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1.
Cell ; 186(17): 3577-3592.e18, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37499659

RESUMO

Hybrid sterility restricts the utilization of superior heterosis of indica-japonica inter-subspecific hybrids. In this study, we report the identification of RHS12, a major locus controlling male gamete sterility in indica-japonica hybrid rice. We show that RHS12 consists of two genes (iORF3/DUYAO and iORF4/JIEYAO) that confer preferential transmission of the RHS12-i type male gamete into the progeny, thereby forming a natural gene drive. DUYAO encodes a mitochondrion-targeted protein that interacts with OsCOX11 to trigger cytotoxicity and cell death, whereas JIEYAO encodes a protein that reroutes DUYAO to the autophagosome for degradation via direct physical interaction, thereby detoxifying DUYAO. Evolutionary trajectory analysis reveals that this system likely formed de novo in the AA genome Oryza clade and contributed to reproductive isolation (RI) between different lineages of rice. Our combined results provide mechanistic insights into the genetic basis of RI as well as insights for strategic designs of hybrid rice breeding.


Assuntos
Tecnologia de Impulso Genético , Oryza , Hibridização Genética , Oryza/genética , Melhoramento Vegetal/métodos , Isolamento Reprodutivo , Infertilidade das Plantas
2.
Environ Res ; 222: 115344, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36693460

RESUMO

BACKGROUND: Numerous studies have demonstrated that greenspace(GS) exposure is associated with health improvements in individuals with hypertension and diabetes. However, studies examining the associations between multiple GS exposures and chronic health conditions in developing countries are limited. METHODS: Geospatial data and spatial analysis were employed to objectively measure the total neighbourhood vegetative cover (mean value of normalised difference vegetation index [NDVI] within specific buffer zone) and proximity to park-based GS (network distance from home to the entrance of park-based GS). Street view imagery and machine learning techniques were used to measure the subjective perceptions of street GS quality. A multiple linear regression model was applied to examine the associations between multiple GS exposures and the prevalence of hypertension and diabetes in neighbourhoods located in Qingdao, China. RESULTS: The model explained 29.8% and 28.2% of the prevalence of hypertension and diabetes, respectively. The results suggested that: 1) the total vegetative cover of the neighbourhood was inversely correlated with the prevalence of hypertension (ß = -0.272, p = 0.013, 95% confidence interval (CI): [-1.332, -0.162]) and diabetes (ß = -0.230, p = 0.037, 95% CI: [-0.720, -0.008]). 2) The street GS quality was negatively correlated with the prevalence of hypertension (ß = -0.303, p = 0.007, 95% CI: [-2.981, -0.491]) and diabetes (ß = -0.309, p = 0.006, 95% CI: [-1.839, -0.314]). 3) Proximity to park-based GS and the prevalence of hypertension and diabetes mellitus were not significantly correlated. CONCLUSIONS: This study used subjective and objective methods to comprehensively assess the greenspace exposure from overhead to eye level, from quantity, proximity to quality. The results demonstrated the beneficial relationships between street GS quality, total vegetative cover, and chronic health in a rapidly urbanising Chinese city. Furthermore. the effect of street GS quality was more pronounced in potentially mitigating chronic health problems, and improving the quality of street GS might be an efficient and effective intervention pathway for addressing chronic health issues in densely populated cities.


Assuntos
Diabetes Mellitus , Parques Recreativos , Humanos , Cidades , População Urbana , China
3.
J Pediatr ; 240: 177-185, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543620

