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1.
Angew Chem Int Ed Engl ; : e202413898, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223782

RESUMEN

Antiferroelectric (AFE) has emerged as a promising branch of electroactive materials, due to their intriguing physical attributes stemming from the electric field-induced antipolar-to-polar phase transformation. However, the requirement of an extremely high electric field strength to switch adjacent sublattice polarization poses great challenges for exploiting molecular AFE system. Although photoirradiation is striking as a noncontact and nondestructive manipulation tool to optimize physical properties, the optical control of antiferroelectricity is still unexplored. Here, by adopting light-sensitive triiodide I3- anion into the 2D perovskite family, we have designed the first I3--intercalated molecular AFE of (t-ACH)2EA2Pb3I10(I3)0.5·((H3O)(H2O))0.5 (1, t-ACH = trans-4-aminomethyl-1-cyclohexanecarboxylate, EA = ethylammonium). The I3--intercalating gives an ultra-narrow bandgap of 1.65 eV with strong absorption. In terms of AFE structure, the anti-parallel alignment of electric dipoles results in a spontaneous polarization of 4.3 µC/cm2. Strikingly, 1 merely shows AFE behaviour in the dark even under ultrahigh voltage, while the field-induced ferroelectric state can be facilely obtained upon visible illumination. Such unprecedented photo-assisted phase switching ascribes to the incorporation of photoactive I3- anions, which reduce the AFE-to-ferroelectric switching barrier for 1. This pioneering work on the photo-assisting transformation of ferroic orders paves a new way to develop future photoactive materials with significant potential applications.

2.
Clin Epigenetics ; 16(1): 103, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103963

RESUMEN

BACKGROUND: Childhood maltreatment (CM) is linked to long-term adverse health outcomes, including accelerated biological aging and cognitive decline. This study investigates the relationship between CM and various aging biomarkers: telomere length, facial aging, intrinsic epigenetic age acceleration (IEAA), GrimAge, HannumAge, PhenoAge, frailty index, and cognitive performance. METHODS: We conducted a Mendelian randomization (MR) study using published GWAS summary statistics. Aging biomarkers included telomere length (qPCR), facial aging (subjective evaluation), and epigenetic age markers (HannumAge, IEAA, GrimAge, PhenoAge). The frailty index was calculated from clinical assessments, and cognitive performance was evaluated with standardized tests. Analyses included Inverse-Variance Weighted (IVW), MR Egger, and Weighted Median (WM) methods, adjusted for multiple comparisons. RESULTS: CM was significantly associated with shorter telomere length (IVW: ß = - 0.1, 95% CI - 0.18 to - 0.02, pFDR = 0.032) and increased HannumAge (IVW: ß = 1.33, 95% CI 0.36 to 2.3, pFDR = 0.028), GrimAge (IVW: ß = 1.19, 95% CI 0.19 to 2.2, pFDR = 0.040), and PhenoAge (IVW: ß = 1.4, 95% CI 0.12 to 2.68, pFDR = 0.053). A significant association was also found with the frailty index (IVW: ß = 0.31, 95% CI 0.13 to 0.49, pFDR = 0.006). No significant associations were found with facial aging, IEAA, or cognitive performance. CONCLUSIONS: CM is linked to accelerated biological aging, shown by shorter telomere length and increased epigenetic aging markers. CM was also associated with increased frailty, highlighting the need for early interventions to mitigate long-term effects. Further research should explore mechanisms and prevention strategies.


Asunto(s)
Envejecimiento , Biomarcadores , Análisis de la Aleatorización Mendeliana , Humanos , Análisis de la Aleatorización Mendeliana/métodos , Biomarcadores/sangre , Envejecimiento/genética , Epigénesis Genética/genética , Masculino , Femenino , Fragilidad/genética , Niño , Estudio de Asociación del Genoma Completo/métodos , Maltrato a los Niños/psicología , Maltrato a los Niños/estadística & datos numéricos , Telómero/genética , Adulto , Anciano , Persona de Mediana Edad
3.
BMC Pediatr ; 24(1): 451, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39010003

