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1.
Theor Appl Genet ; 137(1): 18, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38206376

RESUMO

KEY MESSAGE: Eleven QTLs for agronomic traits were identified by RTM- and MLM-GWAS, putative candidate genes were predicted and two markers for grain weight were developed and validated. Foxtail millet (Setaria italica), the second most cultivated millet crop after pearl millet, is an important grain crop in arid regions. Seven agronomic traits of 408 diverse foxtail millet accessions from 15 provinces in China were evaluated in three environments. They were clustered into two divergent groups based on genotypic data using ADMIXTURE, which was highly consistent with their geographical distribution. Two models for genome-wide association studies (GWAS), namely restricted two-stage multi-locus multi-allele (RTM)-GWAS and mixed linear model (MLM)-GWAS, were used to dissect the genetic architecture of the agronomic traits based on 13,723 SNPs. Eleven quantitative trait loci (QTLs) for seven traits were identified using two models (RTM- and MLM-GWAS). Among them, five were considered stable QTLs that were identified in at least two environments using MLM-GWAS. One putative candidate gene (SETIT_006045mg, Chr4: 744,701-746,852) that can enhance grain weight per panicle was identified based on homologous gene comparison and gene expression analysis and was validated by haplotype analysis of 330 accessions with high-depth (10×) resequencing data (unpublished). In addition, homologous gene comparison and haplotype analysis identified one putative foxtail millet ortholog (SETIT_032906mg, Chr2: 5,020,600-5,029,771) with rice affecting the target traits. Two markers (cGWP6045 and kTGW2906) were developed and validated and can be used for marker-assisted selection of foxtail millet with high grain weight. The results provide a fundamental resource for foxtail millet genetic research and breeding and demonstrate the power of integrating RTM- and MLM-GWAS approaches as a complementary strategy for investigating complex traits in foxtail millet.


Assuntos
Setaria (Planta) , Setaria (Planta)/genética , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Melhoramento Vegetal , Fenótipo , Grão Comestível
2.
Theor Appl Genet ; 137(8): 186, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017920

RESUMO

KEY MESSAGE: One hundred and fifty-five QTL for trace element concentrations in foxtail millet were identified using a genome-wide association study, and a candidate gene associated with Ni-Co-Cr concentrations was detected. Foxtail millet (Setaria italica) is an important regional crop known for its rich mineral nutrient content, which has beneficial effects on human health. We assessed the concentrations of ten trace elements (Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, and Zn) in the grain of 408 foxtail millet accessions. Significant differences in the concentrations of five elements (Ba, Co, Ni, Sr, and Zn) were observed between two subpopulations of spring- and summer-sown foxtail millet varieties. Moreover, 84.4% of the element pairs exhibited significant correlations. To identify the genetic factors influencing trace element accumulation, a comprehensive genome-wide association study was conducted, identifying 155 quantitative trait locus (QTL) for the ten trace elements across three different environments. Among them, ten QTL were consistently detected in multiple environments, including qZn2.1, qZn4.4, qCr4.1, qFe6.3, qFe6.5, qCo6.1, qPb7.3, qPb7.5, qBa9.1, and qNi9.1. Thirteen QTL clusters were detected for multiple elements, which partially explained the correlations between elements. Additionally, the different concentrations of five elements between foxtail millet subpopulations were caused by the different frequencies of high-concentration alleles associated with important marker-trait associations. Haplotype analysis identified a candidate gene SETIT_036676mg associated with Ni accumulation, with the GG haplotype significantly increasing Ni-Co-Cr concentrations in foxtail millet. A cleaved amplified polymorphic sequence marker (cNi6676) based on the two haplotypes of SETIT_036676mg was developed and validated. Results of this study provide valuable reference information for the genetic research and improvement of trace element content in foxtail millet.