RESUMO

OBJECTIVE: To systematically describe the short stature of patients with Diamond-Blackfan anemia and to explore factors affecting the height development of patients with Diamond-Blackfan anemia. STUDY DESIGN: This cross-sectional study was conducted at the Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, and the height, weight, and clinical data of 129 patients with Diamond-Blackfan anemia were collected from June 2020 to September 2020. RESULTS: The median height-age-z score (HAZ) of children affected by Diamond-Blackfan anemia was -1.54 (-6.36-1.96). Short stature was found in 37.98% of the patients. Specific Diamond-Blackfan anemia growth curves were developed for weight, height, and body mass index, separately for male and female patients. Multivariable logistic regression models showed that female sex (aOR 4.92; 95% CI 1.29-18.71; P = .0195), underweight (aOR 10.41, 95% CI 1.41-76.98, P = .0217), cardiovascular malformations (aOR 216.65; 95% CI 3.29-14279.79; P = .0118), and RPL11(aOR 29.14; 95% CI 1.18-719.10; P = .0392) or RPS26 (aOR 53.49; 95% CI 1.40-2044.30; P = .0323) mutations were independent risk factors for short stature. In the subgroup of patients who were steroid-dependent, patients with a duration of steroid therapy over 2 years (OR 2.95; 95% CI 1.00-8.66; P = .0494) or maintenance dose of prednisone >0.1 mg/kg per day (OR 3.30; 95% CI 1.02-10.72; P = .0470) had a higher incidence of short stature. CONCLUSIONS: Patients with Diamond-Blackfan anemia had a high prevalence of short stature. The risk of short stature increased with age and was associated with sex, underweight, congenital malformations, and RPL11 or RPS26 mutations. The duration of steroid therapy and maintenance dose of steroid was significantly associated with the incidence of short stature in steroid-dependent patients with Diamond-Blackfan anemia.


Assuntos
Anemia de Diamond-Blackfan/epidemiologia , Nanismo/epidemiologia , Anormalidades Múltiplas/epidemiologia , Adolescente , Fatores Etários , Anemia de Diamond-Blackfan/tratamento farmacológico , Anemia de Diamond-Blackfan/genética , Criança , Pré-Escolar , China , Estudos Transversais , Nanismo/etiologia , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Humanos , Lactente , Masculino , Mutação , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Proteínas Ribossômicas , Fatores Sexuais
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(10): 1143-1148, 2022 Oct 15.
Artigo em Zh | MEDLINE | ID: mdl-36305116

RESUMO

OBJECTIVES: To investigate the distribution of body mass index (BMI) and risk factors for obesity in children with Diamond-Blackfan Anemia (DBA). METHODS: The children with DBA who attended National Clinical Research Center for Blood Diseases, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, from January 2003 to December 2020 were enrolled as subjects. The related clinical data and treatment regimens were recorded. The height and weight data measured within 1 week before or after follow-up time points were collected to calculate BMI. The risk factors for obesity were determined by multivariate regression analysis in children with DBA. RESULTS: A total of 129 children with DBA were enrolled, among whom there were 80 boys (62.0%) and 49 girls (38.0%), with a median age of 49 months (range 3-189 months). The prevalence rate of obesity was 14.7% (19/129). The multivariate logistic regression analysis showed that the absence of ribosomal protein gene mutation was closely associated with obesity in children with DBA (adjusted OR=3.63, 95%CI: 1.16-11.38, adjusted P=0.027). In children with glucocorticoid-dependent DBA, obesity was not associated with age of initiation of glucocorticoid therapy, duration of glucocorticoid therapy, and maintenance dose of glucocorticoids (P>0.05). CONCLUSIONS: There is a high prevalence rate of obesity in children with DBA, and the absence of ribosomal protein gene mutation is closely associated with obesity in children with DBA.


Assuntos
Anemia de Diamond-Blackfan , Obesidade Infantil , Criança , Masculino , Feminino , Humanos , Anemia de Diamond-Blackfan/epidemiologia , Anemia de Diamond-Blackfan/genética , Obesidade Infantil/complicações , Glucocorticoides/uso terapêutico , Prevalência , Fatores de Risco , Proteínas Ribossômicas/genética , Mutação
5.
Opt Lett ; 45(8): 2255-2258, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32287207

