RESUMEN
With the gradual expansion of the application of organic electromechanical synthesis in the field of energetic materials, it is necessary to explore deeply the mechanisms behind the organic electromechanical oxidation of energetic materials in order to develop efficient electrocatalysts. Electrochemical synthesis of 5,5'-azotetrazolate (ZT) salts is not only environmentally friendly and efficient but also can replace oxygen evolution reaction (OER) combined with hydrogen production, significantly reducing the battery voltage of overall water splitting (OWS) and achieving low energy consumption hydrogen production. Here, we prepared the Co-modified nickel-based oxide electrodes (Ni3-xCoO4/carbon cloth (CC), x = 1, 2) as a medium to reveal the oxidative coupling mechanism of 5-aminotetrazole (5-AT). Experimental and theoretical calculations verified that Ni-catalyzed oxidative coupling of 5-AT is a proton-coupled electron transfer (PCET) process, including electron transfer of electrocatalytic intermediates (Ni2+-O + OH- = Ni3+-O(OH) + e-) and spontaneous dehydrogenation process (Ni3+-O(OH) + X-H = Ni2+-O + Xâ¢). The Ni3+-O(OH) is an extremely fast nonreducing electron transfer center that serves as a chemical oxidant to directly abstract hydrogen atoms from the 5-AT. Simultaneously, the synergistic effect of Co doping on the electric cloud around Ni causes the upshift of the d-band centers, which is conducive to the easier adsorption of OH*, forming the generation of active intermediate Ni3+-O(OH). Thus, Ni2CoO4/CC has higher Faraday efficiency (FE) and yield for the oxidation reaction of 5-AT, with a yield of approximately 72.3% after electrolysis at 1.7 V vs reversible hydrogen electrode (RHE).
RESUMEN
Background: The co-occurrence of depression and anxiety among adolescents is typically associated with suicide ideation. Aims: The study aimed to investigate the symptom-level relationship between suicide ideation and the comorbidity of depression and anxiety. Methods: 1501 adolescents aged 12-19 years were assessed using the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder Scale, and 716 adolescents who scored ≥5 on both scales were selected as participants. Network analysis was used to identify the network structure of depressive symptoms and anxiety symptoms. Participants were categorised into either the suicide ideation or non-suicide ideation groups based on their scoring on the suicide-related item in PHQ-9. A comparison was made between the depression-anxiety symptom networks of the two groups. Results: 'Restlessness', 'sad mood' and 'trouble relaxing' were the most prominent central symptoms in the depression-anxiety symptom network, and 'restlessness', 'nervousness' and 'reduced movement' were the bridge symptoms in this network. 'Sad mood' was found to be directly related to 'suicide ideation' with the highest variance. The network structure was significantly different in properties between the suicide ideation group and the non-suicide ideation group, with 'restlessness' and 'sad mood' exhibiting significantly higher influence in the network of the suicide ideation group than that in the non-suicide ideation group. Conclusion: Restlessness and sad mood could be targeted for the intervention of depression-anxiety symptoms among adolescents with suicide ideation.
RESUMEN
BACKGROUND: A disruption of the kynurenine (KYN) pathway may exist in major depressive disorder (MDD). However, the changing pattern of the KYN pathway across the different disease states in MDD is unclear. Herein, we performed a meta-analysis to examine the differences in KYN metabolites between patients in the current episode of MDD (cMDD) and patients in remission (rMDD), as well as the changes after treatments. METHODS: Literature was systematically searched from electronic databases, from inception up to September 2022. Random-effect models were used to quantify the differences in KYN metabolites between patients with MDD across acute depressive episode and remission phases, as well as the changes after treatments. RESULTS: Fifty-one studies involving 7056 participants were included. Tryptophan (TRP), KYN, kynurenic acid (KYNA), KYNA/quinolinic acid (QA), KYNA/3-hydroxykynurenine (3-HK), and KYNA/KYN were significantly lower, while KYN/TRP was significantly higher in patients with cMDD. Moreover, these effect sizes were generally larger in medication-free patients. No significant differences were found between patients with rMDD and HCs. Additionally, KYNA was found negatively correlated with depression severity and significantly increased after treatments, while the alteration was not found in QA. LIMITATIONS: The number of included studies of patients with rMDD and longitudinal studies investigating the change of the KYN metabolites after treatment with antidepressants was limited. In addition, the heterogeneity across included studies was relatively high. CONCLUSIONS: These findings showed a comprehensive image of the unique dysfunction pattern of the KYN pathway across different MDD states and highlighted KYNA as a potentially sensitive biomarker of MDD.