Assuntos
Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Setaria (Planta) , Oligoelementos , Setaria (Planta)/genética , Oligoelementos/análise , Mapeamento Cromossômico , Fenótipo , Polimorfismo de Nucleotídeo Único , Genótipo
3.
Mol Cell Biochem ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254871

RESUMO

Pulmonary hypertension (PH) is heterogeneous diseases that can lead to death due to progressive right heart failure. Emerging evidence suggests that, in addition to its role in ATP production, changes in mitochondrial play a central role in their pathogenesis, regulating integrated metabolic and signal transduction pathways. This review focuses on the basic principles of mitochondrial redox status in pulmonary vascular and right ventricular disorders, a series of dysfunctional processes including mitochondrial quality control (mitochondrial biogenesis, mitophagy, mitochondrial dynamics, mitochondrial unfolded protein response) and mitochondrial redox homeostasis. In addition, we will summarize how mitochondrial renewal and dynamic changes provide innovative insights for studying and evaluating PH. This will provide us with a clearer understanding of the initial signal transmission of mitochondria in PH, which would further improve our understanding of the pathogenesis of PH.

4.
Lupus ; 33(3): 255-265, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38269543

RESUMO

PURPOSE: To explore the relationship between brain function changes and clinical serological indicators and behavioral cognitive assessment in patients with neuropsychiatric systemic lupus erythematosus (NPSLE), and understand the pathogenesis of NPSLE from the perspective of imaging. METHODS: The resting-state functional imaging data, clinical serological, and behavioral cognitive assessment scores of 28 patients with NPSLE and 22 healthy controls (HC) were prospectively collected. The resting-state amplitude of low-frequency fluctuation (ALFF) values obtained from the analysis and processing were correlated with the serological data and behavioral cognitive assessment scores to determine the relationship between these data. RESULTS: The average age of the patients of the NPSLE group was older than that of the HC group; significant differences in education level, Auditory Verbal Learning Test Hua Shan Version (AVLT-H), and Trail Making Test scores were observed between the two groups. The NPSLE group demonstrated increased brain activity in the insula, precentral gyrus, and superior temporal gyrus, and decreased brain activity in the superior parietal gyrus. The ALFF value of the insula positively correlated with the Anti-ß2gp1 antibody and negatively correlated with the anti-nucleosome antibody and the AVL-recall (RC) score. The ALFF of the precentral gyrus negatively correlated with the AVL-immediate recall (I). The ALFF value of the superior temporal gyrus negatively correlated with the AVL-RC score. The left superior parietal gyrus positively correlated with the c-reactive protein. The right superior parietal gyrus positively correlated with the System Lupus Erythematosus Disease Activity Index and negatively correlated with the AVL-I score. CONCLUSION: Patients with NPSLE show different brain activity changes in different brain regions, and the abnormal brain regions are correlated with certain lupus antibodies, inflammatory factors, and cognitive assessment, thereby suggesting that the correlation between the three could provide novel insights into the pathogenesis of NPSLE.


Assuntos
Disfunção Cognitiva , Lúpus Eritematoso Sistêmico , Vasculite Associada ao Lúpus do Sistema Nervoso Central , Humanos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia
5.
Plant Physiol ; 189(4): 2144-2158, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35512195

RESUMO

The cuticle, a hydrophobic layer of cutin and waxes synthesized by plant epidermal cells, is the major barrier to water loss when stomata are closed. Dissecting the genetic architecture of natural variation for maize (Zea mays L.) leaf cuticular conductance (gc) is important for identifying genes relevant to improving crop productivity in drought-prone environments. To this end, we performed an integrated genome- and transcriptome-wide association studies (GWAS and TWAS) to identify candidate genes putatively regulating variation in leaf gc. Of the 22 plausible candidate genes identified, 4 were predicted to be involved in cuticle precursor biosynthesis and export, 2 in cell wall modification, 9 in intracellular membrane trafficking, and 7 in the regulation of cuticle development. A gene encoding an INCREASED SALT TOLERANCE1-LIKE1 (ISTL1) protein putatively involved in intracellular protein and membrane trafficking was identified in GWAS and TWAS as the strongest candidate causal gene. A set of maize nested near-isogenic lines that harbor the ISTL1 genomic region from eight donor parents were evaluated for gc, confirming the association between gc and ISTL1 in a haplotype-based association analysis. The findings of this study provide insights into the role of regulatory variation in the development of the maize leaf cuticle and will ultimately assist breeders to develop drought-tolerant maize for target environments.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Folhas de Planta/metabolismo , Transcriptoma , Ceras/metabolismo , Zea mays/metabolismo
6.
Proc Natl Acad Sci U S A ; 117(22): 12464-12471, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32424100

