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2.
Adv Mater ; : e2407822, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39104291

RESUMO

Spin-crossover (SCO) ferroelectrics with dual-function switches have attracted great attention for significant magnetoelectric application prospects. However, the multiferroic crystals with SCO features have rarely been reported. Herein, a molecular multiferroic Fe(II) crystalline complex [FeII(C8-F-pbh)2] (1-F, C8-F-pbh = (1Z,N'E)-3-F-4-(octyloxy)-N'-(pyridin-2-ylmethylene)-benzo-hydrazonate) showing the coexistence of ferroelectricity, ferroelasticity, and SCO behavior is presented for the first time. By H/F substitution, the low phase transition temperature (270 K) of the non-fluorinated parent compound is significantly increased to 318 K in 1-F, which exhibits a spatial symmetry breaking 222F2 type ferroelectric phase transition with clear room-temperature ferroelectricity. Besides, 1-F also displays a spin transition between high- and low-spin states, accompanied by the d-orbital breaking within the t2g 4eg 2 and t2g 6eg° configuration change of octahedrally coordinated FeII center. Moreover, the 222F2 type ferroelectric phase transition is also a ferroelastic one, verified by the ferroelectric domains reversal and the evolution of ferroelastic domains. To the knowledge, 1-F is the first multiferroic SCO molecular crystal. This unprecedented finding sheds light on the exploration of molecular multistability materials for future smart devices.

3.
Oral Oncol ; 157: 106963, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39032343

RESUMO

OBJECTIVE: There is a lack of effective biomarkers for predicting the distant metastasis in nasopharyngeal carcinoma (NPC). We aimed to explore the expression of FAP+Cancer-associated fibroblasts (CAFs) derived CXCL1 in NPC and its predictive values for distant metastasis and correlation with PD-L1 expression. MATERIALS AND METHODS: A total of 345 patients with locoregionally advanced NPC were retrospectively enrolled (the training cohort: the validation cohort = 160:185). Co-expression of CXCL1 and FAP and the expression of PD-L1 were detected by multi-immunofluorescence staining and immunohistochemistry, respectively. The primary end-point was distant metastasis-free survival (DMFS). The Kaplan-Meier method was used to calculate the survival. The Cox proportional hazards model was used to assess prognostic risk factors. RESULTS: A novel CXCL1+_FAP+ phenotype in CAFs was identified in NPC and then used to divide patients into low and high risk groups. Both in the training cohort and validation cohort, patients in the high risk group had poorer DMFS, overall survival (OS), progression-free survival (PFS) and locoregional relapse-free survival (LRFS) than patients in the low risk group. Multivariate analysis revealed CXCL1+_FAP+ phenotype was an independent prognostic factor for DMFS, OS, PFS and LRFS. Further results showed patients in the high risk group had higher PD-L1 expression than those in the low risk group. CONCLUSION: Our study showed CXCL1+_FAP+ phenotype in CAFs could effectively classified locoregionally advanced NPC patients into different risk groups for distant metastasis and might be a potential biomarker for anti-PD-1/PD-L1 immunotherapy.


Assuntos
Antígeno B7-H1 , Fibroblastos Associados a Câncer , Quimiocina CXCL1 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Antígeno B7-H1/metabolismo , Masculino , Feminino , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/mortalidade , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/mortalidade , Quimiocina CXCL1/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Adulto , Estudos Retrospectivos , Metástase Neoplásica , Prognóstico , Fenótipo , Biomarcadores Tumorais/metabolismo , Idoso , Serina Endopeptidases/metabolismo , Endopeptidases/metabolismo , Proteínas de Membrana/metabolismo
5.
Org Lett ; 26(27): 5833-5838, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38934368

RESUMO

Reported herein is a practical, economical, and efficient construction of 3-alkylated quinoxalin-2(1H)-ones with alkyl carboxylic acids and alkyl iodides by quinoxalin-2(1H)-one excitation and cobaloxime catalysis. Primary, secondary, and tertiary alkyl iodides and carboxylic acids all could be efficiently transferred into target products with excellent functional group tolerance. Mechanism studies reveal that the quinoxalin-2(1H)-one derivatives could be directly excited and yield alkyl carbon radicals from alkyl carboxylic acids and alkyl iodides with the aid of the cobaloxime complex.

