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1.
Front Psychiatry ; 15: 1383992, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962062

RESUMO

Objective: To investigate the prevalence and associated factors of suicidal ideation and suicide attempts among adolescent and young adults in China from December 14, 2022 to February 28, 2023, when COVID-19 restrictions were lifted. Methods: Students in middle and high schools and colleges and universities in the province of Sichuan, China were asked to complete on-line cross-sectional surveys. Information was collected about sociodemographics, experiences related to the COVID-19 pandemic, suicidal ideation and suicide attempts. Participants also filled out the Patient Health Questionnaire-9, the Generalized Anxiety Disorder-7 and the Social Support Rate Scale surveys. Factors associated with suicidal ideation or suicide attempts were explored using logistic regression. Results: Of the 82,873 respondents (aged 12 to 24 years), 21,292 (25.7%) reported having thought of suicide at least once in their lifetime, 10,382 (12.5%) reported having thought about suicide within the previous 12 months, and 1,123 (1.4%) reported having attempted it within the previous 12 months. Risk of lifetime suicidal ideation was higher among middle school students than among older students. Risk of suicidal ideation and risk of suicide attempts correlated directly with severity of symptoms of depression and anxiety, and inversely with level of social support. Greater risk of suicidal ideation and suicidal attempts was associated with: being female, living in an urban environment, attending a boarding school, currently being in love, having parents who divorced or remarried, having parents who exhibit non-authoritative parenting behavior, having higher family income, having been COVID-19 infected, having been quarantined for a long time, and being dissatisfied with one's education. Conclusions: Suicidal ideation and suicide attempts remain prevalent among young people in China. The potential associated factors identified in our study may be useful for targeting appropriate psychosocial interventions and developing mental health policies.

2.
J Colloid Interface Sci ; 674: 238-248, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38936080

RESUMO

The voltage decay of Li-rich layered oxide cathode materials results in the deterioration of cycling performance and continuous energy loss, which seriously hinders their application in the high-energy-density lithium-ion battery (LIB) market. However, the origin of the voltage decay mechanism remains controversial due to the complex influences of transition metal (TM) migration, oxygen release, indistinguishable surface/bulk reactions and the easy intra/inter-crystalline cracking during cycling. We investigated the direct cause of voltage decay in micrometer-scale single-crystal Li1.2Mn0.54Ni0.13Co0.13O2 (SC-LNCM) cathode materials by regulating the cut-off voltage. The redox of TM and O2- ions can be precisely controlled by setting different voltage windows, while the cracking can be restrained, and surface/bulk structural evaluation can be monitored because of the large single crystal size. The results show that the voltage decay of SC-LNCM is related to the combined effect of cation rearrangement and oxygen release. Maintaining the discharge cutoff voltage at 3 V or the charging cutoff voltage at 4.5 V effectively mitigates the voltage decay, which provides a solution for suppressing the voltage decay of Li-rich and Mn-based layered oxide cathode materials. Our work provides significant insights into the origin of the voltage decay mechanism and an easily achievable strategy to restrain the voltage decay for Li-rich and Mn-based cathode materials.

3.
Chem Sci ; 15(16): 5869-5896, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38665521

RESUMO

With the continuous development of laser technology and the increasing demand for lasers of different frequencies in the infrared (IR) spectrum, research on infrared nonlinear optical (NLO) crystals has garnered growing attention. Currently, the three main commercially available types of borate materials each have their drawbacks, which limit their applications in various areas. Rare-earth (RE)-based chalcogenide compounds, characterized by the unique f-electron configuration, strong positive charges, and high coordination numbers of RE cations, often exhibit distinctive optical responses. In the field of IR-NLO crystals, they have a research history spanning several decades, with increasing interest. However, there is currently no comprehensive review summarizing and analyzing these promising compounds. In this review, we categorize 85 representative examples out of more than 400 non-centrosymmetric (NCS) compounds into four classes based on the connection of different asymmetric building motifs: (1) RE-based chalcogenides containing tetrahedral motifs; (2) RE-based chalcogenides containing lone-pair-electron motifs; (3) RE-based chalcogenides containing [BS3] and [P2Q6] motifs; and (4) RE-based chalcohalides and oxychalcogenides. We provide detailed discussions on their synthesis methods, structures, optical properties, and structure-performance relationships. Finally, we present several favorable suggestions to further explore RE-based chalcogenide compounds. These suggestions aim to approach these compounds from a new perspective in the field of structural chemistry and potentially uncover hidden treasures within the extensive accumulation of previous research.