RESUMO

Plant cuticles are composed of wax and cutin and evolved in the land plants as a hydrophobic boundary that reduces water loss from the plant epidermis. The expanding maize adult leaf displays a dynamic, proximodistal gradient of cuticle development, from the leaf base to the tip. Laser microdissection RNA Sequencing (LM-RNAseq) was performed along this proximodistal gradient, and complementary network analyses identified potential regulators of cuticle biosynthesis and deposition. A weighted gene coexpression network (WGCN) analysis suggested a previously undescribed function for PHYTOCHROME-mediated light signaling during the regulation of cuticular wax deposition. Genetic analyses reveal that phyB1 phyB2 double mutants of maize exhibit abnormal cuticle composition, supporting the predictions of our coexpression analysis. Reverse genetic analyses also show that phy mutants of the moss Physcomitrella patens exhibit abnormal cuticle composition, suggesting an ancestral role for PHYTOCHROME-mediated, light-stimulated regulation of cuticle development during plant evolution.


Assuntos
Folhas de Planta/crescimento & desenvolvimento , Transcriptoma , Zea mays/genética , Bryopsida/genética , Bryopsida/metabolismo , Bryopsida/efeitos da radiação , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma/efeitos da radiação , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Zea mays/efeitos da radiação
7.
Ann Bot ; 125(1): 79-91, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31504131

RESUMO

BACKGROUND AND AIMS: Prior work has examined cuticle function, composition and ultrastructure in many plant species, but much remains to be learned about how these features are related. This study aims to elucidate relationships between these features via analysis of cuticle development in adult maize (Zea mays L.) leaves, while also providing the most comprehensive investigation to date of the composition and ultrastructure of adult leaf cuticles in this important crop plant. METHODS: We examined water permeability, wax and cutin composition via gas chromatography, and ultrastructure via transmission electron microscopy, along the developmental gradient of partially expanded adult maize leaves, and analysed the relationships between these features. KEY RESULTS: The water barrier property of the adult maize leaf cuticle is acquired at the cessation of cell expansion. Wax types and chain lengths accumulate asynchronously over the course of development, while overall wax load does not vary. Cutin begins to accumulate prior to establishment of the water barrier and continues thereafter. Ultrastructurally, pavement cell cuticles consist of an epicuticular layer, and a thin cuticle proper that acquires an inner, osmiophilic layer during development. CONCLUSIONS: Cuticular waxes of the adult maize leaf are dominated by alkanes and alkyl esters. Unexpectedly, these are localized mainly in the epicuticular layer. Establishment of the water barrier during development coincides with a switch from alkanes to esters as the major wax type, and the emergence of an osmiophilic (likely cutin-rich) layer of the cuticle proper. Thus, alkyl esters and the deposition of the cutin polyester are implicated as key components of the water barrier property of adult maize leaf cuticles.