6.
Front Med (Lausanne) ; 11: 1373062, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873193

RESUMO

Introduction: Cytomegalovirus (CMV) can cause various end-organ diseases in immunocompromised hosts, including allogeneic hematopoietic cell transplant (allo-HSCT) recipients. Interestingly, CMV viremia has been associated with various complications and poor prognosis in allo-HSCT recipients. Complications involving the central nervous system (CNS) occur in 9-14% of patients following allo-HSCT. However, autoimmune encephalitis (AE) secondary to CMV infection after allo-HSCT has rarely been reported. Here we report a case of possible AE following CMV viremia after allo-HSCT, which was successfully treated with high-dose pulsed methylprednisolone and intravenous immunoglobulins (IVIg). Case description: A 53-year-old female underwent allo-HSCT for T-lymphoblastic lymphoma/leukemia. The patient developed CMV viremia on day 36 after transplantation, and serum CMV-DNA remained positive after initiating ganciclovir antiviral therapy, turning negative one month later. Four months later, she started experiencing memory impairment, weakness in the left limbs, cognitive dysfunction, and hallucinations. A magnetic resonance imaging brain scan showed scattered ischemic lesions under the bilateral frontal cortex. Viral detection in cerebral spinal fluid (CSF) by next-generation gene sequencing technology showed no obvious abnormality. Antibodies specific to AE and paraneoplastic diseases in serum and CSF were absent. The oligoclonal bands in the CSF were detected using isoelectric focusing and immunofixation, and the results were negative. However, after extensive investigation regarding infections, autoimmune disorders, and recurrence of the malignancy, possible AE could not be excluded. The patient was treated with high-dose steroids combined with IVIg therapy; the patient's symptoms were significantly improved. Conclusion: The mechanisms of AE after allo-HSCT and the relationship with CMV infection should be further studied. Therefore, reporting this and similar cases will improve our awareness and understanding of the underlying disease mechanisms.

7.
Cell Rep Med ; 5(6): 101580, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38776913

RESUMO

Natural killer (NK) cell-based immunotherapy holds promise for cancer treatment; however, its efficacy remains limited, necessitating the development of alternative strategies. Here, we report that venetoclax, an FDA-approved BCL-2 inhibitor, directly activates NK cells, enhancing their cytotoxicity against acute myeloid leukemia (AML) both in vitro and in vivo, likely independent of BCL-2 inhibition. Through comprehensive approaches, including bulk and single-cell RNA sequencing, avidity measurement, and functional assays, we demonstrate that venetoclax increases the avidity of NK cells to AML cells and promotes lytic granule polarization during immunological synapse (IS) formation. Notably, we identify a distinct CD161lowCD218b+ NK cell subpopulation that exhibits remarkable sensitivity to venetoclax treatment. Furthermore, venetoclax promotes mitochondrial respiration and ATP synthesis via the NF-κB pathway, thereby facilitating IS formation in NK cells. Collectively, our findings establish venetoclax as a multifaceted immunometabolic modulator of NK cell function and provide a promising strategy for augmenting NK cell-based cancer immunotherapy.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Imunoterapia Adotiva , Células Matadoras Naturais , Leucemia Mieloide Aguda , Sulfonamidas , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Humanos , Sulfonamidas/farmacologia , Animais , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Camundongos , Imunoterapia Adotiva/métodos , Linhagem Celular Tumoral , NF-kappa B/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Camundongos Endogâmicos NOD
8.
Small ; : e2400415, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698600

RESUMO

Highly flexible and superelastic aerogels at large deformation have become urgent mechanical demands in practical uses, but both properties are usually exclusive. Here a trans-scale porosity design is proposed in graphene nanofibrous aerogels (GNFAs) to break the trade-off between high flexibility and superelasticity. The resulting GNFAs can completely recover after 1000 fatigue cycles at 60% folding strain, and notably maintain excellent structural integrity after 10000 cycles at 90% compressive strain, outperforming most of the reported aerogels. The mechanical robustness is demonstrated to be derived from the trans-scale porous structure, which is composed of hyperbolic micropores and porous nanofibers to enable the large elastic deformation capability. It is further revealed that flexible and superelastic GNFAs exhibit high sensitivity and ultrastability as an electrical sensors to detect tension and flexion deformation. As proof, The GNFA sensor is implemented onto a human finger and achieves the intelligent recognition of sign language with high accuracy by multi-layer artificial neural network. This study proposes a highly flexible and elastic graphene aerogel for wearable human-machine interfaces in sensor technology.