RESUMO

We report on a compact mid-infrared laser architecture, comprising a chain of $ {\rm ZnGeP}_2 $ZnGeP2-based optical parametric amplifiers (OPAs), which afford a higher energy yield ($ \mathbin{\lower.3ex\hbox{$\buildrel \lt \over{\smash{\scriptstyle\sim}\vphantom{_x}}$}} 60\;\unicode{x00B5} {\rm J} $∼x<60µJ at 1 kHz) compared to most conventional OPA gain media transparent in the 2-8-µm wavelength range. Specifically, our OPA scheme allows ready tunability in the molecular fingerprint regime and is tailored for strong-field excitation and coherent control of both stretch and bend (or torsional) vibrational modes in molecules. The OPAs are pumped and directly seeded (via supercontinuum generation) by a 2-µm, 3-ps Ho:YLF regenerative amplifier. The compressibility of the OPA output is demonstrated by a representative measurement of the near-Gaussian temporal profile of a dispersion-compensated 105-fs idler pulse at a central wavelength of 5.1 µm, corresponding to ${\sim}6 $∼6 optical cycles. Detailed numerical simulations closely corroborate the experimental measurements, providing a benchmark and a platform to further explore the parameter space for future design, optimization, and implementation of high-energy, ultrafast, mid-infrared laser schemes.

7.
Opt Lett ; 43(18): 4329-4332, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30211856

RESUMO

High-energy, multi-octave supercontinuum (SC) generation in bulk media pumped with picosecond pulses in the mid-infrared, though pivotal in a myriad of applications, poses severe constraints due to wavelength scaling of the critical power criterion and the propensity to induce avalanche-ionization-seeded breakdown mechanisms. Here, we demonstrate a simple experimental geometry, relying on a very low numerical aperture for the pump pulse, and a crystal length commensurate with the Rayleigh length of the focusing geometry, generating a multi-octave, stable SC in yttrium aluminum garnet (YAG). The SC ranges from 500 nm to 3.5 µm (measured at -30 dB with spectral components at wavelengths up to 4.5 µm) when pumped by a 3 ps pulse centered at 2.05 µm in the anomalous dispersion regime. We also investigate the dynamics of filament formation in this interaction regime by monitoring the spectral and temporal evolution of the pulse during its propagation through the length of the crystal.

8.
Int J Med Sci ; 15(7): 738-747, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910679

RESUMO

Basal-like breast cancer (BLBC) is resistant to endocrinotherapy and targeted therapy and new molecular therapies are needed for BLBC. In this study, we evaluated the role of DUSP1 and DUSP5, negative regulators of mitogen-activated protein kinase pathway, in the aggressiveness of BLBC. MDA-MB-231 cells were given paclitaxel (PTX) treatment and subsequently PTX resistant cell clones were established. Microarray analysis, real-time quantitative reverse transcription PCR (qRT-PCR), and online analysis of large cohorts of breast cancer patients were performed. The PTX resistant cells showed stronger cell proliferation ability by exhibiting the upregulation of CENPF, CDC6, MCM3, CLSPN and SMC1A expression. Furthermore, DUSP1 and DUSP5 expression was significantly downregulated in PTX resistant cells. In addition, in large breast cancer patients' database, both DUSP1 and DUSP5 correlated negatively with higher histological grade. DUSP1 low expression was obvious in HER2 positive and basal like while DUSP5 low expression was peculiar for basal like compared with other subtypes. Remarkably, low expression of DUSP5, but not DUSP1, was significantly correlated with poor survival of BLBC patients. In conclusion, our data suggest that loss of DUSP5 expression results in PTX resistance and tumor progression, providing a rationale for a therapeutic agent that restores DUSP5 in BLBC.