RESUMEN

BACKGROUND: To investigate the relationship between cord blood levels of Angiopoietin-1 (Ang-1) and S-endoglin (sCD105) and bronchopulmonary dysplasia (BPD) in preterm infants. METHODS: Sixty-one preterm infants admitted to the neonatal intensive care unit of the study hospital between July 2021 and September 2022 were included. Cord blood was collected after the birth of premature infants. Ang-1 and sCD105 levels were quantified using the vascular endothelial growth factor enzyme-linked immunosorbent assay. Preterm infants were divided into BPD and non-BPD groups, and differences in Ang-1 and sCD105 levels between the two groups were compared. A binary logistic model was used to assess the association between low and high levels Ang-1 and BPD in preterm infants. RESULTS: In the study, there were 20 preterm infants with BPD (32.8%) and 41 preterm infants with non-BPD (67.2%). Ang-1 concentration levels were lower in the BPD group than in the non-BPD group (7105.43 (5617.01-8523.00) pg/ml vs. 10488.03 (7946.19-15962.77) pg/ml, P = 0.027). However, the sCD105 concentration levels were not significantly different between the BPD and non-BPD groups (P = 0.246). A median Ang-1 concentration of 8800.40 pg/ml was calculated. Logistic regression analysis showed that after adjusting for gestational age, birth weight, and maternal prenatal steroid hormone application, the odds ratio (OR) was 8.577 for the risk of BPD in preterm infants with Ang-1 concentrations of ≤ 8800.40 pg/ml compared to those with Ang-1 concentrations of > 8800.40 pg/ml (OR: 8.577, 95% confidence interval: 1.265-58.155, P = 0.028). CONCLUSION: Our study indicated that Ang-1 levels in the cord blood of preterm infants may be associated the risk of BPD. In the future, we will continue to conduct study with large samples.


Asunto(s)
Angiopoyetina 1 , Displasia Broncopulmonar , Endoglina , Sangre Fetal , Recien Nacido Prematuro , Humanos , Displasia Broncopulmonar/sangre , Recién Nacido , Endoglina/sangre , Recien Nacido Prematuro/sangre , Sangre Fetal/química , Sangre Fetal/metabolismo , Femenino , Masculino , Angiopoyetina 1/sangre , Biomarcadores/sangre , Modelos Logísticos
4.
Food Funct ; 15(12): 6657-6672, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38814101

RESUMEN

Background: Oxidative stress plays an important role in the occurrence and pathological process of numerous human diseases. A bidirectional relationship was found between sleep disorders and oxidative stress. However, the association between circulating antioxidant levels and the risk of sleep disorders at the population-scale has yet to be determined. Methods: We used the dataset from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 data release cycle and included 3062 adult participants aged 25-75 years. The circulating antioxidants levels in serum were measured, and the sleep status was assessed by self-reported sleep disorder questionnaire tests. We investigated the association and exposure-response relationship between the 12 main circulating antioxidants and sleep disorders using a generalized additive model (GAM), multiple linear, binary logistic, and restricted cubic spline (RCS) regression models. Multiple sensitivity analyses were conducted to validate the results of our study. Results: Significantly lower serum concentrations of ten antioxidants were observed in the group which had trouble sleeping symptoms compared to the control group. After adjusting for all the covariates, the binary logistic regression models indicated that six of the circulating antioxidants including alpha-carotene, alpha-cryptoxanthin, trans-beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin, and vitamin C, showed a significant association with the risk of overall trouble sleeping symptoms, with odds ratios corresponding to 0.88 (95% CI: 0.80-0.96), 0.74 (95% CI: 0.62-0.87), 0.87 (95% CI: 0.79-0.97), 0.85 (95% CI: 0.75-0.95), 0.72 (95% CI: 0.61-0.84), and 0.83 (95% CI: 0.74-0.93), respectively. The GAM and multiple linear regression revealed similar associations whereas the RCS regression models further confirmed their significant negative exposure-response relationship. Conclusions: The circulating carotenoids and vitamin C levels were negatively correlated with the risk of sleep disorders. Higher circulating antioxidant levels were significantly associated with a lower risk of sleep disorders. The potential health risk of low circulating antioxidants levels was higher in the female population than in the male population.


