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1.
Angew Chem Int Ed Engl ; 62(41): e202309398, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37624069

RESUMEN

Photovoltaic technology with low weight, high specific power in cold environments, and compatibility with flexible fabrication is highly desired for near-space vehicles and polar region applications. Herein, we demonstrate efficient low-temperature flexible perovskite solar cells by improving the interfacial contact between electron-transport layer (ETL) and perovskite layer. We find that the adsorbed oxygen active sites and oxygen vacancies of flexible tin oxide (SnO2 ) ETL layer can be effectively decreased by incorporating a trace amount of titanium tetrachloride (TiCl4 ). The effective defects elimination at the interfacial increases the electron mobility of flexible SnO2 layer, regulates band alignment at the perovskite/SnO2 interface, induces larger perovskite crystal growth, and improves charge collection efficiency in a complete solar cell. Correspondingly, the improved interfacial contact transforms into high-performance solar cells under one-sun illumination (AM 1.5G) with efficiencies up to 23.7 % at 218 K, which might open up a new era of application of this emerging flexible photovoltaic technology to low-temperature environments such as near-space and polar regions.

2.
ACS Appl Mater Interfaces ; 16(13): 16300-16308, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38513050

RESUMEN

Halide perovskites are emerging as promising materials for X-ray detection owing to their compatibility with flexible fabrication, cost-effective solution processing, and exceptional carrier transport behaviors. However, the challenge of removing lead from high-performing perovskites, crucial for wearable electronics, while retaining their superior performance, persists. Here, we present for the first time a highly sensitive and robust flexible X-ray detector utilizing a biocompatible, metal-free perovskite, MDABCO-NH4I3 (MDABCO = methyl-N'-diazabicyclo[2.2.2]octonium). This wearable X-ray detector, based on a MDABCO-NH4I3 thick membrane, exhibits remarkable properties including a large resistivity of 1.13 × 1011 Ω cm, a high mobility-lifetime product (µ-τ) of 1.64 × 10-4 cm2 V-1, and spin Seebeck effect coefficient of 1.9 nV K-1. We achieve a high sensitivity of 6521.6 ± 700 µC Gyair-1 cm-2 and a low detection limit of 77 nGyair s-1, ranking among the highest for biocompatible X-ray detectors. Additionally, the device exhibits effective X-ray imaging at a low dose rate of 1.87 µGyair s-1, which is approximately one-third of the dose rate used in regular medical diagnostics. Crucially, both the MDABCO-NH4I3 thick membrane and the device showcase excellent mechanical robustness. These attributes render the flexible MDABCO-NH4I3 thick membranes highly competitive for next-generation, high-performance, wearable X-ray detection applications.

3.
Adv Mater ; 36(24): e2311562, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38507724

RESUMEN

A robust perovskite-buried interface is pivotal for achieving high-performance flexible indoor photovoltaics as it significantly influences charge transport and extraction efficiency. Herein, a molecular bridge strategy is introduced utilizing sodium 2-cyanoacetate (SZC) additive at the perovskite-buried interface to simultaneously achieve in situ passivation of interfacial defects and bottom-up crystallization modulation, resulting in high-performance flexible indoor photovoltaic applications. Supported by both theoretical calculations and experimental evidences, it illustrates how SZCs serve as molecular bridges, establishing robust bonds between SnO2 transport layer and perovskite, mitigating oxygen vacancy defects and under-coordinated Pb defects at interface during flexible fabrication. This, in turn, enhances interfacial energy level alignment and facilitates efficient carrier transport. Moreover, this in situ investigation of perovskite crystallization dynamics reveals bottom-up crystallization modulation, extending perovskite growth at the buried interface and influencing subsequent surface recrystallization. This results in larger crystalline grains and improved lattice strain of the perovskite during flexible fabrication. Finally, the optimized flexible solar cells achieve an impressive efficiency exceeding 41% at 1000 lux, with a fill factor as high as 84.32%. The concept of the molecular bridge represents a significant advancement in enhancing the performance of perovskite-based flexible indoor photovoltaics for the upcoming era of Internet of Things (IoT).