Assuntos
Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fosfatases de Especificidade Dupla/metabolismo , Paclitaxel/farmacologia , Antineoplásicos Fitogênicos , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células , Humanos , Prognóstico , Regulação para Cima
10.
Org Biomol Chem ; 14(33): 7875-82, 2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27454320

RESUMO

Lengthy peptides corresponding to the C-terminal heptad repeat (C-peptides) of human immunodeficiency virus type 1 (HIV-1) gp41 are potent inhibitors against virus-cell fusion. Designing short C-peptide-based HIV-1 fusion inhibitors could potentially redress the physicochemical and technical liabilities of a long-peptide therapeutic. However, designing such inhibitors with high potency has been challenging. We generated a conjugated architecture by incorporating small-molecule inhibitors of gp41 into the N-terminus of a panel of truncated C-peptides. Among these small molecule-capped short peptides, the 26-residue peptide Indole-T26 inhibited HIV-1 Env-mediated cell-cell fusion and viral replication at low nanomolar levels, reaching the potency of the only clinically used 36-residue peptide T20 (enfuvirtide). Collectively, our work opens up a new avenue for developing short peptide-based HIV-1 fusion inhibitors, and may have broad applicability to the development of modulators of other class I fusion proteins.


Assuntos
Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , Inibidores da Fusão de HIV/farmacologia , HIV-1/efeitos dos fármacos , Peptídeos/farmacologia , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Linhagem Celular , Proteína gp41 do Envelope de HIV/química , Inibidores da Fusão de HIV/síntese química , Inibidores da Fusão de HIV/química , Humanos , Estrutura Molecular , Peptídeos/síntese química , Peptídeos/química , Replicação Viral/efeitos dos fármacos
11.
Appl Opt ; 55(12): 3294-6, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27140101

RESUMO

Our experiment is expected to provide an approach for realizing ultranarrow linewidth for a spectral beam combined diode laser bar. The beams of a diode laser bar are combined in a fast axis after a beam transformation system. With the help of relay optics and a transform lens with a long focal length of 1.5 m, the whole wavelength of a spectral combined laser bar can be narrowed down to 0.48 nm from more than 10 nm. We have achieved 56.7 W cw from a 19-element single bar with an M2 of 1.4 (in horizontal direction)×11.6 (in vertical direction). These parameters are good evidence that all the beams from the diode laser bar are combined together to increase the brightness.

12.
Oncol Lett ; 28(2): 363, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38903699

RESUMO

Primary mantle cell lymphoma (MCL) in the gastrointestinal tract is rare, accounting for 4-9% of all reported cases of gastrointestinal non-Hodgkin lymphoma. Furthermore, involvement of the entire gastrointestinal tract in MCL is rare. The present report describes an example of MCL characterized by numerous diffuse polypoid lesions along the whole digestive tract. In particular, there was a focus on the endoscopic presentation of the digestive tract. The patient initially received a treatment regimen of rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone. After two cycles of treatment, the regimen was changed to rituximab combined with etoposide, oxaliplatin and ifosfamide, with the addition of ibrutinib capsules. Patients with MCL have a poor prognosis; however, complete response can be achieved after treatment.

13.
Acta Psychol (Amst) ; 243: 104133, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280348

RESUMO

INTRODUCTION: Self-disclosure is integral to forming intimate connections within interpersonal exchanges. While its advantages are widely acknowledged, the cerebral basis of self-disclosure is not thoroughly understood. Insight into its neural underpinnings is crucial for refining therapeutic approaches, especially for challenges associated with self-disclosure. METHODS: Our study probed the association between spontaneous neural activity, gauged via resting-state fMRI, and self-disclosure tendencies among 258 healthy university students, employing Regional Homogeneity (ReHo) and behavioral correlation analysis. We also explored the mediating effect of self-consciousness on this relationship. RESULTS: The ReHo-behavior correlation analysis uncovered that higher ReHo values in the insula are predictive of greater self-disclosure in social settings. Additionally, the mediation analysis identified self-consciousness as a partial intermediary between spontaneous neural activity in the insula and self-disclosure behaviors. CONCLUSION: The findings imply that decreased similarity in the insula during rest-state may amplify self-conscious emotions such as embarrassment, thus illuminating the cognitive processes that underlie disclosure behaviors. Critically, these insights have practical ramifications for enhancing therapeutic methods and communication skills by aiding individuals in navigating self-consciousness obstacles, thereby promoting more transparent and efficacious self-disclosure.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Estado de Consciência , Emoções , Descanso , Mapeamento Encefálico
14.
Front Genet ; 15: 1441189, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39323867