Asunto(s)
Trastorno Depresivo Mayor , Quinurenina , Humanos , Quinurenina/metabolismo , Triptófano/metabolismo , Depresión/metabolismo , Biomarcadores , Ácido Quinurénico/metabolismo , Ácido Quinolínico/metabolismoRESUMEN
Agrobacterium rhizogenes-mediated hairy root culture offer a promising approach for gene function analysis and production of plant secondary metabolites. Here, we obtained red litchi hairy roots using A. rhizogenes-mediated LcMYB1 transformation. Using high performance liquid chromatography, the main anthocyanins in the red hairy roots were determined to be cyanidin 3-rutinoside and cyanidin 3-glucoside. A total of 164 metabolites were significantly upregulated or downregulated in the red hairy roots, which were mostly involved in flavone and flavonol pathway, and flavonoid pathway. The transcriptome analysis revealed 472 differentially expressed genes (DEGs). Up-regulated genes were considerably enriched in anthocyanin, flavone and flavonol biosynthesis. Integrative metabolite profiling and transcriptome analyses showed that LcF3'H, LcUFGT1, and LcGST4 were key structural genes in anthocyanin biosynthesis. However, the expression of Cinnamyl-alcohol dehydrogenase (CAD) and Peroxidase (POD) leading to the production of lignin were significantly down-regulated, suggesting flavonoids and lignin compete with each other in the phenylpropanoid pathway. A total of 52 DEGs were identified as transcription factors. Correlation analysis showed that 8 transcription factors were positively correlated with LcUFGT1, and LcGST4, involving in anthocyanin biosynthesis. These findings clarify the molecular mechanisms of LcMYB1 regulating anthocyanin accumulation in litchi hairy roots.
Asunto(s)
Flavonas , Litchi , Antocianinas/metabolismo , Litchi/genética , Litchi/metabolismo , Lignina/metabolismo , Perfilación de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Metaboloma , Transcriptoma/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
Introduction: This study aimed to investigate the psychometric properties of the Affective Lability Scale-short form (ALS-SF) among Chinese patients with mood disorders, and to compare ALS-SF subscale scores between patients with major depressive disorder (MDD) and patients with bipolar disorder (BD) depression. Methods: A total of 344 patients with mood disorders were included in our study. Participants were measured through a set of questionnaires including the Chinese version of ALS-SF, Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder 7-item (GAD-7), and NEO-Five Factor Inventory (NEO-FFI). Exploratory factor analysis and confirmatory factor analysis were applied to examine the psychometric properties of ALS-SF. Besides, correlation and regression analyses were performed to explore the relationship between affective lability and depression, anxiety, and neuroticism. Independent samples t-tests were used to compare the subscale scores of ALS-SF between the MDD and BD depression groups. Results: Results of factor analysis indicated that the model of ALS-SF was consistent with ALS-SF. The ALS-SF showed a solid validity and high internal consistency (Cronbach's alpha = 0.861). In addition, each subscale of ALS-SF was significantly correlated with PHQ-9, GAD-7, and NEO-FFI neuroticism subscale, except for the anger subscale showed no significant correlation with PHQ-9. Besides, the depression/elation and anger factor scores in patients with BD depression were higher than in patients with MDD. Conclusion: Our study suggests that the Chinese version of ALS-SF has good reliability and validity for measuring affective lability in Chinese patients with mood disorders. Assessing affective lability would assist clinicians to distinguish between MDD and BP depression and may decrease the risks of misdiagnosis.