4.
Dalton Trans ; 53(18): 8011-8019, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38651951

RESUMO

Designing efficient, inexpensive, and stable photocatalysts to degrade organic pollutants and antibiotics has become an effective way for environmental remediation. In this work, we successfully performed in situ growth of CdS QDs on the surface of elliptical BiVO4 to try to show the advantage of the binary heterojuncted photocatalyst (BVO@CdS) for the photocatalytic degradation of tetracycline (TC). The In situ growth of CdS QDs can provide a large number of reactive sites and also generate a larger contact area with BiVO4. In addition, compared with mechanical composite materials, in situ growth can significantly reduce the energy barrier at the interface between BiVO4 and CdS, providing more channels for the separation and migration of photogenerated charge carriers, and further improving reaction activity. As a result, BVO@CdS-0.05 shows the best degradation efficiency, with a degradation rate of 88% after 30 min under visible light. The TC photodegradation follows a pseudo-second-order reaction with a dynamic constant of 0.472 min-1, which is 6.47 times that of pure BiVO4, 7.24 times that of pure CdS QDs and 2 times that of the mechanical composite. The degradation rate of BVO@CdS-0.05 decreases to 77.8% with a retention rate of 88.5% after four cycles, demonstrating excellent stability. Through liquid chromatography-mass spectrometry (LC-MS) analysis, two possible pathways for TC degradation are proposed. Through free radical capture experiments, electron spin resonance measurements, and photoelectrochemical comprehensive analysis, it is confirmed that BVO@CdS composites have constructed an efficient Z-scheme heterojunction via in situ growth, thereby highly enhancing the separation and transport efficiency of charge carriers.

6.
Inorg Chem ; 63(9): 4022-4027, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38391142

RESUMO

Noncentrosymmetric (NCS) oxychalcogenides have attracted great attention in recent years due to their immense potential as candidates for IR nonlinear-optical (NLO) applications. Despite notable advancements in this field, the discovery of oxychalcogenides with three-dimensional (3D) framework structures remains a formidable challenge. In this study, we report the discovery of the first hexanary oxychalcogenide, Ba10In2Mn11Si3O12S18, exhibiting second-order NLO activity, using a high-temperature solid-phase method. This compound showcases a novel structure type, featuring an uncommon NCS 3D [In2Mn11Si3O12S18]20- framework formed by vertex-sharing [(Mn/In)S6] octahedra, [(Mn/In)OS3] tetrahedra, and [SiO4] tetrahedra, with charge-balanced Ba2+ cations occupying the channels. Our study serves as a source of inspiration for researchers to further investigate the synthesis of novel NLO-active oxychalcogenides with 3D frameworks.

8.
J Affect Disord ; 350: 916-925, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244788

RESUMO

BACKGROUND: Which life satisfaction components could be a target of positive psychological interventions for longevity is largely unknown. We aimed to investigate association of the composite measure of life satisfaction and its individual components with mortality. METHODS: This cohort study included UK Biobank participants who responded to questions concerning five components of life satisfaction at baseline. We generated a composite score representing overall life satisfaction, ranging from 0 (lowest) to 5 (highest). The outcomes were all-cause and cause-specific mortality. We used multivariable Cox regression to estimate hazard ratios (HR) for the associations of interest. RESULTS: Among 165,842 eligible participants, 12,261 all-cause deaths were observed over a median of 12.9-year follow-up. Overall life satisfaction was inversely associated with all-cause mortality (adjusted HR 0.94 [95% CI: 0.93-0.95] per 1 score increment). Health satisfaction showed the strongest association with all-cause mortality, with a fully adjusted HR of 0.52 (95% CI: 0.49-0.55) for high/extreme satisfaction and 0.63 (95% CI: 0.59-0.66) for moderate satisfaction, compared with unsatisfaction (P-trend<0.001), independent of other satisfaction components, regardless of physical health and sociodemographics. The association for family, friendship, work and financial satisfaction was attenuated when adjusted for other life satisfaction components. Similar findings were observed for cause-specific mortality. LIMITATIONS: Observational study with single baseline measurement of life satisfaction precludes the ability to establish causal relationship. CONCLUSIONS: Higher overall life satisfaction was associated with lower mortality. As the major contributor to lower mortality regardless of physical health and sociodemographics, health satisfaction could be an important target of positive psychological interventions for longevity.