Assuntos
Água , Zea mays , Epiderme Vegetal , Folhas de Planta , Ceras
8.
Opt Express ; 27(3): 1798-1807, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732227

RESUMO

The wavelength tuning range of a tunable vertical-cavity surface-emitting laser (VCSEL) is strongly influenced by the design of the interface between the semiconductor cavity and the air cavity. A simplified model is used to investigate the origin of the dramatic differences in free spectral range (FSR) and tuning slope observed in semiconductor cavity dominant, extended cavity, and air cavity dominant VCSELs. The differences arise from the positioning of the resonant and antiresonant wavelengths of the semiconductor cavity with respect to the center wavelength. The air cavity dominant design is realized by designing an antiresonant semiconductor cavity, resulting in a larger tuning slope near the center of the tuning range and a wider FSR toward the edges of the tuning range. The findings from the simplified model are confirmed with the simulation of a full VCSEL structure. Using an air cavity dominant design, an electrically pumped laser with a tuning range of 68.38 nm centered at 1056.7 nm at a 550 kHz sweep rate is demonstrated with continuous wave emission at room temperature. This epitaxial design rule can be used to increase the tuning range of tunable VCSELs, making them more applicable in swept-source optical coherence tomography and frequency-modulated continuous-wave LIDAR systems.

9.
Clin Transplant ; 33(10): e13677, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31342552

RESUMO

BACKGROUND: This study aimed to explore the safety of donors with primary central nervous system tumors for kidney and liver transplantations. METHODOLOGY: Clinical data of 29 donors with primary CNS tumors in January 2007 to December 2017, as well as the follow-up data of 16 liver transplant recipients and 46 kidney transplant recipients, were analyzed. According to the risk factors, the high-risk group was classified as Group 1, the low-risk factors were classified as Group 2, and the unknown risk group was classified as Group 3. The incidence of donor-transmitted CNS tumors was calculated and compared. RESULTS: The duration from the diagnosis of 29 donors to donation was 5.67 ± 6.36 months. None of the liver and kidney transplant recipients who were followed up had tumor metastasis. Although the mean survival time of Group 1 was lower than that of Group 2 and Group 3, the Kaplan-Meier curve showed no significant difference in survival time. CONCLUSION: No obvious difference was observed between high-risk and low-risk and unknown risk CNS tumors in terms of the survival rate of transplants and tumor metastasis rate. High-risk CNS tumor donors can be used with the informed consent of recipients after a full evaluation.


Assuntos
Neoplasias do Sistema Nervoso Central/patologia , Transplante de Rim/mortalidade , Transplante de Fígado/mortalidade , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adolescente , Adulto , Neoplasias do Sistema Nervoso Central/terapia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Adulto Jovem
10.
Chin J Cancer Res ; 30(4): 425-431, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30210222

RESUMO

OBJECTIVE: In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis were quantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to assess the value of DCE-MRI in the differential diagnosis of these diseases. METHODS: Patients with brucellar spondylitis, spinal tuberculosis or a spinal metastatic tumor (30 cases of each) received conventional MRI and DCE-MRI examination. The volume transfer constant (Ktrans), rate constant (Kep), extravascular extracellular volume fraction (Ve) and plasma volume fraction (Vp) of the diseased vertebral bodies were measured on the perfusion parameter map, and the differences in these parameters between the patients were compared. RESULTS: For pathological vertebrae in cases of spinal metastatic tumor, brucellar spondylitis and spinal tuberculosis, respectively, the Ktrans values (median ± quartile pitch) were 0.989±0.014, 0.720±0.011 and 0.317±0.005 min-1; the Kep values were 2.898±0.055, 1.327±0.017 and 0.748±0.006 min-1; the Ve values were 0.339±0.008, 0.542±0.013 and 0.428±0.018; the Vp values were 0.048±0.008, 0.035±0.004 and 0.028±0.009; the corresponding H values were 50.25 (for Ktrans), 52.47 (for Kep), 48.33 (for Ve) and 46.56 (for Vp), and all differences were statistically significant (two-sided P<0.05). CONCLUSIONS: The quantitative analysis of DCE-MRI has a certain value in the differential diagnosis of spinal metastatic tumor, brucellar spondylitis and spinal tuberculosis.

