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1.
Opt Lett ; 48(13): 3579-3582, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37390185

RESUMEN

Employing a photosensitive donor/acceptor planar heterojunction (DA-PHJ) with complementary optical absorption as the active layer is one of the key strategies for realizing broad spectral organic photodiodes (BS-OPDs). To achieve superior optoelectronic performance, it is vital to optimize the thickness ratio of the donor layer to acceptor layer (the DA thickness ratio) in addition to the optoelectronic properties of the DA-PHJ materials. In this study, we realized a BS-OPD exploiting tin(II) phthalocyanine (SnPc)/3,4,9,10-perylenete-acarboxylic dianhydride (PTCDA) as the active layer and investigated the effect of the DA thickness ratio on the device performance. The results showed that the DA thickness ratio has a significant impact on the device performance, and an optimized DA thickness ratio of 30:20 was found. Upon the optimization of the DA thickness ratio, improvements of 187% in photoresponsivity and 144% in specific detectivity were achieved on average. Trap-free space-charge-limited photocarrier transport and balanced optical absorption over the wavelength range can be ascribed to the improved performance at the optimized DA thickness ratio. These results establish a solid photophysical foundation for improving the performance of BS-OPDs via thickness ratio optimization.


Asunto(s)
Isoindoles , Estaño
2.
Nanomaterials (Basel) ; 13(7)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37049263

RESUMEN

An infrared photodetector is a critical component that detects, identifies, and tracks complex targets in a detection system. Infrared photodetectors based on 3D bulk materials are widely applied in national defense, military, communications, and astronomy fields. The complex application environment requires higher performance and multi-dimensional capability. The emergence of 2D materials has brought new possibilities to develop next-generation infrared detectors. However, the inherent thickness limitations and the immature preparation of 2D materials still lead to low quantum efficiency and slow response speeds. This review summarizes 2D/3D hybrid van der Waals heterojunctions for infrared photodetection. First, the physical properties of 2D and 3D materials related to detection capability, including thickness, band gap, absorption band, quantum efficiency, and carrier mobility, are summarized. Then, the primary research progress of 2D/3D infrared detectors is reviewed from performance improvement (broadband, high-responsivity, fast response) and new functional devices (two-color detectors, polarization detectors). Importantly, combining low-doped 3D and flexible 2D materials can effectively improve the responsivity and detection speed due to a significant depletion region width. Furthermore, combining the anisotropic 2D lattice structure and high absorbance of 3D materials provides a new strategy in high-performance polarization detectors. This paper offers prospects for developing 2D/3D high-performance infrared detection technology.

3.
Rice (N Y) ; 16(1): 21, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37084146

RESUMEN

BACKGROUND: Soil salinization is a major abiotic environmental stress factor threatening crop production throughout the world. Salt stress drastically affects the growth, development, and grain yield of rice (Oryza sativa L.), and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand. Receptor-like cytoplasmic kinases (RLCKs) play essential roles in plant growth, development and responses to environmental stresses. However, little is known about their functions in salt stress. Previous reports have demonstrated that overexpression of an RLCK gene SALT TOLERANCE KINASE (STK) enhances salt tolerance in rice, and that STK may regulate the expression of GST (Glutathione S-transferase) genes. RESULTS: The expression of STK was rapidly induced by ABA. STK was highest expressed in the stem at the heading stage. STK was localized at the plasma membrane. Overexpression of STK in rice increased tolerance to salt stress and oxidative stress by increasing ROS scavenging ability and ABA sensitivity. In contrast, CRISPR/Cas9-mediated knockout of STK increased the sensitivity of rice to salt stress and oxidative stress. Transcriptome sequencing analysis suggested that STK increased the expression of GST genes (LOC_Os03g17480, LOC_Os10g38140 and LOC_Os10g38710) under salt stress. Reverse transcription quantitative PCR (RT-qPCR) suggested that four stress-related genes may be regulated by STK including OsABAR1, Os3BGlu6, OSBZ8 and OsSIK1. CONCLUSIONS: These findings suggest that STK plays a positive regulatory role in salt stress tolerance by inducing antioxidant defense and associated with the ABA signaling pathway in rice.