Assuntos
Doenças Cardiovasculares , Satisfação Pessoal , Humanos , Estudos de Coortes , Causas de Morte , Estudos Prospectivos , Fatores de Risco
9.
J Affect Disord ; 347: 57-65, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-37995923

RESUMO

BACKGROUND: Child maltreatment can increase the risk of lifetime non-suicidal self-injury (NSSI) and suicidal self-injury (SSI), but there is limited knowledge regarding the differences of potentially psychological mechanisms between NSSI with and without SSI. METHODS: Participants, 3918 community-based Chinese young men aged 18-34 years in Chengdu, were included in this study. We investigated the association between depression, anxiety, psychosis, child maltreatment, adulthood traumatic events, impulsivity, alcohol dependence, drug abuse, and lifetime of NSSI among participants with and without SSI. Parallel mediation analysis was utilized to explore the mediators for the relation between child maltreatment and NSSI. RESULTS: The prevalence of lifetime NSSI was 6.1 % (95 % CI: 5.4 %-6.9 %) among young men. Anxiety and impulsivity partially mediated the effect of child maltreatment on NSSI either with (indirect effect: 51.2 %) or without SSI (indirect effect: 34.3 %). Depression was independently and significantly associated with only NSSI but not with NSSI+SSI. Alcohol dependence and psychosis were independently and significantly associated with NSSI+SSI and mediated the effect of child maltreatment on NSSI+SSI. LIMITATIONS: The cross-sectional survey data limits the robustness of the proof to the causal relationships. CONCLUSIONS: Anxiety and impulsivity are associated with NSSI either with or without SSI and partially mediate the effect of child maltreatment on NSSI. Depression is associated with only NSSI, while alcohol dependence and psychosis are only associated with NSSI+SSI. It could be crucial to improve treatment and recovery of alcohol dependence and psychosis for preventing young men engaged in NSSI from attempting SSI.


Assuntos
Experiências Adversas da Infância , Alcoolismo , Comportamento Autodestrutivo , Adulto , Humanos , Masculino , Ansiedade/epidemiologia , Ansiedade/psicologia , Estudos Transversais , Comportamento Impulsivo , Fatores de Risco , Comportamento Autodestrutivo/epidemiologia , Comportamento Autodestrutivo/psicologia , Ideação Suicida , Adolescente , Adulto Jovem
10.
J Affect Disord ; 347: 500-508, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38065477

RESUMO

BACKGROUND: It is unclear about the mutual impact of COVID-19 related psychological stress and infection on mental health of adolescent and youth students. This study aimed to explore the mutual impact of COVID-19 related psychological stress and infection on mental health problems among students. METHODS: This study was conducted from December 14, 2022 to February 28, 2023 in Sichuan, China. Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, PTSD Checklist for DSM-5, Insomnia Severity Index, and Internet Addiction Test were used. Participants were grouped by COVID-19 infection and psychological stress level. The differences among groups were compared, and logistic regression analysis was used to investigate risk factors for depression, anxiety, PTSD and insomnia among groups. RESULTS: Of 90,118 participants, 82,873 (92.0 %) finished the questionnaires and were included in the study. Of 82,873 participants, 33,314 (40.2 %) reported to be infected with COVID-19. Participants had depression symptoms (38.1 %), anxiety symptoms (31.8 %), PTSD (33.9 %), insomnia (34.0 %), and internet addiction (60.3 %). Compared with participants uninfected with low psychological stress level, the risk for symptoms of depression, anxiety, PTSD and insomnia increased by 9.6 %, 12.3 %, 6.6 %, and 12.0 % in participants infected with low psychological stress level (p < 0.001), 106.8 %, 125.9 %, 125.2 %, and 95.7 % in participants uninfected with high psychological stress level (p < 0.001), and 147.3 %, 161.1 %, 158.7 %, and 141.0 % in participants infected with high psychological stress level (p < 0.001). LIMITATION: This study is a cross-sectional design, and no causal associations should be inferred. Infection status was based on self-report of participants with infectious symptoms. CONCLUSION: COVID-19 related psychological stress and infection per se have mutually overlapping impacts on mental health problems among students. Further health policies and psychosocial interventions should be developed to reduce mutually overlapping impact and improve the long-term mental health among students.