RESUMEN
Anthocyanins are health-promoting compounds with strong antioxidant properties that play important roles in disease prevention. Litchi chinensis Sonn. is a well-known and economically significant fruit due to its appealing appearance and nutritional value. The mature pericarp of litchi is rich in anthocyanins, whereas the aril (flesh) has an extremely low anthocyanin content. However, the mechanism of anthocyanin differential accumulation in litchi pericarp and aril remained unknown. Here, metabolome and transcriptome analysis were performed to unveil the cause of the deficiency of anthocyanin biosynthesis in litchi aril. Numerous anthocyanin biosynthesis-related metabolites and their derivatives were found in the aril, and the levels of rutin and (-)-epicatechin in the aril were comparable to those found in the pericarp, while anthocyanin levels were negligible. This suggests that the biosynthetic pathway from phenylalanine to cyanidin was present but that a block in cyanidin glycosylation could result in extremely low anthocyanin accumulation in the aril. Furthermore, 54 candidate genes were screened using weighted gene co-expression network analysis (WGCNA), and 9 genes (LcUFGT1, LcGST1, LcMYB1, LcSGR, LcCYP75B1, LcMATE, LcTPP, LcSWEET10, and LcERF61) might play a significant role in regulating anthocyanin biosynthesis. The dual-luciferase reporter (DLR) assay revealed that LcMYB1 strongly activated the promoters of LcUFGT1, LcGST4, and LcSWEET10. The results imply that LcMYB1 is the primary qualitative gene responsible for the deficiency of anthocyanin biosynthesis in litchi aril, which was confirmed by a transient transformation assay. Our findings shed light on the molecular mechanisms underlying tissue-specific anthocyanin accumulation and will help developing new red-fleshed litchi germplasm.
Asunto(s)
Antocianinas , Litchi , Antocianinas/metabolismo , Litchi/genética , Litchi/metabolismo , Frutas/genética , Perfilación de la Expresión Génica , Metaboloma , Transcriptoma , Regulación de la Expresión Génica de las PlantasRESUMEN
Lithium-based nitrogen-rich complexes are important research objects in the field of high-energy materials. However, the weak coordination abilities of lithium ions relative to those of other metal ions with greater atomic numbers have hindered their applications in the field of nitrogen-rich complexes. Herein, we successfully prepared novel lithium-based nitrogen-rich complexes (N2H5-2AZTO-Li and NH3OH-2AZTO-Li) by exploiting the structural properties of 1-hydroxytetrazolium-5-hydrazine (HAZTO). Both N2H5-2AZTO-Li and NH3OH-2AZTO-Li were found to exhibit physicochemical parameters (including the density, stability, and energetic properties) that were intermediate between those of the simple ionic compounds (3 and 4) and the complexes (5) that formed them, enabling a favorable balance between high energy, high stability, and environmental friendliness (for N2H5-2AZTO-Li: detonation velocity (D) = 9005 m s-1, detonation pressure (P) = 35.5 GPa, decomposition temperature (Tdec) = 238.1 °C, impact sensitivity (IS) = 24 J, friction sensitivity (FS) = 210 N, and detonation product (DP) (CO) < 2%; for NH3OH-2AZTO-Li: D = 9028 m s-1, P = 35.7 GPa, Tdec = 211.2 °C, IS = 20 J, FS = 180 N, and DP (CO) < 2%). This study transcends the conventional structural forms of nitrogen-rich complexes, opening new horizons for the design of novel insensitive energetic materials.
RESUMEN
Objective: Previous studies on the reliability and validity of the Affective Lability Scale short-form (ALS-SF) have only been evaluated in adults, which may not be able to generalize to the adolescent population. We aimed to examine the factor structure, the reliability and validity of ALS-SF among Chinese adolescents and construct an adolescent form of ALS (ALS-AF). Methods: A total of 1,439 middle school students were investigated with a broad survey including ALS-SF, Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder 7-item (GAD-7), Connor-Davidson Resilience Scale 10-item (CD-RISC-10) and non-suicidal self-injury (NSSI) behavior self-report. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted to investigate the structural validity of ALS-SF and construct ALS-AF. Cronbach's α was used to assess the internal consistency and reliability of the scale. Factor loading, Average Variance Extracted (AVE) and Composite Reliability (CR) were applied to measure the convergent validity and divergent validity. Besides, Correlation and regression analyses were used to explore the relationship between affective lability and depression, anxiety, NSSI and resilience. Results: Factor analysis failed to support the original three-factor model of 18-item ALS-SF and confirmed the three-factor model of 15-item ALS-AF. The ALS-AF showed good internal consistency as well as strong convergent and discriminative validity. Besides, ALS-AF was positively correlated with PHQ-9, GAD-7 and self-harm, and was negatively associated with resilience. Conclusion: Our study shows that the ALS-AF has good reliability and validity for testing affective lability in Chinese adolescents.