4.
Adv Mater ; 36(23): e2312014, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38380583

RESUMEN

Perovskite photovoltaics have emerged as the most promising candidates for next-generation light-to-electricity technology. However, their practical application still suffers from energy loss induced by intrinsic defects within the perovskite lattice. Here, a refined defect passivation in perovskite films is designed, which shows a multi-interaction mechanism between the perovskite and passivator. Interestingly, a shift of molecular bonding is observed upon cooling down the film, leading to a stronger passivation of iodine/formamidine vacancies. Such mechanism on device under low-light and low-temperature conditions is further leveraged and a record efficiency over 45% with durable ambient stability (T90 > 4000 h) is obtained. The pioneer application of perovskite solar cells in above dual extreme conditions in this work reveals the key principles of designing functional groups for the passivators, and also demonstrates the capability of perovskites for diverse terrestrial energy conversion applications in demanding environments such as polar regions and outer space.

5.
Adv Mater ; 35(51): e2303384, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37572021

RESUMEN

Upscalable printing of high-performance and stable perovskite solar cells (PSCs) is highly desired for commercialization. However, the efficiencies of printed PSCs lag behind those of their lab-scale spin-coated counterparts owing to the lack of systematic understanding and control over perovskite crystallization dynamics. Here, the controlled crystallization dynamics achieved using an additive 1-butylpyridine tetrafluoroborate (BPyBF4 ) for high-quality ambient printed α-formamidinium lead triiodide (FAPbI3 ) perovskite films are reported. Using in situ grazing-incidence wide-angle X-ray scattering and optical diagnostics, the spontaneous formation of α-FAPbI3 from precursors during printing without the involvement of  Î´-FAPbI3 is demonstrated. The addition of BPyBF4 delays the crystallization onset of α-FAPbI3 , enhances the conversion from sol-gel to perovskite, and reduces stacking defects during printing. Therefore, the altered crystallization results in fewer voids, larger grains, and less trap-induced recombination loss within printed films. The printed PSCs yield high power conversion efficiencies of 23.50% and 21.60% for a 0.09 cm-2 area device and a 5 cm × 5 cm-area module, respectively. Improved device stability is further demonstrated, i.e., approximately 94% of the initial efficiency is retained for over 2400 h under ambient conditions without encapsulation. This study provides an effective crystallization control method for the ambient printing manufacture of large-area high-performance PSCs.

6.
Yi Chuan ; 31(3): 285-9, 2009 Mar.
Artículo en Zh | MEDLINE | ID: mdl-19273442

RESUMEN

The polymorphism distributions of 14 microsatellite loci were detected using the Bovine Paternity PCR Typing Kit (including 11 X-STR) and 3 selected Y-STR microsatellite DNA markers. The genetic diversity were evaluated, and the feasibility of the application to individual identification and paternity testing were discussed. The results showed that all the 14 microsatellite loci had genetic polymorphisms in bulls, and the polymorphism information content (PIC) in loci MCM158 was the biggest (0.888), while the ETH10 was the lowest (0.482). Power of discrimination (DP) value of the 14 STR loci ranged from 0.715 to 0.968. The Cumulate DP (CDP) was 99.99%, and the Cumulate PE (CPE) also reached 99.99%. These results indicate that the 14 microsatellites can be applied to the individual identification.


Asunto(s)
Dermatoglifia del ADN/métodos , Repeticiones de Microsatélite/genética , Animales , Bovinos , Cromosomas de los Mamíferos/genética , Variación Genética/genética , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo Genético/genética , Cromosoma Y/genética
7.
Yi Chuan ; 30(9): 1187-94, 2008 Sep.
Artículo en Zh | MEDLINE | ID: mdl-18779178

RESUMEN

The complete sequences of mitochondrial DNA D-loop of 140 individuals in 10 Chinese goat (Capra hiruc) breeds were analyzed by DNA sequencing technology. The results showed that the length of mtDNA D-loop in Chinese goats was 1 211-1 213 bp. There were 84 different haplotypes and 171 polymorphic sites. The mean nucleotide diversity (Pi) and haplotype diversity (Hd) were 0.02063+/+0.00225 and 0.988+/-0.003, respectively, and the average number of nucleotide differences (k) was 24.896. The results showed an abundant genetic diversity in domestic goats of China. The NJ tree indicated that there were two main branches in Chinese domestic goats, thereinto, one branch was clustered with Capra aegagrus, and Capra falconeri was clustered alone, which indicated that Capra aegagrus had more contribution to Chinese domestic goat breeds.