Assuntos
COVID-19 , Distúrbios do Início e da Manutenção do Sono , Adolescente , Humanos , COVID-19/epidemiologia , Saúde Mental , SARS-CoV-2 , Pandemias , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estudos Transversais , Ansiedade/diagnóstico , China/epidemiologia , Depressão/diagnóstico
11.
Small ; 20(6): e2304563, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37786270

RESUMO

It is substantially challenging for non-centrosymmetric (NCS) Hg-based chalcogenides for infrared nonlinear optical (IR-NLO) applications to realize wide band gap (Eg > 3.0 eV) and sufficient phase-matching (PM) second-harmonic-generation intensity (deff > 1.0 × benchmark AgGaS2 ) simultaneously due to the inherent incompatibility. To address this issue, this work presents a diagonal synergetic substitution strategy for creating two new NCS quaternary Hg-based chalcogenides, AEHgGeS4 (AE = Sr and Ba), based on the centrosymmetric (CS) AEIn2 S4 . The derived AEHgGeS4 displays excellent NLO properties such as a wide Eg (≈3.04-3.07 eV), large PM deff (≈2.2-3.0 × AgGaS2 ), ultra-high laser-induced damage threshold (≈14.8-15 × AgGaS2 ), and suitable Δn (≈0.19-0.24@2050 nm), making them highly promising candidates for IR-NLO applications. Importantly, such excellent second-order NLO properties are primarily attributed to the synergistic combination of tetrahedral [HgS4 ] and [GeS4 ] functional primitives, as supported by detailed theoretical calculations. This study reports the first two NCS Hg-based materials with well-balanced comprehensive properties (i.e., Eg > 3.0 eV and deff > 1.0 × benchmark AgGaS2 ) and puts forward a new design avenue for the construction of more efficient IR-NLO candidates.

12.
Int J Biol Macromol ; 258(Pt 2): 128965, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38151087

RESUMO

Tobacco mosaic virus (TMV) is the most widely spread and harmful virus in the world, causing serious economic losses annually. However, the low anti-erosion ability of the pesticides for TMV management make it easy to be washed by the rain, which makes the effective duration of the pesticides shorter. In this paper, a new bio-based nanogel with superior antiviral activity was reported, and its slow-release behavior, rain erosion resistance and the antiviral mechanism was systematically studied. The results determined that the nanogels (Zn2+@ALGNP and Zn2+@ALGNP@PL) exhibited sustained releasing of Zn2+ with a 7 days duration, and the ε-PL coating could enhance the releasing rate of Zn2+. Moreover, Zn2+@ALGNP@PL displayed a lower contact angle, indicating greater adhesion to the leaf surface, and in consequence imposed better resistance to simulate rain erosion than pure Zn2+. Strikingly, Zn2+@ALGNP@PL could inhibit plant virus infection by aggregating the virions and reducing its coat protein stability, as well as inducing the efficient expression of reactive oxygen species, antioxidant enzymes and resistance genes to enhance plant resistance and promote plant growth. Overall, this study had successfully developed a high rain-erosion resistant bio-based nanogel capable of continue to induce resistant plants and promote plant growth.