11.
Opt Express ; 25(10): 11844-11854, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788744

RESUMO

We report tunable VCSELs emitting around 1060 nm, enabled by high-contrast grating (HCG) mirror. Single-mode continuous-wave (CW) operation up to 110 °C is demonstrated, with room-temperature single-mode output power >1.3 mW at a very low threshold of ~300 µA. The obtained thermal resistance of 0.88 °C/mW is low for VCSELs with an oxide-confined laser aperture. A wide, continuous tuning range up to 40 nm was achieved with electrostatic and thermal tuning, at a fast tuning speed up to 1.15 MHz. In addition, we developed transverse-mode control designs of HCGs to greatly improve the single-mode yield of oxidized VCSELs. The cost-effective, wafer-scale fabrication makes these VCSELs promising as tunable light sources for swept-source optical coherent tomography (SS-OCT) and LiDAR applications.

12.
Opt Lett ; 42(4): 823-826, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198874

RESUMO

We demonstrate the room-temperature operation of a two-dimensional (2D) high-contrast grating (HCG) vertical-cavity surface-emitting laser (VCSEL) at 1080 nm. To the best of our knowledge, this is the first tunable electrically pumped surface-emitting laser using a 2D HCG. Our theory successfully explains the mechanism of broadband ultrahigh reflection of 2D HCGs. Our monolithic integrated laser exhibits single-mode output power above 0.68 mW under continuous-wave operation. Wavelength tunability is demonstrated via microelectromechanical system-controlled voltage.

13.
Neurosciences (Riyadh) ; 22(4): 316-319, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29057860

RESUMO

OBJECTIVE: To detect resting-state functional MRI (rsfMRI) changes and their relationships with the clinical curative effect of anti-epileptic drugs (AEDs) for complex partial seizures (CPS) in epilepsy patients using the fractional amplitude of low frequency fluctuation (fALFF). METHODS: rfMRI data from 14 CPS patients enrolled between June 2015 and June 2016 in Department of Neurology, Affiliated Hospital of Inner Mongolia Medical University were retrospectively investigated and compared with findings from 14 healthy age-, gender-, handedness-, and education-matched subjects. The patients were treated with first-line antiepileptic drugs for 12 weeks before undergoing a second rfMRI scan. fALFF data were processed using REST and SPM8 software. Whole-brain data were compared between the 2 groups. RESULTS: The abnormal findings in CPS patients significantly decreased or disappeared after AED treatment. CONCLUSION: Measuring fALFF is useful for identifying brain functional changes in patients with first-episode epilepsy before and after treatment. Performing rfMRI is useful for evaluating treatment responses and may provide new insight into the pathophysiological mechanisms of epilepsy.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/diagnóstico por imagem , Epilepsia/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Descanso , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Criança , Eletroencefalografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Oxigênio/sangue , Estudos Retrospectivos , Adulto Jovem
14.
Opt Express ; 23(19): 24508-24, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26406655

RESUMO

Optical properties of two-dimensional (2D) high-contrast gratings are investigated. We analyze the mechanisms for high-contrast gratings to function as various high-performance optical components. Our top-down design procedure allows us to efficiently obtain initial structural parameters and engineer them for a wide range of applications, such as reflectors, filters, resonators, waveplates, and even 2D phase plates. Simulation results of our designed structures show ultra-high power efficiency, and excellent agreement with our predicted functionalities.

15.
Opt Express ; 23(3): 2512-23, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836117

RESUMO

We report an electrically pumped hybrid cavity AlGaInAs-silicon long-wavelength VCSEL using a high contrast grating (HCG) reflector on a silicon-on-insulator (SOI) substrate. The VCSEL operates at silicon transparent wavelengths ~1.57 µm with >1 mW CW power outcoupled from the semiconductor DBR, and single-mode operation up to 65 °C. The thermal resistance of our device is measured to be 1.46 K/mW. We demonstrate >2.5 GHz 3-dB direct modulation bandwidth, and show error-free transmission over 2.5 km single mode fiber under 5 Gb/s direct modulation. We show a theoretical design of SOI-HCG serving both as a VCSEL reflector as well as waveguide coupler for an in-plane SOI waveguide, facilitating integration of VCSEL with in-plane silicon photonic circuits. The novel HCG-VCSEL design, which employs scalable flip-chip eutectic bonding, may enable low cost light sources for integrated optical links.