Asunto(s)
Antioxidantes , Encuestas Nutricionales , Trastornos del Sueño-Vigilia , Humanos , Persona de Mediana Edad , Antioxidantes/análisis , Antioxidantes/metabolismo , Masculino , Femenino , Adulto , Trastornos del Sueño-Vigilia/sangre , Trastornos del Sueño-Vigilia/epidemiología , Anciano , Estrés Oxidativo , Carotenoides/sangre , Ácido Ascórbico/sangre
5.
Artículo en Inglés | MEDLINE | ID: mdl-38607211

RESUMEN

Objective: To explore the application value of transabdominal ultrasonography in the diagnosis of gastrointestinal malignant tumors. Methods: This study retrospectively analyzed the transabdominal ultrasound imaging data of 284 patients with gastrointestinal tumors admitted to our hospital from April 2019 to March 2022 and assessed the accuracy of transabdominal ultrasound in diagnosing different types of gastrointestinal tumor diseases. The diagnostic accuracy of transabdominal ultrasonography for TNM staging of gastrointestinal malignancies was calculated. Results: The sensitivity and specificity of transabdominal ultrasonography in the diagnosis of gastric cancer were (82.40% and 83.72%, respectively), colon cancer (77.78% and 88.35%, respectively), gastric stromal tumor (95.45% and 93.65%, respectively), gastric lymphoma (72.22% and 94.66%, respectively), colorectal lymphoma (80.00% and 95.42%, respectively), gastric mucosal hypertrophy (85.71% and 96.69%, respectively), and pyloric hypertrophy (92.59% and 97.79%, respectively). Among the 284 patients included, 152 patients had malignant tumors, including 34 patients with stage I, 30 patients with stage II, 51 patients with stage III, and 37 patients with stage IV. The accuracy of transabdominal ultrasonography for TNM staging of gastrointestinal malignancies was 85.53% (130/152). Conclusion: Transabdominal ultrasonography shows promise as a diagnostic tool for gastrointestinal malignant tumors; however, it is recommended to be used in conjunction with other detection methods such as fibrous gastrointestinal tract examination to minimize the risk of missed diagnoses and misdiagnoses. The study highlights the potential of transabdominal ultrasonography as a non-invasive and accessible diagnostic method for gastrointestinal malignancies. Further research and advancements in imaging technologies are crucial for enhancing diagnostic capabilities and improving patient outcomes in the future.

6.
Mol Nutr Food Res ; 68(7): e2300469, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38522025

RESUMEN

SCOPE: 3,5-Dihydroxy-4-methoxybenzyl alcohol (DHMBA) is found in oyster extracts in recent years and is reported to have antioxidant activity. Although it has been reported to be protective in various models of oxidative stress, the therapeutic effect of DHMBA on neurological damage caused by aging remains to be demonstrated. METHODS AND RESULTS: The present study investigates the potential functions of DHMBA in brain of old C57BL/6J mice and aging cell model. Administration of DHMBA improves working memory, reduces anxiety behavior, decreases the expression levels of cell cycle proteins, cycin-dependent kinase inhibitor 1(P21) and peptidase inhibitor 16(P16)  and inhibits neuronal loss in old mice. The data obtained from the aging cell model are consistent with those from the old mice. The interaction between DHMBA and Kelch-like ECH-associated protein 1 (Keap1) is predicted by molecular docking assay, and then it is verified by co-immunopricipitation (CoIP) that factor red lineage 2-related factor 2 (Nrf2)-Keap1 protein-protein interaction is inhibited by DHMBA. Protein levels of Nrf2 and its target genes, such as glutathione peroxidase 4(GPX4) and heme oxygenase 1 (HO-1), are detected in old mice and aging cell model. CONCLUSION: This study provides new evidence that explores the antioxidant mechanism of DHMBA and implies a potential role of DHMBA on antiaging in brain.