RESUMEN
The development of catalysts which can substitute expensive metals to efficiently split water is currently a hot research topic. Here, a multi-layered NF/NiCo2O4/Co3S4 nanocomposite was prepared on 3D porous nickel foam by hydrothermal and annealing processes. The electrode is a multi-layered, highly conductive and high specific surface area network without a binder, which facilitates electron transport and exposure of active sites, enhances full contact of the electrolyte/electrode interface, and accelerates H2 and O2 diffusion during water electrolysis. As expected, NF/NiCo2O4/Co3S4 exhibits surprising electrocatalytic activity, and only required 71 and 170 mV to reach 10 mA cm-2 in the hydrogen and oxygen evolution reactions, respectively, and exhibited stability up to 36 h. This strategy provides an efficient, durable, and low-cost bifunctional catalyst.
RESUMEN
It is of utmost importance to explore bifunctional electrocatalysts for water splitting. Herein, unique ZnCo2O4-CoOOH heterostructured ultrathin nanosheets on Ni foam are reported that combines a two-step hydrothermal method. This catalyst exhibits excellent catalytic performances to achieve a current density of 10 mA cm-2 with an ultralow overpotential of 115 mV for HER, attaining an overpotential of 238 mV at 20 mA cm-2 for OER. Remarkably, ZnCo2O4-CoOOH/Ni shows a voltage of 1.494 V to drive a current density of 10 mA cm-2. Such performances are due to the inter-penetrative pores present in the ultrathin nanosheets that provide large surface areas and expose massive active sites to enhance activities. In addition, the unique nanosheet structure and the 3D Ni foam substrate possess large specific surface areas, which can facilitate mass diffusion. This excellent performance is ascribed to the ZnCo2O4-CoOOH heterostructure that manipulates strong synergy to improve the electrochemical activity. This study offers new insight on an innovative approach for the exploitation of effective bifunctional electrocatalysts with a heterostructure.
RESUMEN
High-efficiency explosives that combine high stability and excellent energy performance are one of the key directions of energetic materials research. In this study, a novel monocyclic hydroxytetrazole derivative (3) with high stability was prepared, and a series of insensitive energetic ionic salts were derived from it. Benefiting from their outstanding performance in terms of density, 3D hydrogen bonding and π-electron interactions, these salts are excellent in both detonation performance (D = 8709 to 9314 m s-1 and P = 29.9 to 35.6 GPa) and thermal stability (Td = 193.0-232.2 °C). The hydrazine salt (2) exhibits high detonation properties (D = 9314 m s-1 and P = 35.6 GPa), due to its high density (ρ = 1.71 g cm-3) and high heat of formation (ΔfH = 563.2 kJ mol-1 = 3.19 kJ g-1). In addition, the high thermal stability (Td = 232.0 °C) and low mechanical sensitivity (IS = 30 J and FS = 360 N) of 2 are also unmatched by HMX and TKX-50. These improved properties demonstrate the great promise of 2 as an insensitive high-energy explosive.