Asunto(s)
ADN Mitocondrial/genética , Cabras/genética , Mitocondrias/genética , Animales , Animales Domésticos/genética , China , ADN Mitocondrial/análisis , ADN Mitocondrial/química , Evolución Molecular , Variación Genética , Haplotipos , Conformación de Ácido Nucleico , Análisis de Secuencia de ADN
8.
Assay Drug Dev Technol ; 4(1): 37-48, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16506887

RESUMEN

Clinical treatment of neuropathic pain can be achieved with a number of different drugs, some of which interact with all members of the voltage-gated sodium channel (NaV1) family. However, block of central nervous system and cardiac NaV1 channels can cause dose-limiting side effects, preventing many patients from achieving adequate pain relief. Expression of the tetrodotoxin-resistant NaV1.8 subtype is restricted to small-diameter sensory neurons, and several lines of evidence indicate a role for NaV1.8 in pain processing. Given these features, NaV1.8 subtype-selective blockers are predicted to be efficacious in the treatment of neuropathic pain and to be associated with fewer adverse effects than currently available therapies. To facilitate the identification of NaV1.8-specific inhibitors, we stably expressed the human NaV1.8 channel together with the auxiliary human beta1 subunit (NaV beta1) in human embryonic kidney 293 cells. Heterologously expressed human NaV1.8/NaV beta1 channels display biophysical properties that are similar to those of tetrodotoxin-resistant channels present in mouse dorsal root ganglion neurons. A membrane potential, fluorescence resonance energy transfer-based functional assay on a fluorometric imaging plate reader (FLIPR-Tetra, Molecular Devices, Sunnyvale, CA) platform has been established. This highcapacity assay is sensitive to known state-dependent NaV1 modulators and can be used to identify novel and selective NaV1.8 inhibitors.


Asunto(s)
Potenciales de la Membrana/fisiología , Neuronas Aferentes/fisiología , Canales de Sodio/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , Cartilla de ADN , Electrofisiología/métodos , Transferencia Resonante de Energía de Fluorescencia/métodos , Humanos , Riñón , Modelos Moleculares , Datos de Secuencia Molecular , Canal de Sodio Activado por Voltaje NAV1.8 , Fragmentos de Péptidos/inmunología , Conformación Proteica , Conejos , Canales de Sodio/genética
9.
Cancer Med ; 4(1): 43-55, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25418975

RESUMEN

Epigenetic remodeling of cell adhesion genes is a common phenomenon in cancer invasion. This study aims to investigate global methylation of cell adhesion genes in cervical carcinogenesis and to apply them in early detection of cancer from cervical scraping. Genome-wide methylation array was performed on an investigation cohort, including 16 cervical intraepithelial neoplasia 3 (CIN3) and 20 cervical cancers (CA) versus 12 each of normal, inflammation and CIN1 as controls. Twelve members of clustered proto-cadherin (PCDH) genes were collectively methylated and silenced, which were validated in cancer cells of the cervix, endometrium, liver, head and neck, breast, and lung. In an independent cohort including 107 controls, 66 CIN1, 85 CIN2/3, and 38 CA, methylated PCDHA4 and PCDHA13 were detected in 2.8%, 24.2%, 52.9%, and 84.2% (P < 10(-25) ), and 2.8%, 24.2%, 50.6%, and 94.7% (P < 10(-29) ), respectively. In diagnosis of CIN2 or more severe lesion of the cervix, a combination test of methylated PCDHA4 or PCDHA13 from cervical scraping had a sensitivity, specificity, positive predictive value, and negative predictive value of 74.8%, 80.3%, 73%, and 81.8%, respectively. Testing of this combination from cervical scraping is equally sensitive but more specific than human papillomavirus (HPV) test in diagnosis of CIN2 or more severe lesions. The study disclosed a collective methylation of PCDH genes in cancer of cervix and other sites. At least two of them can be promising diagnostic markers for cervical cancer noninferior to HPV.