9.
Nat Commun ; 15(1): 4300, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773134

RESUMO

The chromatin modifier GRAIN WEIGHT 6a (GW6a) enhances rice grain size and yield. However, little is known about its gene network determining grain size. Here, we report that MITOGEN-ACTIVED PROTEIN KINASE 6 (OsMAPK6) and E3 ligase CHANG LI GENG 1 (CLG1) interact with and target GW6a for phosphorylation and ubiquitylation, respectively. Unexpectedly, however, in vitro and in vivo assays reveal that both of the two post-translational modifications stabilize GW6a. Furthermore, we uncover two major GW6a phosphorylation sites (serine142 and threonine186) targeted by OsMAPK6 serving an important role in modulating grain size. In addition, our genetic and molecular results suggest that the OsMAPK6-GW6a and CLG1-GW6a axes are crucial and operate in a non-additive manner to control grain size. Overall, our findings identify a previously unknown mechanism by which phosphorylation and ubiquitylation non-additively stabilize GW6a to enhance grain size, and reveal correlations and interactions of these posttranslational modifications during rice grain development.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Ubiquitinação , Oryza/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Fosforilação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Grão Comestível/metabolismo , Grão Comestível/crescimento & desenvolvimento , Processamento de Proteína Pós-Traducional , Plantas Geneticamente Modificadas , Cromatina/metabolismo
10.
J Org Chem ; 89(9): 6416-6427, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38616352

RESUMO

A novel conversion of 1,5-diynols into sulfonylated benzo[b]fluorenes is reported by a TFA-promoted cascade cyclization with sodium sulfinates under mild conditions. This strategy provides an efficient and practical approach for accessing various sulfonated benzo[b]fluorenes in moderate to excellent yields under metal-free conditions. On the basis of the control experimental results and density functional theory calculations, a possible cascade transformation mechanism consisting of the dehydration of propargylic alcohols, sulfonylation, allenylation, and Schmittel-type cyclization is proposed. It is worth noting that TFA played an important role in this cascade cyclization, which promoted C-SO2R bond cleavage in a propargylic sulfone intermediate to form allenyl sulfones, followed by Schmittel-type cyclization to give the target product.

11.
Cell Cycle ; 23(3): 262-278, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38597826

RESUMO

Esophageal cancer (EC) is a common and serious form of cancer, and while DNA methyltransferase-1 (DNMT1) promotes DNA methylation and carcinogenesis, the role of F-box protein 32 (FBXO32) in EC and its regulation by DNMT1-mediated methylation is still unclear. FBXO32 expression was examined in EC cells with high DNMT1 expression using GSE163735 dataset. RT-qPCR assessed FBXO32 expression in normal and EC cells, and impact of higher FBXO32 expression on cell proliferation, migration, and invasion was evaluated, along with EMT-related proteins. The xenograft model established by injecting EC cells transfected with FBXO32 was used to evaluate tumor growth, apoptosis, and tumor cells proliferation and metastasis. Chromatin immunoprecipitation (ChIP) assay was employed to study the interaction between DNMT1 and FBXO32. HitPredict, co-immunoprecipitation (Co-IP), and Glutathione-S-transferase (GST) pulldown assay analyzed the interaction between FBXO32 and cyclin dependent kinase 9 (CDK9). Finally, the ubiquitination assay identified CDK9 ubiquitination, and its half-life was measured using cycloheximide and confirmed through western blotting. DNMT1 negatively correlated with FBXO32 expression in esophageal cells. High FBXO32 expression was associated with better overall survival in patients. Knockdown of DNMT1 in EC cells increased FBXO32 expression and suppressed malignant phenotypes. FBXO32 repressed EC tumor growth and metastasis in mice. Enrichment of DNMT1 in FBXO32 promoter region led to increased DNA methylation and reduced transcription. Mechanistically, FBXO32 degraded CDK9 through promoting its ubiquitination.