Asunto(s)
Alcoholes Bencílicos , Crassostrea , Ratones , Animales , Crassostrea/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Simulación del Acoplamiento Molecular , Ratones Endogámicos C57BL , Antioxidantes/farmacología , Antioxidantes/metabolismo , Estrés Oxidativo , Etanol/farmacología , Encéfalo/metabolismo
7.
J Am Chem Soc ; 146(12): 8298-8307, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38498306

RESUMEN

Antiferroelectric materials with an electrocaloric effect (ECE) have been developed as promising candidates for solid-state refrigeration. Despite the great advances in positive ECE, reports on negative ECE remain quite scarce because of its elusive physical mechanism. Here, a giant negative ECE (maximum ΔS ∼ -33.3 J kg-1 K-1 with ΔT ∼ -11.7 K) is demonstrated near room temperature in organometallic perovskite, iBA2EA2Pb3I10 (1, where iBA = isobutylammonium and EA = ethylammonium), which is comparable to the greatest ECE effects reported so far. Moreover, the ECE efficiency ΔS/ΔE (∼1.85 J cm kg-1 K-1 kV-1) and ΔT/ΔE (∼0.65 K cm kV-1) are almost 2 orders of magnitude higher than those of classical inorganic ceramic ferroelectrics and organic polymers, such as BaTiO3, SrBi2Ta2O9, Hf1/2Zr1/2O2, and P(VDF-TrFE). As far as we know, this is the first report on negative ECE in organometallic hybrid perovskite ferroelectric. Our experimental measurement combined with the first-principles calculations reveals that electric field-induced antipolar to polar structural transformation results in a large change in dipolar ordering (from 6.5 to 45 µC/cm2 under the ΔE of 18 kV/cm) that is closely related to the entropy change, which plays a key role in generating such giant negative ECE. This discovery of field-induced negative ECE is unprecedented in organometallic perovskite, which sheds light on the exploration of next-generation refrigeration devices with high cooling efficiency.

8.
J Med Chem ; 67(7): 5758-5782, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38511649

RESUMEN

Eukaryotic translation initiation factor 2B (eIF2B) is a key component of the integrated stress response (ISR), which regulates protein synthesis and stress granule formation in response to cellular insult. Modulation of the ISR has been proposed as a therapeutic strategy for treatment of neurodegenerative diseases such as vanishing white matter (VWM) disease and amyotrophic lateral sclerosis (ALS) based on its ability to improve cellular homeostasis and prevent neuronal degeneration. Herein, we report the small-molecule discovery campaign that identified potent, selective, and CNS-penetrant eIF2B activators using both structure- and ligand-based drug design. These discovery efforts culminated in the identification of DNL343, which demonstrated a desirable preclinical drug profile, including a long half-life and high oral bioavailability across preclinical species. DNL343 was progressed into clinical studies and is currently undergoing evaluation in late-stage clinical trials for ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral , Leucoencefalopatías , Enfermedades Neurodegenerativas , Humanos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/metabolismo , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/metabolismo , Mutación , Factor 2B Eucariótico de Iniciación/genética , Factor 2B Eucariótico de Iniciación/metabolismo , Encéfalo/metabolismo , Leucoencefalopatías/metabolismo
9.
Medicine (Baltimore) ; 103(10): e37372, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457566

RESUMEN

This study aimed to investigate the value of placental real-time shear wave elastography combined with three-dimensional power Doppler index (3D-PDI) in the prediction of preeclampsia. We conducted a retrospective study selecting 60 pregnant women diagnosed with preeclampsia as the experimental group and 60 normal pregnant women as the control group from January 2021 to December 2022. The elastic modulus values of different regions of the placenta and placental 3D-PDI were detected and compared between the two groups. The ROC curve was used to evaluate the diagnostic value of each parameter, alone or in combination, for preeclampsia. The study findings demonstrated that the elastic modulus values of different regions of the placenta and 3D-PDI of the two groups have statistical significance. The values of SWE, VI, FI, and VFI are different in prediction of preeclampsia, and the combination of various parameters can improve the prediction value. Overall, our study provides a valuable method for the prediction of preeclampsia with the advantages of non-invasiveness, efficiency, and simplicity.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Preeclampsia , Embarazo , Femenino , Humanos , Placenta/diagnóstico por imagen , Preeclampsia/diagnóstico por imagen , Estudios Retrospectivos , Diagnóstico por Imagen de Elasticidad/métodos , Ultrasonografía Prenatal/métodos , Imagenología Tridimensional/métodos , Ultrasonografía Doppler
10.
Theor Appl Genet ; 137(1): 31, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267732