4.
Plant Biotechnol J ; 20(5): 876-885, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34890109

RESUMEN

Rice blast and bacterial blight represent two of major diseases having devastating impact on the yield of rice in most rice-growing countries. Developments of resistant cultivars are the most economic and effective strategy to control these diseases. Here, we used CRISPR/Cas9-mediated gene editing to rapidly install mutations in three known broad-spectrum blast-resistant genes, Bsr-d1, Pi21 and ERF922, in an indica thermosensitive genic male sterile (TGMS) rice line Longke638S (LK638S). We obtained transgene-free homozygous single or triple mutants in T1 generations. While all single and triple mutants showed increased resistance to rice blast compared with wild type, the erf922 mutants displayed the strongest blast resistance similar with triple mutants. Surprisingly, we found that Pi21 or ERF922 single mutants conferred enhanced resistance to most of tested bacterial blight. Both resistances in mutants were attribute to the up-regulation of SA- and JA-pathway associated genes. Moreover, phenotypic analysis of these single mutants in paddy fields revealed that there were no trade-offs between resistances and main agricultural traits. Together, our study provides a rapid and effective way to generate rice varieties with resistance to both rice blast and bacterial blight.


Asunto(s)
Resistencia a la Enfermedad , Oryza , Sistemas CRISPR-Cas/genética , Resistencia a la Enfermedad/genética , Edición Génica , Oryza/genética , Oryza/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología
5.
Vet Res ; 52(1): 48, 2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741064

RESUMEN

Iron is essential for most bacteria to survive, but excessive iron leads to damage by the Fenton reaction. Therefore, the concentration of intracellular free iron must be strictly controlled in bacteria. Riemerella anatipestifer (R. anatipestifer), a Gram-negative bacterium, encodes the iron uptake system. However, the iron homeostasis mechanism remains largely unknown. In this study, it was shown that compared with the wild type R. anatipestifer CH-1, R. anatipestifer CH-1Δfur was more sensitive to streptonigrin, and this effect was alleviated when the bacteria were cultured in iron-depleted medium, suggesting that the fur mutant led to excess iron accumulation inside cells. Similarly, compared with R. anatipestifer CH-1∆recA, R. anatipestifer CH-1∆recAΔfur was more sensitive to H2O2-induced oxidative stress when the bacteria were grown in iron-rich medium rather than iron-depleted medium. Accordingly, it was shown that R. anatipestifer CH-1∆recAΔfur produced more intracellular ROS than R. anatipestifer CH-1∆recA in iron-rich medium. Electrophoretic mobility shift assays showed that R. anatipestifer CH-1 Fur suppressed the transcription of putative iron uptake genes through binding to their promoter regions. Finally, it was shown that compared with the wild type, R. anatipestifer CH-1Δfur was significantly attenuated in ducklings and that the colonization ability of R. anatipestifer CH-1Δfur in various tissues or organs was decreased. All these results suggested that Fur is important for iron homeostasis in R. anatipestifer and its pathogenic mechanism.


Asunto(s)
Hierro/metabolismo , Estrés Oxidativo , Riemerella/genética , Proteínas Bacterianas , Riemerella/metabolismo , Riemerella/patogenicidad , Virulencia
6.
Neuropsychiatr Dis Treat ; 16: 1473-1482, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32606700

RESUMEN

PURPOSE: Impairments in intra- and inter-hemispheric information transfer circuits have been reported in patients with major depressive disorder (MDD). However, the specific anomalous connection (intra- and/or inter-hemispheric) and hemisphere (left and/or right) in which this connection plays a more dominant role in the pathogenic mechanism underlying MDD are still poorly understood. PATIENTS AND METHODS: Structural magnetic resonance imaging and resting-state functional magnetic resonance imaging were performed in 33 patients with MDD and 33 healthy controls. The intra- and inter-hemispheric functional connectivity (FC) strength in the default mode network areas and volume of the callosal subregions were computed using independent samples t-tests. The partial correlations between the volumes and FCs were also computed. RESULTS: The patients with MDD had smaller volumes in the genu of the corpus callosum than the controls. The intrahemispheric FCs of the bilateral posterior cingulate gyrus, left precuneus, left medial superior frontal gyrus, left medial orbitofrontal gyrus, left angular gyrus and left middle temporal gyrus, and interhemispheric FCs of the bilateral posterior cingulate gyrus in the patients with MDD were lower than those in the controls. Moreover, the intrahemispheric FCs of the precuneus and interhemispheric FCs of middle frontal gyrus, orbital middle frontal gyrus, and anterior cingulate gyrus in the patients with MDD showed right-lateralized asymmetry, which were opposite from the asymmetry patterns observed in the controls. The functional asymmetry of the anterior cingulate gyrus was correlated with the volume of the genu of the corpus callosum and disease duration. CONCLUSION: These findings provide robust evidence that intra- and inter-hemispheric disconnections are involved in MDD, and that functional disruptions in the left hemisphere may be more relevant to the pathophysiology of MDD. Furthermore, imbalanced interhemispheric exchanges may contribute to the anatomical deficits in the corpus callosum in patients with MDD.