Assuntos
Proliferação de Células , DNA (Citosina-5-)-Metiltransferase 1 , Epigênese Genética , Neoplasias Esofágicas , Proteínas F-Box , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/metabolismo , Humanos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , Animais , Proliferação de Células/genética , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Linhagem Celular Tumoral , Epigênese Genética/genética , Camundongos , Metilação de DNA/genética , Ubiquitinação , Movimento Celular/genética , Apoptose/genética , Camundongos Endogâmicos BALB C , Sobrevivência Celular/genética , Feminino , Masculino
12.
Ying Yong Sheng Tai Xue Bao ; 35(2): 407-414, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523098

RESUMO

Assessing the spatiotemporal patterns of watershed water conservation under the influence of the South Asian monsoon climate and its response to precipitation is essential for revealing the evolving patterns of water conservation under different temporal scales. Following the principles of water balance and using the Soil and Water Assessment Tool (SWAT) model, we investigated the spatiotemporal patterns of water conservation and its response to precipitation in the Fangcheng River Basin of Beibu Gulf. The results showed that water conservation in Fangcheng River Basin calculated by SWAT model were 1637.4 mm·a-1, accounting for 50.7% of the mean annual precipitation. The variation of water conservation in different sub-basins was obviously different. Sub-basins with high forest coverage and steep slopes exhibited higher water conservation, while sub-basins with other land use types (such as cropland and grassland), gentle slopes, and intense human activities showed lower water conservation. At the monthly scale, both water conservation and its variation showed similar response characteristics to precipitation in the basin. The response of water conservation variation to sub-precipitation events could be classified into two types. For the short-term rainfall events (duration≤2 days), water conservation variation showed a linear relationship. For the medium to long-term rainfall events (2 days

Assuntos
Conservação dos Recursos Hídricos , Rios , Humanos , Ecossistema , Monitoramento Ambiental , Solo , Água
13.
Nanomedicine ; 57: 102740, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458368

RESUMO

Choroidal Neovascularization (CNV) is capable of inciting recurrent hemorrhage in the macular region, severely impairing patients' visual acuity. During the onset of CNV, infiltrating M2 macrophages play a crucial role in promoting angiogenesis. To control this disease, our study utilizes the RNA interference (RNAi)-based gene therapy to reprogram M2 macrophages to the M1 phenotype in CNV lesions. We synthesize the mannose-modified siRNA-loaded liposome specifically targeting M2 macrophages to inhibit the inhibitory kappa B kinase ß (IKKß) gene involved in the polarization of macrophages, consequently modulating macrophage polarization state. In vitro and in vivo, the mannose-modified IKKß siRNA-loaded liposome (siIKKß-ML) has been proven to effectively target M2 macrophages to repolarize them to M1 phenotype, and inhibit the progression of CNV. Collectively, our findings elucidate that siIKKß-ML holds the potential to control CNV by reprogramming the macrophage phenotype, indicating a promising therapeutic avenue for CNV management.


Assuntos
Neovascularização de Coroide , Quinase I-kappa B , Humanos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Quinase I-kappa B/genética , Quinase I-kappa B/farmacologia , Lipossomos/farmacologia , Manose , Neovascularização de Coroide/genética , Macrófagos , Terapia Genética
14.
Lasers Med Sci ; 39(1): 83, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418639

