies in the right axilla. The histologic study of an adjacent skin tumor enabled the diagnosis of a cutaneous apocrine carcinoma. Among the studies made, the increase in the serum antibody CA72.4 can be highlighted. The tumor marker was negative after the extirpation of the skin tumor and the axillary adenopathies. CONCLUSION: To our best knowledge, this is the first case in which a tumor serum marker is associated with a cutaneous apocrine carcinoma, a fact that should be confirmed with further patients. Its use in the monitoring of this infrequent skin neoplasia is also noteworthy.


Asunto(s)
Antígenos de Neoplasias/sangre , Glándulas Apocrinas/patología , Biomarcadores de Tumor/sangre , Carcinoma/patología , Glicoproteínas/sangre , Neoplasias de las Glándulas Sudoríparas/patología , Anciano , Axila , Carcinoma/sangre , Carcinoma/complicaciones , Humanos , Enfermedades Linfáticas/sangre , Enfermedades Linfáticas/etiología , Enfermedades Linfáticas/patología , Metástasis Linfática , Masculino , Sensibilidad y Especificidad , Neoplasias de las Glándulas Sudoríparas/sangre , Neoplasias de las Glándulas Sudoríparas/complicaciones
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