RESUMEN

KEY MESSAGE: A co-located novel QTL for TFS, FPs, FMs, FFS, FFPs, KWS, and KWPs with potential of improving wheat yield was identified and validated. Spike-related traits, including fertile florets per spike (FFS), kernel weight per spike (KWS), total florets per spike (TFS), florets per spikelet (FPs), florets in the middle spikelet (FMs), fertile florets per spikelet (FFPs), and kernel weight per spikelet (KWPs), are key traits in improving wheat yield. In the present study, quantitative trait loci (QTL) for these traits evaluated under various environments were detected in a recombinant inbred line population (msf/Chuannong 16) mainly genotyped using the 16 K SNP array. Ultimately, we identified 60 QTL, but only QFFS.sau-MC-1A for FFS was a major and stably expressed QTL. It was located on chromosome arm 1AS, where loci for TFS, FPs, FMs, FFS, FFPs, KWS, and KWPs were also simultaneously co-mapped. The effect of QFFS.sau-MC-1A was further validated in three independent segregating populations using a Kompetitive Allele-Specific PCR marker. For the co-located QTL, QFFS.sau-MC-1A, the presence of a positive allele from msf was associate with increases for all traits: + 12.29% TFS, + 10.15% FPs, + 13.97% FMs, + 17.12% FFS, + 14.75% FFPs, + 22.17% KWS, and + 19.42% KWPs. Furthermore, pleiotropy analysis showed that the positive allele at QFFS.sau-MC-1A simultaneously increased the spike length, spikelet number per spike, and thousand-kernel weight. QFFS.sau-MC-1A represents a novel QTL for marker-assisted selection with the potential for improving wheat yield. Four genes, TraesCS1A03G0012700, TraesCS1A03G0015700, TraesCS1A03G0016000, and TraesCS1A03G0016300, which may affect spike development, were predicted in the physical interval harboring QFFS.sau-MC-1A. Our results will help in further fine mapping QFFS.sau-MC-1A and be useful for improving wheat yield.


Asunto(s)
Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Fitomejoramiento , Fenotipo , Genotipo
11.
Chemosphere ; 349: 140690, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37995973

RESUMEN

Volatile organic compounds (VOCs) are important contributors to air pollution. VOCs exposure was associated with various human diseases. Depression is one of the most prevalent mental disorders and poses a serious mental health burden. Although VOCs are neurotoxic and can damage the central nervous system, the association between VOCs exposure and depression remains obscure. Based on data from the National Health and Nutrition Examination Survey, we included 5676 adult individuals and 15 major components of urinary volatile organic compound metabolites (mVOCs). We comprehensively evaluated the potential association between each single urinary mVOC exposure and depressive symptoms using binary logistic and restricted cubic spline regression, whereas the weighted quantile sum regression and least absolute shrinkage and selection operator regression model were used to explore the mixture co-exposure association. The results indicated significantly higher mean concentrations of the 11 urinary mVOC components in the depression group than that in the non-depression group. And 12 mVOC components had a significantly positive association with depression. The overall effect of all 15 mVOCs components was also significantly positive. The corresponding odds ratio was 1.56 (95%CI: 1.2-2.03) in the categorical variable model and the regression coefficient was 0.36 (95%CI: 0.12-0.6) in the numerical variable model. Five urinary mVOCs (URXCYM, URXPHG, URX34 M, URXMB3, and URXAMC) were identified as the most relevant components associated with depression, with 89.06% total weights in the categorical variable model and 89.39% in the numerical variable model. The mVOCs were the biomarkers of VOCs, their concentrations in urine could specifically represent the contents of their metabolic parents in the human body. Considering that the metabolic parents of the above five mVOCs were predominantly acrylonitrile, toluene, styrene, acrylamide, 1,3-Butadiene, and xylenes, our results further indicated that exposure to these VOCs was closely related to depression, and more attention should be paid to the mental health risks of VOCs exposure.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Adulto , Humanos , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Encuestas Nutricionales , Monitoreo del Ambiente/métodos , Depresión/epidemiología
12.
Chem Sci ; 14(37): 10347-10352, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37772112