RESUMO

PURPOSE: To evaluate the changes in macular structures following subthreshold micropulse laser (SHML) treatment for chronic central serous chorioretinopathy (cCSC). METHODS: Data of 33 eyes from 31 cCSC patients treated with SHML and followed up for at least 6 months has been included in this retrospective study. Main outcome measurements include resolution of subretinal fluid (SRF) and pigment epithelial detachment (PED), the recovery of ellipsoid zone (EZ) continuity, and the foveal outer nuclear layer (ONL) thickness along with its ratio. RESULTS: Mean observation period is 7.355 months (ranging from 6 to 24 months) and mean number of treatments administered is 1.839 (ranging from 1 to 5). 6 months after SHML treatment, there is a significant decrease in the area of SRF and PED (P < 0.001, P = 0.010, respectively). Additionally, the frequency of continuous EZ and the foveal ONL thickness reveal a significant increase (P<0.001, P = 0.005, respectively). The ratio of foveal ONL thickness is significantly higher after laser treatment, particularly in patients with a disease duration of ≤12 months (p = 0.022, P=0.036, respectively). CONCLUSION: SHML treatment proves to be effective in cCSC eyes, leading to satisfactory recovery of macular structures, especially the photoreceptor layer.


Assuntos
Coriorretinopatia Serosa Central , Terapia a Laser , Humanos , Coriorretinopatia Serosa Central/radioterapia , Coriorretinopatia Serosa Central/cirurgia , Estudos Retrospectivos , Angiofluoresceinografia , Acuidade Visual , Retina , Tomografia de Coerência Óptica , Doença Crônica
16.
J Agric Food Chem ; 72(7): 3814-3831, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329036

RESUMO

Common wheat (Triticum aestivum L.) is a global staple food, while nitrogen (N) limitation severely hinders plant growth, seed yield, and grain quality of wheat. Genetic variations in the responses to low N stresses among allohexaploid wheat (AABBDD, 2n = 6x = 42) genotypes emphasize the complicated regulatory mechanisms underlying low N tolerance and N use efficiency (NUE). In this study, hydroponic culture, inductively coupled plasma mass spectrometry, noninvasive microtest, high-performance liquid chromatography, RNA-seq, and bioinformatics were used to determine the differential growth performance, ionome and phytohormone profiles, and genome-wide expression profiling of wheat plants grown under high N and low N conditions. Transcriptional profiling of NPFs, NRT2s, CLCs, SLACs/SLAHs, AAPs, UPSs, NIAs, and GSs characterized the core members, such as TaNPF6.3-6D, TaNRT2.3-3D, TaNIA1-6B, TaGLN1;2-4B, TaAAP14-5A/5D, and TaUPS2-5A, involved in the efficient transport and assimilation of nitrate and organic N nutrients. The low-N-sensitivity wheat cultivar XM26 showed obvious leaf chlorosis and accumulated higher levels of ABA, JA, and SA than the low-N-tolerant ZM578 under N limitation. The TaMYB59-3D-TaNPF7.3/NRT1.5-6D module-mediated shoot-to-root translocation and leaf remobilization of nitrate was proposed as an important pathway regulating the differential responses between ZM578 and XM26 to low N. This study provides some elite candidate genes for the selection and breeding of wheat germplasms with low N tolerance and high NUE.


Assuntos
Reguladores de Crescimento de Plantas , Triticum , Triticum/genética , Triticum/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Nitrogênio/metabolismo , Nitratos/metabolismo , Melhoramento Vegetal
17.
Dev Cell ; 59(4): 448-464.e8, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38237589

RESUMO

Histone acetylation affects numerous cellular processes, such as gene transcription, in both plants and animals. However, the posttranslational modification-participated regulatory networks for crop-yield-related traits are largely unexplored. Here, we characterize a regulatory axis for controlling rice grain size and yield, centered on a potent histone acetyltransferase (chromatin modifier) known as HHC4. HHC4 interacts with and forms a ternary complex with adaptor protein ADA2 and transcription factor bZIP23, wherein bZIP23 recruits HHC4 to specific promoters, and ADA2 and HHC4 additively enhance bZIP23 transactivation on target genes. Meanwhile, HHC4 interacts with and is phosphorylated by GSK3-like kinase TGW3. The resultant phosphorylation triggers several functional impairments of the HHC4 ternary complex. In addition, we identify two major phosphorylation sites of HHC4 by TGW3-sites which play an important role in controlling rice grain size. Overall, our findings thus have critical implications for understanding epigenetic basis of grain size control and manipulating the knowledge for higher crop productivity.