Asunto(s)
Cadherinas/genética , Metilación de ADN , Silenciador del Gen , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética , Adulto , Antimetabolitos Antineoplásicos/farmacología , Azacitidina/farmacología , Biomarcadores de Tumor/genética , Adhesión Celular/genética , Línea Celular Tumoral , Islas de CpG , Metilación de ADN/efectos de los fármacos , Progresión de la Enfermedad , Femenino , Sitios Genéticos , Humanos , Persona de Mediana Edad , Familia de Multigenes , Invasividad Neoplásica , Estadificación de Neoplasias , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/virología , Índice de Severidad de la Enfermedad
11.
Yi Chuan ; 25(1): 27-9, 2003 Jan.
Artículo en Zh | MEDLINE | ID: mdl-15639814

RESUMEN

The variation of chromosomes of Gansu Black pig was caused by infusion of Duroc blood. The chromosome length ratios of No.1,6,7,13 chromosomes in the line I of Gansu Black pig were higher than those in the line II. It showed that the homogeneity in line I was higher than in line II. The number of Ag-staining nucleolus organizers (Ag-NOR) was between 1-4 in the line I and II, the average No. of Ag-NOR was different obviously between the line I and the line II. This indicated that the activity of translation in rRNA in the line I was different in the line II.

12.
Assay Drug Dev Technol ; 10(5): 417-31, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22881347

RESUMEN

The renal outer medullary potassium (ROMK) channel is a member of the inwardly rectifying family of potassium (Kir) channels. ROMK (Kir1.1) is predominantly expressed in kidney where it plays a major role in the salt reabsorption process. Loss-of-function mutations in the human Kir1.1 channel are associated with antenatal Bartter's syndrome type II, a life-threatening salt and water balance disorder. Heterozygous carriers of Kir1.1 mutations associated with antenatal Bartter's syndrome have reduced blood pressure and a decreased risk of developing hypertension by age 60. These data suggest that Kir1.1 inhibitors could represent novel diuretics for the treatment of hypertension. Because little is known about the molecular pharmacology of Kir1.1 channels, assays that provide a robust, reliable readout of channel activity-while operating in high-capacity mode-are needed. In the present study, we describe high-capacity, 384- and 1,536-well plate, functional thallium flux, and IonWorks electrophysiology assays for the Kir1.1 channel that fulfill these criteria. In addition, 96-well (86)Rb(+) flux assays were established that can operate in the presence of 100% serum, and can provide an indication of the effect of a serum shift on compound potencies. The ability to grow Madin-Darby canine kidney cells expressing Kir1.1 in Transwell supports provides a polarized cell system that can be used to study the mechanism of Kir1.1 inhibition by different agents. All these functional Kir1.1 assays together can play an important role in supporting different aspects of drug development efforts during lead identification and/or optimization.


Asunto(s)
Descubrimiento de Drogas/métodos , Bloqueadores de los Canales de Potasio/metabolismo , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio de Rectificación Interna/antagonistas & inhibidores , Canales de Potasio de Rectificación Interna/metabolismo , Animales , Células CHO , Cricetinae , Cricetulus , Perros , Humanos , Células de Riñón Canino Madin Darby , Bloqueadores de los Canales de Potasio/sangre , Bloqueadores de los Canales de Potasio/química , Canales de Potasio de Rectificación Interna/sangre , Ratas , Talio/metabolismo
13.
Biochemistry ; 41(50): 14734-47, 2002 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-12475222

RESUMEN

Two peptides, ProTx-I and ProTx-II, from the venom of the tarantula Thrixopelma pruriens, have been isolated and characterized. These peptides were purified on the basis of their ability to reversibly inhibit the tetrodotoxin-resistant Na channel, Na(V) 1.8, and are shown to belong to the inhibitory cystine knot (ICK) family of peptide toxins interacting with voltage-gated ion channels. The family has several hallmarks: cystine bridge connectivity, mechanism of channel inhibition, and promiscuity across channels within and across channel families. The cystine bridge connectivity of ProTx-II is very similar to that of other members of this family, i.e., C(2) to C(16), C(9) to C(21), and C(15) to C(25). These peptides are the first high-affinity ligands for tetrodotoxin-resistant peripheral nerve Na(V) channels, but also inhibit other Na(V) channels (IC(50)'s < 100 nM). ProTx-I and ProTx-II shift the voltage dependence of activation of Na(V) 1.5 to more positive voltages, similar to other gating-modifier ICK family members. ProTx-I also shifts the voltage dependence of activation of Ca(V) 3.1 (alpha(1G), T-type, IC(50) = 50 nM) without affecting the voltage dependence of inactivation. To enable further structural and functional studies, synthetic ProTx-II was made; it adopts the same structure and has the same functional properties as the native peptide. Synthetic ProTx-I was also made and exhibits the same potency as the native peptide. Synthetic ProTx-I, but not ProTx-II, also inhibits K(V) 2.1 channels with 10-fold less potency than its potency on Na(V) channels. These peptides represent novel tools for exploring the gating mechanisms of several Na(V) and Ca(V) channels.