RESUMEN

The ferro-pyro-phototronic (FPP) effect, coupling photoexcited pyroelectricity and photovoltaics, paves an effective way to modulate charge-carrier behavior of optoelectronic devices. However, reports of promising FPP-active systems remain quite scarce due to a lack of knowledge on the coupling mechanism. Here, we have successfully enhanced the FPP effect in a series of ferroelectrics, BA2Cs1-xMAxPb2Br7 (BA = butylammonium, MA = methylammonium, 0 ≤ x ≤ 0.34), rationally assembled by mixing cage cations into 2D metal-halide perovskites. Strikingly, chemical alloying of Cs+/MA+ cations leads to the reduction of exciton binding energy, as verified by the x = 0.34 component; this facilitates exciton dissociation into free charge-carriers and boosts photo-activities. The crystal detector thus displays enhanced FPP current at zero bias, almost more than 10 times higher than that of the x = 0 prototype. As an innovative study on the FPP effect, this work affords new insight into the fundamental principle of ferroelectrics and creates a new strategy for self-driven photodetection.

13.
Nat Commun ; 14(1): 5821, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37726264

RESUMEN

Broadband spectral photoresponse has shown bright prospects for various optoelectronic devices, while fulfilling high photoactivity beyond the material bandgap is a great challenge. Here, we present a molecular pyroelectric, N-isopropylbenzylaminium trifluoroacetate (N-IBATFA), of which the broadband photo-pyroelectric effects allow for self-driven wide spectral photodetection. As a simple organic binary salt, N-IBATFA possesses a large polarization (~9.5 µC cm-2), high pyroelectric coefficient (~6.9 µC cm-2 K-1) and figures-of-merits (FV = 187.9 × 10-2 cm2 µC-1; FD = 881.5 × 10-5 Pa-0.5) comparable to the state-of-art pyroelectric materials. Particularly, such intriguing attributes endow broadband photo-pyroelectric effect, namely, transient currents covering ultraviolet (UV, 266 nm) to near-infrared (NIR, 1950 nm) spectral regime, which breaks the restriction of its optical absorption and thus allows wide UV-NIR spectral photodetection. Our finding highlights the potential of molecular system as high-performance candidates toward self-powered wide spectral photodetection.

14.
Angew Chem Int Ed Engl ; 62(45): e202309416, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37733923

RESUMEN

Ferroelectric photovoltaics driven by spontaneous polarization (Ps ) holds a promise for creating the next-generation optoelectronics, spintronics and non-volatile memories. However, photoactive ferroelectrics are quite scarce in single homogeneous phase, owing to the severe Ps fatigue caused by leakage current of photoexcited carriers. Here, through combining inorganic and organic components as building blocks, we constructed a series of ferroelectric semiconductors of 2D hybrid perovskites, (HA)2 (MA)n-1 Pbn Br3n+1 (n=1-5; HA=hexylamine and MA=methylamine). It is intriguing that their Curie temperatures are greatly enhanced by reducing the thickness of inorganic frameworks from MAPbBr3 (n=∞, Tc =239 K) to n=2 (Tc =310 K, ΔT=71 K). Especially, on account of the coupling of room-temperature ferroelectricity (Ps ≈1.5 µC/cm2 ) and photoconductivity, n=3 crystal wafer was integrated as channel field effect transistor that shows excellent a large short-circuit photocurrent ≈19.74 µA/cm2 . Such giant photocurrents can be modulated through manipulating gate voltage in a wide range (±60 V), exhibiting gate-tunable memory behaviors of three current states ("-1/0/1" states). We believe that this work sheds light on further exploration of ferroelectric materials toward new non-volatile memory devices.