16.
BMC Cancer ; 15: 469, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26077733

RESUMO

BACKGROUND: Extrahepatic Cholangiocarcinoma (EHCC) is one of the uncommon malignancies in the digestive system which is characterized by a poor prognosis. Aberrations of miRNAs have been shown involved in the progression of this disease. In this study, we evaluated the expression and effects of miR-34a on EHCC. METHODS: miR-34a expression levels were detected in EHCC tissues, adjacent non-tumor tissues, normal bile duct (NBD) specimens of patients and cholangiocarcinoma (CC) cell lines by quantitative real-time polymerase chain reaction (qRT-PCR). Relationships between miR-34a with clinical characteristics of EHCC patients were further analyzed. Computational search, functional luciferase assay and western blot were further used to demonstrate the downstream target of miR-34a in CC cells. Immunohistochemistry was carried on to identify the downstream target gene of miR-34a in EHCC patients. Cell morphology, invasion and migration assays were further applied to confirm the anti-carcinogenic effects of miR-34a through the downstream target. RESULTS: miR-34a expression was significantly decreased in human EHCC tissues and CC cell lines when compared with the adjacent non-tumor tissues and normal bile duct tissues. miR-34a was found correlated with the migration and invasion in EHCC patients. Smad4 was over-expressed in most of the EHCC patients and was further demonstrated as one of the downstream targets of miR-34a, which was involved in the progression of EHCC. Moreover, activation of miR-34a suppressed invasion and migration through TGF-beta/Smad4 signaling pathway by epithelial-mesenchymal transition (EMT) in vitro. CONCLUSIONS: Taken together, our results suggest that miR-34a inhibits invasion and migration by targeting Smad4 to suppress EMT through TGF- beta/Smad signaling pathway in human EHCC.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Transição Epitelial-Mesenquimal/genética , MicroRNAs/metabolismo , Proteína Smad4/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Neoplasias dos Ductos Biliares/genética , Linhagem Celular Tumoral , Colangiocarcinoma/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Transdução de Sinais , Proteína Smad4/genética
17.
Opt Express ; 22(7): 8541-55, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24718226

RESUMO

A comprehensive theoretical model for the long-wavelength micro-electro-mechanical-tunable high-contrast-grating vertical-cavity surface-emitting lasers is presented. Our band structure model calculates the optical gain and spontaneous emission of the InGaAlAs quantum well active region. The grating reflectivity and the cavity resonance condition are investigated through optical modeling. Correlating the results with the electrostatic model for the micro-electro-mechanical system, we accurately predict the measurements on the voltage-contolled lasing wavelength. Furthermore, our calculated temperature-dependent wavelength-tunable light output vs. current (L-I) curves show excellent agreement with experiment.