Assuntos
Praguicidas , Polietilenoglicóis , Polietilenoimina , Vírus do Mosaico do Tabaco , Nanogéis , Nicotiana , Doenças das Plantas , Antivirais/farmacologia , Praguicidas/farmacologia
13.
Front Psychiatry ; 14: 1243619, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37953935

RESUMO

Background: Internet addiction (IA) among students, worsened by Coronavirus disease 2019 (COVID-19) pandemic, has become a social problem with the digitalization of school learning and many aspects of daily life. However, few studies on IA have been conducted among students after the lifting of COVID-19 restrictions in China. Method: This large-sample, cross-sectional, online survey was conducted to explore the characteristics of IA and the association among IA, academic satisfaction, and mental health problems from December 14, 2022 to February 28, 2023 in Sichuan, China. All participants (N = 22,605) were students in colleges and universities, recruited via their teachers and professors. Results: Of all the participants, 14,921 (66.0%) participants had IA. Participants with IA were more likely to have depression symptom, anxiety symptom, insomnia, and lifetime suicidal ideation. In addition, participants with severe IA had significantly higher rates of mental health problems (e.g., depression, anxiety, insomnia, and suicidal ideation) than those with mild IA. A significant IA-by-academic satisfactory-interaction on mental health was identified: participants with higher level of IA showed particularly severe symptom of depression, anxiety and insomnia when affected by low satisfactory of academy (p < 0.001). Conclusion: This study reveals that IA has a significantly negative impact on mental health among college students after the lifting of COVID-19 restrictions in China. IA and academic satisfaction have interactive impacts on mental health problems among students. Further educational and health policies and psychosocial interventions should be developed to reduce IA and enhance academic satisfaction for improving students' mental health.

14.
Front Psychiatry ; 14: 1248541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645634

RESUMO

Background: Although the COVID-19 pandemic has greatly changed the way students studied, it is still unknown about the impact of the COVID-19 pandemic on students' academic performance and mental health. Objective: To explore the academic performance and mental health status of middle and high school students after the lifting of COVID-19 restrictions in China. Methods: An online survey was conducted in Sichuan province, China from Dec 14, 2022 to Feb 28, 2023. All participants were students in middle and high schools, recruited via their teachers. The general information, COVID-19-related information, and academic performance were collected. The Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Internet Addiction Test (IAT) were used to assess the mental health problems. Results: Of 60,268 participants, 36,247 (60.2%) middle and high school students reported that their studies were affected by the COVID-19 pandemic, and 24,864 (41.2%) reported that their academic performance had worsened. The prevalence of depression and anxiety symptoms was 38.4 and 32.7%, respectively. There was a significant association between academic performance change and mental health problems. The logistic regression analysis showed that improved academic performance was a protective factor for depression, and declined academic performance was a risk factor for depression and anxiety. Being COVID-19 infected, family members being infected, with quarantine experience, and with COVID-19-related stigma were risk factors for depression and anxiety. Conclusion: Academic studies and mental health status of middle and high school students in Sichuan, China have been negatively impacted by the COVID-19 pandemic, even after the lifting of COVID-19 restrictions. Students' academic performance, academic concerns, and mental health status should be considered for educational policymakers and institutions to improve students' academic studies and mental well-being.

15.
Plant Cell Environ ; 46(11): 3592-3610, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37551976

RESUMO

Control of plant virus diseases largely depends on the induced plant defence achieved by the external application of synthetic chemical inducers with the ability to modify defence-signalling pathways. However, most of the molecular mechanisms underlying these chemical inducers remain unknown. Here, we developed a chitosan-coated lentinan-loaded hydrogel and discovered how it protects plants from different virus infections. The hydrogel was synthesized by coating chitosan on the surface of the calcium alginate-lentinan (LNT) hydrogel (SL-gel) to form a CSL-gel. CSL-gels exhibit the capacity to prolong the stable release of lentinan and promote Ca2+ release. Application of CSL-gels on the root of plants induces broad-spectrum resistance against plant viruses (TMV, TRV, PVX and TuMV). RNA-seq analysis identified that Nicotiana benthamiana calmodulin-like protein gene 3 (NbCML3) is upregulated by the sustained release of Ca2+ from the CSL-gel, and silencing and overexpression of NbCML alter the susceptibility and resistance of tobacco to TMV. Our findings provide evidence that this novel and synthetic CSL-gel strongly inhibits the infection of plant viruses by the sustainable release of LNT and Ca2+ . This study uncovers a novel mode of action by which CSL-gels trigger NbCML3 expression through the stable and sustained release of Ca2+ .