RESUMO

Background: High heterogeneity is an essential feature of malignant tumors. This study aims to reveal the drivers of hepatocellular carcinoma heterogeneity for prognostic stratification and to guide individualized treatment. Methods: Omics data and clinical data for two HCC cohorts were derived from the Cancer Genome Atlas (TCGA) and the International Cancer Genome Atlas (ICGC), respectively. CNV data and methylation data were downloaded from the GSCA database. GSVA was used to estimate the transcriptional activity of KEGG pathways, and consensus clustering was used to categorize the HCC samples. The pRRophetic package was used to predict the sensitivity of samples to anticancer drugs. TIMER, MCPcounter, quanTIseq, and TIDE algorithms were used to assess the components of TME. LASSO and COX analyses were used to establish a prognostic gene signature. The biological role played by genes in HCC cells was confirmed by in vitro experiments. Results: We classified HCC tissues into two categories based on the activity of prognostic pathways. Among them, the transcriptional profile of cluster A HCC is similar to that of normal tissue, dominated by cancer-suppressive metabolic pathways, and has a better prognosis. In contrast, cluster B HCC is dominated by high proliferative activity and has significant genetic heterogeneity. Meanwhile, cluster B HCC is often poorly differentiated, has a high rate of serum AFP positivity, is prone to microvascular invasion, and has shorter overall survival. In addition, we found that mutations, copy number variations, and aberrant methylation were also crucial drivers of the differences in heterogeneity between the two HCC subtypes. Meanwhile, the TME of the two HCC subtypes is also significantly different, which offers the possibility of precision immunotherapy for HCC patients. Finally, based on the prognostic value of molecular subtypes, we developed a gene signature that could accurately predict patients' OS. The riskscore quantified by the signature could evaluate the heterogeneity of HCC and guide clinical treatment. Finally, we confirmed through in vitro experiments that RFPL4B could promote the progression of Huh7 cells. Conclusion: The molecular subtypes we identified effectively exposed the heterogeneity of HCC, which is important for discovering new effective therapeutic targets.

15.
Clin Interv Aging ; 19: 163-173, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38332967

RESUMO

Background: There is growing evidence that an antioxidant diet is a protective factor against frailty. However, few studies have examined the effect of comprehensive dietary antioxidants on frailty symptoms. The aim of this study was to examine the relationships between the composite dietary antioxidant index (CDAI) and frailty and the underlying mechanisms involved. Methods: Based on the National Health and Nutrition Survey (NHANES) 2003-2018, this study included 11,277 older persons aged ≥60 years. In this study, frailty was defined as having a total score >0.21 on the 49-item frailty index. Six dietary antioxidants were selected for use in calculating the CDAI. A weighted multiple logistic regression model with subgroup analysis and restricted cubic splines (RCSs) were used to examine the association between the CDAI and frailty. To examine the role of oxidative stress, mediation analyses were also conducted. Results: The association between the CDAI score and frailty risk was significant according to the multivariate model. Compared with participants in tertile 1, participants in both tertile 2 and tertile 3 had lower odds of developing frailty symptoms (OR=0.86; 95% CI=0.75-0.97; P=0.02; and OR=0.81; 95% CI=0.70-0.93; P=0.003). According to the subgroup analyses, the differences in interactions were not statistically significant. There was also a potential nonlinear relationship between the CDAI score and frailty risk. The serum albumin concentration and uric acid concentration had significant mediating effects on the association between the CDAI score and frailty index, with 19.25% (P=0.002) and 21.26% (P < 0.001) of the total, respectively. Conclusion: Frailty is negatively associated with the CDAI score, which may be partially mediated by oxidative stress.