7.
Plant Mol Biol ; 101(4-5): 403-414, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31420780

RESUMEN

Anther dehiscence, one of the essential steps in pollination and double fertilization, is regulated by a complex signaling pathway encompassing hormones and environmental factors. However, key components underlying the signaling pathway that regulate anther dehiscence remain largely elusive. Here, we isolated a rice mutant anther dehiscence defected 1 (Osadd1) that exhibited defects in anther dehiscence and glume open. Map-based cloning revealed that OsADD1 encoded a GARP (Golden2, ARR-B and Psr1) transcription factor. Sequence analysis showed that a single base deletion in Osadd1 mutant resulted in pre-termination of the GARP domain. OsADD1 was constitutively expressed in various tissues, with more abundance in the panicles. The major genes associated with anther dehiscence were affected in the Osadd1 mutant, and the expression level of the cellulose synthase-like D sub-family 4 (OsCSLD4) was significantly decreased. We demonstrate that OsADD1 regulated the expression of OsCSLD4 by binding to its promoter, and affects rice anther dehiscence.


Asunto(s)
Flores/fisiología , Oryza/fisiología , Proteínas de Plantas/fisiología , Factores de Transcripción/fisiología , Clonación Molecular , Flores/ultraestructura , Regulación de la Expresión Génica de las Plantas , Oryza/crecimiento & desarrollo , Oryza/ultraestructura , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
8.
Neuroimage Clin ; 21: 101614, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30528958

RESUMEN

BACKGROUND: Numerous cognitive and emotional functions are executed asymmetrically between the left and right hemispheres. Right hemisphere hyperactivity/left hemisphere hypoactivity often appears to be a feature in neuroimaging studies of depression. However, few studies have evaluated abnormalities in structural asymmetry in untreated patients with major depressive disorder (MDD). METHODS: In this study, 3-dimensional high-resolution structural magnetic resonance images were acquired from 35 treatment-naïve patients with MDD (mean age = 28.9 years, 22 females) and 35 normal controls. The asymmetry index in cortical thickness and subcortical volume were calculated based on an automated surface-based technique. RESULTS: Abnormalities in structural asymmetry in patients with MDD were mainly located in the cortical-striatal-pallidal-thalamic circuit, including the superior frontal cortex, rostral middle frontal cortex, caudal middle frontal cortex, nucleus accumbens, pallidum and thalamus. No significant correlation was observed between symptom severity and asymmetric measurements. CONCLUSION: These findings provide further evidence for the altered morphological interhemispheric imbalances in depression and these alterations were independent of depressive symptom severity, suggesting that cerebral asymmetry could be an appropriate indicator of morphological variations in mental disease.