16.
Front Psychiatry ; 14: 1170540, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484667

RESUMO

Objective: Infectious diseases including COVID-19 and mental disorders are two of the most common health conditions associated with stigma. However, the comparative stigma of these two conditions has received less attention in research. This study aimed to compare the prevalence of stigmatizing views toward people with COVID-19 and mental disorders and the factors associated with these views, among a large sample of adolescent and young adult students in China. Methods: A total of 9,749 adolescents and young adults aged 15-24 years completed a survey on stigmatizing attitudes toward COVID-19 and mental disorders, as well as mental health-related factors, including general mental health status and symptoms of depression, anxiety, insomnia, and post-traumatic stress disorder (PTSD). Multivariable linear regression analyses were conducted to identify factors associated with stigmatizing views. Findings: The prevalence of COVID-19 and mental disorders-related stigma was 17.2% and 40.7%, respectively. COVID-19-related stigma scores were significantly higher among male students (ß = 0.025, p < 0.05), those without quarantine experience (ß = 0.035, p < 0.001), those with lower educational level (p < 0.001), those with lower family income (p < 0.01), and those with higher PTSD symptoms (ß = 0.045, p < 0.05). Mental disorder-related stigma scores were significantly higher among individuals with average and lower-than-average levels of family income (p < 0.01), depression symptoms (ß = 0.056, p < 0.001), anxiety symptoms (ß = 0.051, p < 0.001), and mental health problems (ß = 0.027, p < 0.05). Conclusion: The stigma of mental disorders is higher in the youth population than the stigma of COVID-19. Factors associated with stigmatizing attitudes toward people with COVID-19 and mental disorders varied across the youth. Stigma-reduction interventions among the youth should be targeted specifically to COVID-19 or mental disorders conditions.

17.
Front Plant Sci ; 14: 1136884, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063233

RESUMO

Cold environmental conditions may often lead to the early flowering of plants, and the mechanism by cold-induced flowering remains poorly understood. Microscopy analysis in this study demonstrated that cold conditioning led to early flower bud differentiation in two tobacco strains and an Agilent Tobacco Gene Expression microarray was adapted for transcriptomic analysis on the stem tips of cold treated tobacco to gain insight into the molecular process underlying flowering in tobacco. The transcriptomic analysis showed that cold treatment of two flue-cured tobacco varieties (Xingyan 1 and YunYan 85) yielded 4176 and 5773 genes that were differentially expressed, respectively, with 2623 being commonly detected. Functional distribution revealed that the differentially expressed genes (DEGs) were mainly enriched in protein metabolism, RNA, stress, transport, and secondary metabolism. Genes involved in secondary metabolism, cell wall, and redox were nearly all up-regulated in response to the cold conditioning. Further analysis demonstrated that the central genes related to brassinosteroid biosynthetic pathway, circadian system, and flowering pathway were significantly enhanced in the cold treated tobacco. Phytochemical measurement and qRT-PCR revealed an increased accumulation of brassinolide and a decreased expression of the flowering locus c gene. Furthermore, we found that overexpression of NtBRI1 could induce early flowering in tobacco under normal condition. And low-temperature-induced early flowering in NtBRI1 overexpression plants were similar to that of normal condition. Consistently, low-temperature-induced early flowering is partially suppressed in NtBRI1 mutant. Together, the results suggest that cold could induce early flowering of tobacco by activating brassinosteroid signaling.