Assuntos
Antioxidantes , Fragilidade , Idoso , Humanos , Idoso de 80 Anos ou mais , Idoso Fragilizado , Inquéritos Nutricionais , Dieta , Estresse Oxidativo
16.
Foods ; 13(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38928746

RESUMO

This study investigated the impact of different preheat treatments on the emulsifying and gel textural properties of soy protein with varying 11S/7S ratios. A mixture of 7S and 11S globulins, obtained from defatted soybean meal, was prepared at different ratios. The mixed proteins were subjected to preheating (75 °C, 85 °C, and 95 °C for 5 min) or non-preheating, followed by spray drying or non-spray drying. The solubility of protein mixtures rich in the 7S fraction tended to decrease significantly after heating at 85 °C, while protein mixtures rich in the 11S fraction showed a significant decrease after heating at 95 °C. Surprisingly, the emulsion stability index (ESI) of protein mixtures rich in the 7S fraction significantly improved twofold during processing at 75 °C. This study revealed a negative correlation between the emulsifying ability of soy protein and the 11S/7S ratio. For protein mixtures rich in either the 7S or the 11S fractions, gelling proprieties as well as emulsion activity index (EAI) and ESI showed no significant changes after spray drying; however, surface hydrophobicity was significantly enhanced following heating at 85 °C post-spray drying treatment. These findings provide insights into the alterations in gelling and emulsifying properties during various heating processes, offering great potential for producing soy protein ingredients with enhanced emulsifying ability and gelling property. They also contribute to establishing a theoretical basis for the standardized production of soy protein isolate with specific functional characteristics.

17.
Mol Plant ; 17(6): 900-919, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38704640

RESUMO

Although both protein arginine methylation (PRMT) and jasmonate (JA) signaling are crucial for regulating plant development, the relationship between these processes in the control of spikelet development remains unclear. In this study, we used the CRISPR/Cas9 technology to generate two OsPRMT6a loss-of-function mutants that exhibit various abnormal spikelet structures. Interestingly, we found that OsPRMT6a can methylate arginine residues in JA signal repressors OsJAZ1 and OsJAZ7. We showed that arginine methylation of OsJAZ1 enhances the binding affinity of OsJAZ1 with the JA receptors OsCOI1a and OsCOI1b in the presence of JAs, thereby promoting the ubiquitination of OsJAZ1 by the SCFOsCOI1a/OsCOI1b complex and degradation via the 26S proteasome. This process ultimately releases OsMYC2, a core transcriptional regulator in the JA signaling pathway, to activate or repress JA-responsive genes, thereby maintaining normal plant (spikelet) development. However, in the osprmt6a-1 mutant, reduced arginine methylation of OsJAZ1 impaires the interaction between OsJAZ1 and OsCOI1a/OsCOI1b in the presence of JAs. As a result, OsJAZ1 proteins become more stable, repressing JA responses, thus causing the formation of abnormal spikelet structures. Moreover, we discovered that JA signaling reduces the OsPRMT6a mRNA level in an OsMYC2-dependent manner, thereby establishing a negative feedback loop to balance JA signaling. We further found that OsPRMT6a-mediated arginine methylation of OsJAZ1 likely serves as a switch to tune JA signaling to maintain normal spikelet development under harsh environmental conditions such as high temperatures. Collectively, our study establishes a direct molecular link between arginine methylation and JA signaling in rice.


Assuntos
Arginina , Ciclopentanos , Oryza , Oxilipinas , Proteínas de Plantas , Proteína-Arginina N-Metiltransferases , Transdução de Sinais , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/genética , Oryza/metabolismo , Arginina/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Metilação , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Regulação da Expressão Gênica de Plantas
18.
Nat Commun ; 15(1): 4512, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802369