15.
Small ; 19(49): e2303909, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37612806

RESUMEN

Photorefractive effect of ferroelectrics refers to the light-induced change of refractive index, which is an optical controlling avenue in holographic storage and image processing. For most ferroelectrics, however, the small photorefractive effect (10-5 -10-4 ) hinders their practical application and it is urgent to exploit new photorefractive system. Here, for the first time, strong photorefractive effects are achieved in a 2D metal-halide ferroelectric, [CH3 (CH2 )3 NH3 ]2 (CH3 NH3 )Pb2 Cl7 (1), showing large spontaneous polarization (≈4.1 µC cm-2 ) and wide optical bandgap (≈3.20 eV). Notably, under light irradiation, 1 enables a large variation of refractive indices up to ≈ 1× 10-3 , being one order higher than the existing materials and comparable to the state-of-the-art inorganic ferroelectrics. This intriguing photorefractive behavior involves with the sharp variation of polarization caused by photo-pyroelectricity. As the first report of 2D metal-halide photorefractive ferroelectric, this work sheds light on optical controlling of physical properties in electric-ordered materials.

16.
Theor Appl Genet ; 136(9): 181, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37550493

RESUMEN

KEY MESSAGE: A likely new locus QSns.sau-MC-3D.1 associated with SNS showing no negative effect on yield-related traits compared to WAPO1 was identified and validated in various genetic populations under multiple environments. The number of spikelets per spike (SNS) is one of the crucial factors determining wheat yield. Thus, improving our understanding of the genes that regulate SNS could help develop wheat varieties with higher yield. In this study, a recombinant inbred line (RIL) population (MC) containing 198 lines derived from a cross between msf and Chuannong 16 (CN16) was used to construct a genetic linkage map using the GenoBaits Wheat 16 K Panel. The genetic map contained 5,991 polymorphic SNP markers spanning 2,813.25 cM. A total of twelve QTL for SNS were detected, and two of them, i.e., QSns.sau-MC-3D.1 and QSns.sau-MC-7A, were stably expressed. QSns.sau-MC-3D.1 had high LOD values ranging from 4.99 to 11.06 and explained 9.71-16.75% of the phenotypic variation. Comparison of QSns.sau-MC-3D.1 with previously reported SNS QTL suggested that it is likely a novel one, and two kompetitive allele-specific PCR (KASP) markers were further developed. The positive effect of QSns.sau-MC-3D.1 was also validated in three biparental populations and a diverse panel containing 388 Chinese wheat accessions. Genetic analysis indicated that WHEAT ORTHOLOG OFAPO1 (WAPO1) was a candidate gene for QSns.sau-MC-7A. Pyramiding of QSns.sau-MC-3D.1 and WAP01 had a great additive effect increasing SNS by 7.10%. Correlation analysis suggested that QSns.sau-MC-3D.1 was likely independent of effective tiller number, plant height, spike length, anthesis date, and thousand kernel weight. However, the H2 haplotype of WAPO1 may affect effective tiller number and plant height. These results indicated that utilization of QSns.sau-MC-3D.1 should be given priority for wheat breeding. Geographical distribution analysis showed that the positive allele of QSns.nsau-MC-3D.1 was dominant in most wheat-producing regions of China, and it has been positively selected among modern cultivars released in China since the 1940s. Gene prediction, qRT-PCR analysis, and sequence alignment suggested that TraesCS3D03G0216800 may be the candidate gene of QSns.nsau-MC-3D.1. Taken together, these results enrich our understanding of the genetic basis of wheat SNS and will be useful for fine mapping and cloning of the gene underlying QSns.sau-MC-3D.1.


Asunto(s)
Sitios de Carácter Cuantitativo , Triticum , Mapeo Cromosómico/métodos , Triticum/genética , Fitomejoramiento , Fenotipo
17.
Nat Commun ; 14(1): 2420, 2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37105974

RESUMEN

Halide double perovskites have recently emerged as an environmentally green candidate toward electronic and optoelectronic applications owing to their non-toxicity and versatile physical merits, whereas study on high-temperature antiferroelectric (AFE) with excellent anti-breakdown property remains a huge blank in this booming family. Herein, we present the first high-temperature AFE of the lead-free halide double perovskites, (CHMA)2CsAgBiBr7 (1, where CHMA+ is cyclohexylmethylammonium), by incorporating a flexible organic spacer cation. The typical double P-E hysteresis loops and J-E curves reveal its concrete high-temperature AFE behaviors, giving large polarizations of ~4.2 µC/cm2 and a high Curie temperature of 378 K. Such merits are on the highest level of molecular AFE materials. Particularly, the dynamic motional ordering of CHMA+ cation contributes to the formation of antipolar alignment and high electric breakdown field strength up to ~205 kV/cm with fatigue endurance over 104 cycles, almost outperforming the vast majority of molecule counterparts. This is the first demonstration of high-temperature AFE properties in the halide double perovskites, which will promote the exploration of new "green" candidates for anti-breakdown energy storage capacitor.