RESUMEN
BACKGROUND: Litchi chinensis Sonn. is an economically important fruit tree in tropical and subtropical regions. However, litchi functional genomics is severely hindered due to its recalcitrance to regeneration and stable transformation. Agrobacterium rhizogenes-mediated hairy root transgenic system provide an alternative to study functional genomics in woody plants. However, the hairy root transgenic system has not been established in litchi. RESULTS: In this study, we report a rapid and highly efficient A. rhizogenes-mediated co-transformation system in L. chinensis using Green Fluorescent Protein (GFP) gene as a marker. Both leaf discs and stem segments of L. chinensis cv. 'Fenhongguiwei' seedlings were able to induce transgenic hairy roots. The optimal procedure involved the use of stem segments as explants, infection by A. rhizogenes strain MSU440 at optical density (OD600) of 0.7 for 10 min and co-cultivation for 3 days, with a co-transformation efficiency of 9.33%. Furthermore, the hairy root transgenic system was successfully used to validate the function of the key anthocyanin regulatory gene LcMYB1 in litchi. Over-expression of LcMYB1 produced red hairy roots, which accumulated higher contents of anthocyanins, proanthocyanins, and flavonols. Additionally, the genes involving in the flavonoid pathway were strongly activated in the red hairy roots. CONCLUSION: We first established a rapid and efficient transformation system for the study of gene function in hairy roots of litchi using A. rhizogenes strain MSU440 by optimizing parameters. This hairy root transgenic system was effective for gene function analysis in litchi using the key anthocyanin regulator gene LcMYB1 as an example.
RESUMEN
Sampling is a widely used graph reduction technique to accelerate graph computations and simplify graph visualizations. By comprehensively analyzing the literature on graph sampling, we assume that existing algorithms cannot effectively preserve minority structures that are rare and small in a graph but are very important in graph analysis. In this work, we initially conduct a pilot user study to investigate representative minority structures that are most appealing to human viewers. We then perform an experimental study to evaluate the performance of existing graph sampling algorithms regarding minority structure preservation. Results confirm our assumption and suggest key points for designing a new graph sampling approach named mino-centric graph sampling (MCGS). In this approach, a triangle-based algorithm and a cut-point-based algorithm are proposed to efficiently identify minority structures. A set of importance assessment criteria are designed to guide the preservation of important minority structures. Three optimization objectives are introduced into a greedy strategy to balance the preservation between minority and majority structures and suppress the generation of new minority structures. A series of experiments and case studies are conducted to evaluate the effectiveness of the proposed MCGS.
RESUMEN
BACKGROUND: SWEETs (Sugar Will Eventually be Exported transporters) function as sugar efflux transporters that perform diverse physiological functions, including phloem loading, nectar secretion, seed filling, and pathogen nutrition. The SWEET gene family has been identified and characterized in a number of plant species, but little is known about in Litchi chinensis, which is an important evergreen fruit crop. RESULTS: In this study, 16 LcSWEET genes were identified and nominated according to its homologous genes in Arabidopsis and grapevine. Multiple sequence alignment showed that the 7 alpha-helical transmembrane domains (7-TMs) were basically conserved in LcSWEETs. The LcSWEETs were divided into four clades (Clade I to Clade IV) by phylogenetic tree analysis. A total of 8 predicted motifs were detected in the litchi LcSWEET genes. The 16 LcSWEET genes were unevenly distributed in 9 chromosomes and there was one pairs of segmental duplicated events by synteny analysis. The expression patterns of the 16 LcSWEET genes showed higher expression levels in reproductive organs. The temporal and spatial expression patterns of LcSWEET2a and LcSWEET3b indicated they play central roles during early seed development. CONCLUSIONS: The litchi genome contained 16 SWEET genes, and most of the genes were expressed in different tissues. Gene expression suggested that LcSWEETs played important roles in the growth and development of litchi fruits. Genes that regulate early seed development were preliminarily identified. This work provides a comprehensive understanding of the SWEET gene family in litchi, laying a strong foundation for further functional studies of LcSWEET genes and improvement of litchi fruits.