RESUMO

In higher plants, mature male gametophytes have distinct apertures. After pollination, pollen grains germinate, and a pollen tube grows from the aperture to deliver sperm cells to the embryo sac, completing fertilization. In rice, the pollen aperture has a single-pore structure with a collar-like annulus and a plug-like operculum. A crucial step in aperture development is the formation of aperture plasma membrane protrusion (APMP) at the distal polar region of the microspore during the late tetrad stage. Previous studies identified OsINP1 and OsDAF1 as essential regulators of APMP and pollen aperture formation in rice, but their precise molecular mechanisms remain unclear. We demonstrate that the Poaceae-specific OsSRF8 gene, encoding a STRUBBELIG-receptor family 8 protein, is essential for pollen aperture formation in Oryza sativa. Mutants lacking functional OsSRF8 exhibit defects in APMP and pollen aperture formation, like loss-of-function OsINP1 mutants. OsSRF8 is specifically expressed during early anther development and initially diffusely distributed in the microsporocytes. At the tetrad stage, OsSRF8 is recruited by OsINP1 to the pre-aperture region through direct protein-protein interaction, promoting APMP formation. The OsSRF8-OsINP1 complex then recruits OsDAF1 to the APMP site to co-regulate annulus formation. Our findings provide insights into the mechanisms controlling pollen aperture formation in cereal species.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Pólen , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Pólen/metabolismo , Pólen/genética , Pólen/crescimento & desenvolvimento , Mutação , Polinização , Membrana Celular/metabolismo , Plantas Geneticamente Modificadas , Tubo Polínico/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/genética
19.
Environ Sci Pollut Res Int ; 30(8): 20980-20994, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36264472

RESUMO

Faced with the requirement of carbon emission reduction in power industry, low-carbon power dispatch involving various low-carbon approaches has been recognized as one of effective ways. Concentrate on several important approaches: wind power integration and carbon reduction cooperation, it is necessary to deal with the uncertainties of wind power and carbon reduction modes for thermal power encountered in low-carbon power dispatch. For this purpose, this paper firstly presents a distributed robust optimization model synthetically considering robustness, economy, and environment. Next, wind power characterizations, scenario division and compression methods, and allocation algorithms of initial carbon emission rights are fully discussed for the convenience of model solution. Finally, empirical analysis shows that (1) the proposed model proves to be effective not only in coping with wind power uncertainties and reducing operating costs, (2) but also in dealing with the uncertainties of carbon reduction modes and reducing carbon emissions, and (3) low-carbon power dispatching strategies combining robustness, economy, and environment could be achieved through the proposed model and method, which are especially helpful to minimize interference from these two types of uncertainty more scientifically and reasonably.


Assuntos
Carbono , Vento , Incerteza , Algoritmos
20.
Nanoscale ; 15(10): 4801-4808, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36779310

RESUMO

Memristors with controllable resistive switching (RS) behavior have been considered as promising candidates for synaptic devices in next-generation neuromorphic computing. In this work, two-terminal memristors with controllable digital and analog RS behavior are fabricated based on two-dimensional (2D) WSe2 nanosheets. Under a relatively high operating voltage of 4 V, the memristor demonstrates stable and reliable non-volatile bipolar digital RS with a high switching ratio of 6.3 × 104. On the other hand, under a relatively low operation voltage, the memristor exhibits analog RS with a series of tunable resistance states. The fabricated memristors can work as an artificial synapse with fundamental synaptic functions, such as long-term potentiation (LTP) and depression (LTD) as well as paired-pulse facilitation (PPF). More importantly, the memristor demonstrates high conductance modulation linearity with the calculated nonlinear parameter for conductance as -0.82 in the LTP process, which is beneficial to improving the accuracy of neuromorphic computing. Furthermore, the neuromorphic computing of file types and image recognition can be emulated based on a constructed three-layer artificial neural network (ANN) with a recognition accuracy that can reach up to 95.9% for small digits. In addition, memristors can be used to emulate the learning-forgetting experience of the human brain. Consequently, the memristor based on 2D WSe2 nanosheets not only exhibits controllable RS behavior but also simulates synaptic functions and is expected to be a potential candidate for future neuromorphic computing applications.

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