Asunto(s)
Encéfalo/patología , Trastorno Depresivo Mayor/patología , Lateralidad Funcional , Adulto , Encéfalo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Trastorno Depresivo Mayor/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino
9.
Front Psychiatry ; 9: 323, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30079037

RESUMEN

Background: Impairments in cognitive and emotional processing are a characteristic of major depressive disorder (MDD), and the dorsolateral prefrontal cortex (DLPFC) and amygdala are involved in these processes. However, the structural covariance between these two areas in patients with MDD has not been examined. Whether anatomical patterns are further damaged or compensated in untreated multiple-episode MDD compared to those in first-episode MDD is unclear. Methods: Structural magnetic resonance imaging was performed in 35 treatment-naïve, currently depressed patients with MDD and 35 age-, sex-, and education-matched controls. The cortical thickness and subcortical volume were calculated using FreeSurfer software. Patients were divided into two subgroups based on the previous number of episodes. Results: Regional abnormalities in patients with MDD were primarily observed in the frontal-limbic circuits. The negative structural association between the left DLPFC and left amygdala and the positive structural association between the bilateral DLPFC observed in controls were absent in patients with MDD. The medial orbitofrontal cortex and posterior cingulate cortex were thicker in patients with multiple-episode MDD than in patients with first-episode MDD and were positively correlated with disorder duration. No structural alterations were correlated with symptom severity. Conclusions: These findings may provide structural evidence for deficits in functional networks in MDD and supports an underlying structural mechanism of dysfunction involving top-down or bottom-up processes. Morphological abnormalities in the medial orbitofrontal cortex and posterior cingulate cortex may be critical for the pathophysiological progression of multiple-episode MDD.

10.
Nano Lett ; 17(8): 4976-4981, 2017 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-28671471

RESUMEN

With the growing adoption of interconnected electronic devices in consumer and industrial applications, there is an increasing demand for robust security protocols when transmitting and receiving sensitive data. Toward this end, hardware true random number generators (TRNGs), commonly used to create encryption keys, offer significant advantages over software pseudorandom number generators. However, the vast network of devices and sensors envisioned for the "Internet of Things" will require small, low-cost, and mechanically flexible TRNGs with low computational complexity. These rigorous constraints position solution-processed semiconducting single-walled carbon nanotubes (SWCNTs) as leading candidates for next-generation security devices. Here, we demonstrate the first TRNG using static random access memory (SRAM) cells based on solution-processed SWCNTs that digitize thermal noise to generate random bits. This bit generation strategy can be readily implemented in hardware with minimal transistor and computational overhead, resulting in an output stream that passes standardized statistical tests for randomness. By using solution-processed semiconducting SWCNTs in a low-power, complementary architecture to achieve TRNG, we demonstrate a promising approach for improving the security of printable and flexible electronics.

11.
Cell Biochem Biophys ; 70(3): 1799-802, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25062968

RESUMEN

The objective of the study was to explore the effects of olanzapine-fluoxetine combination (OFC) treatment of major depressive disorders on the quality of life in the acute treatment period. Methods were prospective and observational design. One hundred and three patients of major depressive disorders were observed. One group of 53 patients received OFC treatment (OFC group); the other group of 50 patients received the treatment of duloxetine (duloxetine group). Two groups were needed to be observed 8 weeks. Observed indicators were Hamilton Depression Rating Scale for Depression (HAMD-24) and four factor scores: the slow, sleep disorders, anxiety/somatization, and hopelessness, Clinical Global Impression-Severity of Illness (CGI-S), WHO quality of life scale (WHOQOL-BREF), and sub-rate measurements. HAMD-24 and four factor scores observation time were assessed before and after treatment; 1, 2, 4, 8 weeks, WHOQOL-BREF score, and sub-time measurements were assessed before treatment and 8 weeks after treatment. HAMD-24 scores of OFC patients in the first week were significantly lower than those of the duloxetine group. The sleep factor scores of OFC patients were significantly lower than those of the duloxetine group in 4 and 8 weeks. By the end of 8 weeks, OFC group was rated significantly lower than the duloxetine group in the physical area. In the acute treatment period, OFC treatment effected faster than the single duloxetine in patients with major depressive disorders. OFC effected within 1 week and was better than the single duloxetine in improving the sleep and physical conditions.


Asunto(s)
Benzodiazepinas/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Fluoxetina/uso terapéutico , Calidad de Vida , Adulto , Benzodiazepinas/efectos adversos , Trastorno Depresivo Mayor/psicología , Esquema de Medicación , Combinación de Medicamentos , Clorhidrato de Duloxetina , Femenino , Fluoxetina/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Trastornos del Sueño-Vigilia/etiología , Trastornos Somatomorfos/etiología , Tiofenos/efectos adversos , Tiofenos/uso terapéutico
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