Asunto(s)
Péptidos/farmacología , Bloqueadores de los Canales de Sodio/farmacología , Canales de Sodio/metabolismo , Venenos de Araña/farmacología , Secuencia de Aminoácidos , Animales , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/aislamiento & purificación , Bloqueadores de los Canales de Calcio/farmacología , Línea Celular , Disulfuros/química , Electrofisiología , Humanos , Activación del Canal Iónico/efectos de los fármacos , Datos de Secuencia Molecular , Péptidos/química , Péptidos/aislamiento & purificación , Bloqueadores de los Canales de Potasio/química , Bloqueadores de los Canales de Potasio/aislamiento & purificación , Bloqueadores de los Canales de Potasio/farmacología , Ratas , Ratas Wistar , Bloqueadores de los Canales de Sodio/química , Bloqueadores de los Canales de Sodio/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Venenos de Araña/química , Venenos de Araña/aislamiento & purificación
14.
Biochemistry ; 43(30): 9866-76, 2004 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-15274641

RESUMEN

Sodium channel blockers are used clinically to treat a number of neuropathic pain conditions, but more potent and selective agents should improve on the therapeutic index of currently used drugs. In a high-throughput functional assay, a novel sodium channel (Na(V)) blocker, N-[[2'-(aminosulfonyl)biphenyl-4-yl]methyl]-N'-(2,2'-bithien-5-ylmethyl)succinamide (BPBTS), was discovered. BPBTS is 2 orders of magnitude more potent than anticonvulsant and antiarrhythmic sodium channel blockers currently used to treat neuropathic pain. Resembling block by these agents, block of Na(V)1.2, Na(V)1.5, and Na(V)1.7 by BPBTS was found to be voltage- and use-dependent. BPBTS appeared to bind preferentially to open and inactivated states and caused a dose-dependent hyperpolarizing shift in the steady-state availability curves for all sodium channel subtypes tested. The affinity of BPBTS for the resting and inactivated states of Na(V)1.2 was 1.2 and 0.14 microM, respectively. BPBTS blocked Na(V)1.7 and Na(V)1.2 with similar potency, whereas block of Na(V)1.5 was slightly more potent. The slow tetrodotoxin-resistant Na(+) current in small-diameter DRG neurons was also potently blocked by BPBTS. [(3)H]BPBTS bound with high affinity to a single class of sites present in rat brain synaptosomal membranes (K(d) = 6.1 nM), and in membranes derived from HEK cells stably expressing Na(V)1.5 (K(d) = 0.9 nM). BPBTS dose-dependently attenuated nociceptive behavior in the formalin test, a rat model of tonic pain. On the basis of these findings, BPBTS represents a structurally novel and potent sodium channel blocker that may be used as a template for the development of analgesic agents.


Asunto(s)
Amidas/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Proteínas Musculares/metabolismo , Dimensión del Dolor/efectos de los fármacos , Bloqueadores de los Canales de Sodio/uso terapéutico , Canales de Sodio/metabolismo , Amidas/síntesis química , Amidas/metabolismo , Analgésicos/síntesis química , Analgésicos/metabolismo , Analgésicos/uso terapéutico , Animales , Sitios de Unión , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/metabolismo , Encéfalo/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Formaldehído/administración & dosificación , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Humanos , Ratones , Proteínas Musculares/biosíntesis , Proteínas Musculares/genética , Canal de Sodio Activado por Voltaje NAV1.2 , Canal de Sodio Activado por Voltaje NAV1.5 , Canal de Sodio Activado por Voltaje NAV1.7 , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Técnicas de Placa-Clamp , Ratas , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/biosíntesis , Bloqueadores de los Canales de Sodio/síntesis química , Bloqueadores de los Canales de Sodio/metabolismo , Canales de Sodio/biosíntesis , Canales de Sodio/genética , Succinatos , Sinaptosomas/metabolismo , Tetrodotoxina/antagonistas & inhibidores , Tetrodotoxina/química
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