Assuntos
Oryza , Animais , Fosforilação , Oryza/genética , Oryza/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cromatina/metabolismo
18.
Huan Jing Ke Xue ; 45(1): 115-122, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216463

RESUMO

Ships are important sources of carbon dioxide (CO2) emissions in Guangdong Province. The study of historical evolutions, drivers, and projected pathways of CO2 emissions can provide scientific support for the development of carbon peaking and carbon neutral strategies in Guangdong Province. The emission factor method, log-average index (LMDI) method, and scenario analysis method were adopted to estimate CO2 emissions, identify the drivers, and explore the mitigation potential from ships in Guangdong Province, separately. The results showed that:① CO2 emissions from ships in Guangdong Province increased from 3.319 4 million tons to 6.392 9 million tons from 2006 to 2020, with dry bulk carriers and container ships being the main ship types causing the increase in emissions. ② The positive drivers of CO2 emissions from ships in Guangdong Province from 2006 to 2020 were transport intensity (51%) and economic factors (49%), and the negative drivers were energy intensity (93%) and cargo class structure (7%). ③ Carbon peaking would not be reached by 2030 if Guangdong Province maintains the current policy (baseline scenario) for ship transportation. ④ Simultaneous optimization of the energy structure and promotion of the energy intensity (energy-efficient and low-carbon scenario) had a 56.51% potential to reduce CO2 emissions from ships compared to the baseline scenario. This can provide scientific support for Guangdong Province to develop a carbon peaking and carbon neutral control strategy for the shipping industry.

19.
Mol Ecol ; 33(5): e17268, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38230514

RESUMO

Ecological divergence due to habitat difference plays a prominent role in the formation of new species, but the genetic architecture during ecological speciation and the mechanism underlying phenotypic divergence remain less understood. Two wild ancestors of rice (Oryza rufipogon and Oryza nivara) are a progenitor-derivative species pair with ecological divergence and provide a unique system for studying ecological adaptation/speciation. Here, we constructed a high-resolution linkage map and conducted a quantitative trait locus (QTL) analysis of 19 phenotypic traits using an F2 population generated from a cross between the two Oryza species. We identified 113 QTLs associated with interspecific divergence of 16 quantitative traits, with effect sizes ranging from 1.61% to 34.1% in terms of the percentage of variation explained (PVE). The distribution of effect sizes of QTLs followed a negative exponential, suggesting that a few genes of large effect and many genes of small effect were responsible for the phenotypic divergence. We observed 18 clusters of QTLs (QTL hotspots) on 11 chromosomes, significantly more than that expected by chance, demonstrating the importance of coinheritance of loci/genes in ecological adaptation/speciation. Analysis of effect direction and v-test statistics revealed that interspecific differentiation of most traits was driven by divergent natural selection, supporting the argument that ecological adaptation/speciation would proceed rapidly under coordinated selection on multiple traits. Our findings provide new insights into the understanding of genetic architecture of ecological adaptation and speciation in plants and help effective manipulation of specific genes or gene cluster in rice breeding.


Assuntos
Oryza , Oryza/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Fenótipo , Locos de Características Quantitativas/genética
20.
Nanoscale ; 16(6): 3061-3070, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38240625

RESUMO

Physical reservoirs employed to map time-series data and analyze extracted features have attracted interest owing to their low training cost and mitigated interconnection complexity. This study reports a physical reservoir based on a bilayer oxide-based dynamic memristor. The proposed device exhibits a nonlinear current response and short-term memory (STM), satisfying the requirements of reservoir computing (RC). These characteristics are validated using a compact model to account for resistive switching (RS) via the dynamic evolution of the internal state variable and the relocation of oxygen vacancies. Mathematically, the transient current response can be quantitatively described according to a simple set of equations to correlate the theoretical framework with experimental results. Furthermore, the device shows significant reliability and ability to distinguish 4-bit inputs and four diverse neural firing patterns. Therefore, this work shows the feasibility of implementing physical reservoirs in hardware and advances the understanding of the dynamic response.

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