18.
Pestic Biochem Physiol ; 191: 105342, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36963924

RESUMO

Ribosome-inactivating proteins (RIPs) are toxic N-glycosylase that act on eukaryotic and prokaryotic rRNAs, resulting in arrest protein synthesis. RIPs are widely found in higher plant species and display strong antiviral activity. Previous studies have shown that PAP and α-MMC have antiviral activity against TMV. However, the localization of RIPs in plant cells and the mechanism by which RIPs activate plant defense against several plant viruses remain unclear. In this study, we obtained four RIPs (the C-terminal deletion mutant of pokeweed antiviral proteins (PAP-c), alpha-momorcharin (α-MMC), momordica anti-HIV protein of 30 kDa (MAP30) and luffin-α). The subcellular localization results indicated that these four RIPs were located on the plant cell membrane. Heterologous expression of RIPs (PAP-c, α-MMC, MAP30, luffin-α) enhanced tobacco mosaic virus (TMV) resistance in N. benthamiana. Compared with the control treatment, these RIPs significantly reduced the TMV content (149-357 fold) and altered the movement of TMV in the leaves of N. benthamiana. At the same time, heterologous expression of RIPs (MAP30 and luffin-α) could relieve TMV-induced oxidative damage, significantly inducing the expression of plant defense genes including PR1 and PR2. Furthermore, application of these RIPs could inhibit the infection of turnip mosaic virus (TuMV) and potato virus x (PVX). Therefore, this study demonstrated that MAP30 and luffin-α could be considered as new, effective RIPs for controlling plant viruses by activating plant systemic defense.


Assuntos
Momordica , Vírus de Plantas , Vírus do Mosaico do Tabaco , Momordica/metabolismo , HIV/metabolismo , Plantas , Vírus de Plantas/metabolismo , Antivirais/farmacologia , Ribossomos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
19.
Small ; 19(19): e2300248, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36775973

RESUMO

Inorganic chalcogenides have been studied as the most promising infrared (IR) nonlinear optical (NLO) candidates for the past decades. However, it is proven difficult to discover high-performance materials that combine the often-incompatible properties of large energy gap (Eg ) and strong second harmonic generation (SHG) response (deff ), especially for rare-earth chalcogenides. Herein, centrosymmetric Cs3 [Sb3 O6 ][Ge2 O7 ] is selected as a maternal structure and a new noncentrosymmetric rare-earth oxychalcogenide, namely, Nd3 [Ga3 O3 S3 ][Ge2 O7 ], is successfully designed and obtained by the module substitution strategy for the first time. Especially, Nd3 [Ga3 O3 S3 ][Ge2 O7 ] is the first case of breaking the trade-off relationship between wide Eg (>3.5 eV) and large deff (>0.5 × AgGaS2 ) in rare-earth chalcogenide system, and thus displays an outstanding IR-NLO comprehensive performance. Detailed structure analyses and theoretical studies reveal that the NLO effect originates mainly from the cooperation of heteroanionic [GaO2 S2 ] and [NdO2 S6 ] asymmetric building blocks. This work not only presents an excellent rare-earth IR-NLO candidate, but also plays a crucial role in the rational structure design of other NLO materials in which both large Eg and strong deff are pursued.

20.
J Food Sci ; 88(4): 1224-1236, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36815593

RESUMO

Husks are the main source of bran and furfural flavor in traditional Chinese light-aroma Baijiu, but they negatively affect its smell and taste. Here, bran husks were replaced with fresh bamboo to brew light-aroma Baijiu. Flavor components in Jiupei and Baijiu were detected through headspace solid-phase microextraction with gas chromatography-mass spectrometry, and physicochemical properties were assessed; flavor results were obtained from correlation, principal component, and cluster analyses. Starch and reducing sugar content in Jiupei negatively correlated with moisture, alcohol content, and acidity. Fresh bamboo reduced furfural from bran husks in Jiupei by 88.5% and increased alcohol distillation by 51%; it also improved starch efficiency (5%). Surprisingly, isovanillin was found to be present in Baijiu. Total Baijiu yield (57% ± 2.01%) was attained when crushed bamboo size was 1.5 cm × 0.3 cm × 0.3 cm. This study supports the use of fresh bamboo (an eco-friendly alternative for husks) in brewing light-aroma Baijiu. PRACTICAL APPLICATION: The use of fresh bamboo as a replacement for rice husks in brewing light-aroma Baijiu was investigated. It attenuated the chaff taste in light-aroma Baijiu and increased the liquor yield. Surprisingly, isovanillin was also present in the base Baijiu, and it added to the fragrance. This study not only supports the use of bamboo as an auxiliary material for brewing light-aroma Baijiu but also provides a reference for brewing light-aroma Baijiu with alternative auxiliary materials.


Assuntos
Odorantes , Oryza , Odorantes/análise , Furaldeído , Bebidas Alcoólicas/análise
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