18.
Chemistry ; 29(33): e202300876, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37062802

RESUMEN

Two-dimensional (2D) hybrid perovskite materials have been widely used for polarization-sensitive photodetection due to their fascinating optical and physical attributes. However, studies on those materials that enable strong polarized-light activities under a weak-light condition remain quite scarce. Here, by tailoring aromatic cation into 3D prototype, we have successfully obtained a new 2D hybrid perovskite, (FPEA)2 (MA)Pb2 Br7 (1, where FPEA is 4-fluorophenethylammonium and MA is methylammonium). The alternative alignment of inorganic and organic structural components results in significant anisotropy, including optical absorption and electric conductivity. The coupling effect of these anisotropic properties in 1 gives rise to strong dichroic activities toward detecting polarized light. Especially, under weak light intensity (∼330 nW/cm2 ), it can still generate a large polarization ratio up to 1.35, which is even higher than those of some typical 2D materials (i. e., GeSe ∼1.09). Besides, single crystal-based photodetector of 1 displays fascinating detecting performances, including large photocurrent on/off ratio (∼104 ), fast response time (∼154/182 µs) and excellent antifatigued stability. These findings disclose the potentials of 1 as a robust candidate for detecting weak polarized light, which has practical applications in the field of polarized optoelectronics.


Asunto(s)
Compuestos de Calcio , Luz , Anisotropía , Conductividad Eléctrica
19.
Small ; 19(16): e2207393, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36651018

RESUMEN

The bulk anomalous photovoltaic (BAPV) effect of acentric materials refers to a distinct concept from traditional semiconductor-based devices, of which the above-bandgap photovoltage hints at a promise for solar-energy conversion. However, it is still a challenge to exploit new BAPV-active systems due to the lacking of knowledge on the structural origin of this concept. BAPV effects in single crystals of a 2D lead-free double perovskite, (BBA)2 CsAgBiBr7 (1, BBA = 4-bromobenzylammonium), tailored by mixing aromatic and alkali cations in the confined architecture to form electric polarization are acquired here. Strikingly, BAPV effects manifested by above-bandgap photovoltage (VOC ) show unique attributes of directional anisotropy and positive dependence on electrode spacing. The driving source stems from orientations of the polar aromatic spacer and Cs+ ion drift, being different from the known built-in asymmetry photovoltaic heterojunctions. As the first demonstration of the BAPV effect in the double perovskites, the results will enrich the family of environmentally green BAPV-active candidates and further facilitate their new optoelectronic application.

20.
ACS Cent Sci ; 9(12): 2350-2357, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38161377

RESUMEN

The light-induced pyroelectric effect (LPE) has shown a great promise in the application of optoelectronic devices, especially for self-powered detection and imaging. However, it is quite challenging and scarce to achieve LPE in the X-ray region. For the first time, we report X-ray LPE in a single-phase ferroelectric of (NPA)2(EA)2Pb3Br10 (1, NPA = neopentylamine, EA = ethylamine), adopting a two-dimensional trilayered perovskite motif, which has a large spontaneous polarization of ∼3.7 µC/cm2. Its ferroelectricity allows for significant LPE in the wavelength range of ordinary visible light. Strikingly, the X-ray LPE is observed in 1, which endows remarkable self-powered X-ray responses at 0 bias, including sensitivity up to 225 µC Gy-1 cm-2 and a low detection limit of ∼83.4 nGy s-1, being almost 66 times lower than the requirement for medical diagnostics (∼5.5 µGy s-1). This work not only develops a new mode for X-ray detection but also provides valuable insights for future photoelectric device application.

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