Asunto(s)
Litchi/genética , Proteínas de Transporte de Monosacáridos/genética , Proteínas de Plantas/genética , Semillas/crecimiento & desarrollo , Cromosomas de las Plantas , Secuencia Conservada , ADN de Plantas , Perfilación de la Expresión Génica , Genes de Plantas , Filogenia , Semillas/genética , Alineación de Secuencia , SinteníaRESUMEN
In this study, the porous composite films of carboxymethyl chitosan/alginate/tranexamic acid were fabricated, with calcium chloride as the crosslinking agent and glycerin as a plasticizer. The composite films were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The properties of the composite films, including water absorption, air permeability, and cumulative release rate, were tested. In addition, their hemostatic performance was evaluated. The results showed that the appearance of the films with good adhesion was smooth and porous. FTIR showed that chemical crosslinking between carboxymethyl chitosan and sodium alginate was successful. The excellent cumulative release of tranexamic acid in the composite films (60â»80%) gives the films a significant procoagulant effect. This has good prospects for the development of medical hemostasis materials.
RESUMEN
During litchi (Litchi chinensis Sonn.) fruit ripening, two major physiological changes, degreening (Chl degradation) and pigmentation (anthocyanin biosynthesis), are visually apparent. However, the specific factor triggering this important transition is still unclear. In the present study, we found that endogenous ABA content increased sharply when Chl breakdown was initiated and the ABA level peaked just before the onset of anthocyanin accumulation, suggesting that ABA plays an important role during litchi fruit pigmentation. We characterized three ABSCISIC ACID RESPONSE ELEMENT-BINDING FACTORs (LcABF1/2/3) belonging to group A of the basic leucine zipper (bZIP) transcription factors previously shown to be involved in ABA signaling under abiotic stress. LcABF1 transcripts increased at the onset of Chl degradation, and the expression of LcABF3 accumulated in parallel with anthocyanin biosynthesis. In addition, dual luciferase and yeast one-hybrid assays indicated that LcABF1/2 recognized ABA-responsive elements in the promoter region of Chl degradation-related genes (PAO and SGR), while LcABF2/3 bound the promoter region of LcMYB1 and anthocyanin biosynthesis-related structural genes. Indeed, Nicotiana benthamiana leaves transiently expressing LcABF1/2 showed a senescence phenomenon with Chl degradation, and LcABF3 overexpression increased the accumulation of anthocyanin via activation of LcMYB1, which is the key determinant of anthocyanin biosynthesis. These data indicate that LcABF1/2/3 are important transcriptional regulators of ABA-dependent litchi fruit ripening involved in both Chl degradation and anthocyanin biosynthesis.
Asunto(s)
Antocianinas/biosíntesis , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/fisiología , Clorofila/metabolismo , Frutas/crecimiento & desarrollo , Litchi/metabolismo , Proteínas de Plantas/fisiología , Ácido Abscísico/metabolismo , Ácido Abscísico/fisiología , Frutas/metabolismo , Regulación de la Expresión Génica Arqueal , Genes de Plantas/fisiología , Litchi/genética , Litchi/crecimiento & desarrollo , Filogenia , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/fisiología , Plantas Modificadas Genéticamente , Alineación de Secuencia , NicotianaRESUMEN
Sucrose phosphate synthase (SPS, EC 2.4.1.14) is a key enzyme that regulates sucrose biosynthesis in plants. SPS is encoded by different gene families which display differential expression patterns and functional divergence. Genome-wide identification and expression analyses of SPS gene families have been performed in Arabidopsis, rice, and sugarcane, but a comprehensive analysis of the SPS gene family in Litchi chinensis Sonn. has not yet been reported. In the current study, four SPS gene (LcSPS1, LcSPS2, LcSPS3, and LcSPS4) were isolated from litchi. The genomic organization analysis indicated the four litchi SPS genes have very similar exon-intron structures. Phylogenetic tree showed LcSPS1-4 were grouped into different SPS families (LcSPS1 and LcSPS2 in A family, LcSPS3 in B family, and LcSPS4 in C family). LcSPS1 and LcSPS4 were strongly expressed in the flowers, while LcSPS3 most expressed in mature leaves. RT-qPCR results showed that LcSPS genes expressed differentially during aril development between cultivars with different hexose/sucrose ratios. A higher level of expression of LcSPS genes was detected in Wuheli, which accumulates higher sucrose in the aril at mature. The tissue- and developmental stage-specific expression of LcSPS1-4 genes uncovered in this study increase our understanding of the important roles played by these genes in litchi fruits.