18.
Aging Clin Exp Res ; 26(2): 123-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24129805

RESUMO

BACKGROUND AND AIMS: The information about clinical presentation and outcome of elderly hepatocellular carcinoma (HCC) patients is limited. We performed this study to assess the impact of age on potential differences in clinical characteristics, treatment patterns and outcome in HCC patients. METHODS: Clinical data of 164 "elderly" (≥70 years old) and 531 "younger" (<70 years old) HCC patients treated at a Chinese tertiary university-affiliated medical center between April 2004 and April 2012 were collected and compared using various parameters. RESULTS: Compared with younger patients, the elderly patients had a higher proportion of females (32.9 % vs. 18.1 %, p < 0.001), less hepatitis B virus (HBV) infection (40.9 % vs. 76.6 %, p < 0.001), more hepatitis C virus (HCV) infection (23.8 % vs. 5.6 %, p < 0.001), less liver cirrhosis (68.3 % vs. 76.8 %, p = 0.03) and massive tumors (12.8 % vs. 21.8 %, p = 0.01). There was no significant difference between the two groups in Child-Pugh class and tumor stages. The elderly patients received less surgical resection (14.6 % vs. 29.6 %, p < 0.001) and more supportive care (48.8 % vs. 37.9 %, p = 0.01) than younger patients. The overall survival was not significantly different between the two groups (26.2 mo. vs. 28.3 mo., p = 0.75). CONCLUSION: Characteristics that distinguish elderly from younger HCC patients included more female, less HBV infection, more HCV infection, less liver cirrhosis and massive tumors. Significant differences were observed in therapeutic strategies utilized with the two groups, but the overall survival was not significantly different.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Adulto , Fatores Etários , Idoso , Carcinoma Hepatocelular/mortalidade , China/epidemiologia , Comorbidade , Feminino , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/patologia , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
19.
Front Plant Sci ; 15: 1419437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290745

RESUMO

Introduction: Wheat (Triticum aestivum L.) is among themost important crop worldwide. Given a growing population and changing climate, enhancing wheat yield is of great importance. Yield is closely associated with flower and spike development, and E-class genes play important roles in the flower and kernel development of plants. Currently, the absence of systematic analysis on the E gene family hinders our comprehension of their roles in plant growth and development. Methods: Identify E-class genes based on homologous sequence searches. Analyze the identified E-class genes through a series of gene family analyses. Determine the expression levels of wheat E-class genes by searching public databases. Validate the functions of these genes by transforming them into Arabidopsis. Finally, determine the interactions between the genes through yeast two-hybrid experiments. Results: Fifteen E-class genes (TaEs) were identified in common wheat. Nine E-class genes were detected in five ancestral/closely related species, including one in Aegilops tauschii (AtE), one in T. Urartu (TuEs), two in T. turgidum (TtEs), two in T. dicoccoides (TdEs), and three in T. spelta (TsEs). The 24 E-class genes were classified into three subgroups using a phylogenetic approach. All genes were highly expressed in spikes, and most were only highly expressed at the floret meristem stage. The effects of TaSEP5-A on flowering and growth cycles were confirmed in homologous mutants and transgenic Arabidopsis thaliana. The E-class genes were able to regulate the growth cycle of Arabidopsis. Finally, we confirmed the interactions between TaSEP5-A and other wheat E-class genes based on yeast two-hybrid assays. Discussion: Our findings provide information regarding the E-class genes in wheat and will potentially promote the application of these genes in wheat improvement.

20.
J Phys Chem Lett ; 15(36): 9301-9310, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39235319

RESUMO

The development of monolithic integrated energy-efficient complementary circuits is crucial for the large-scale application of wide bandgap semiconductor-based high-frequency and high-power field-effect transistors (FETs). However, the inferior performance of p-channel FETs attributed to low hole density and mobility presents a substantial challenge. Diamond is a promising candidate due to its excellent comprehensive electrical properties and high thermal conductivity. Here, we report the fabrication of normally off diamond FETs based on a low work function metal gate and (110) hydrogen-terminated diamond with high hole density. The use of high-quality SiO2 layer ensures the complete depletion of the channel by the gate and offers high gating efficiency. Therefore, the developed devices demonstrate exceptional reproducibility of normally off characteristics with centrally distributed threshold voltages (-0.37 ± 0.3 V) and realize large current and voltage handling capabilities and low static standby power consumption in a synergic manner with record-high on/off ratio exceeding 1010, high current density (∼200 µA·µm-1), ultralow off-state current (∼fA·µm-1), and high breakdown voltage (-676 V). Additionally, the thermal desorption of negatively charged acceptors has been proven to significantly reduce carrier scattering. This work offers superior performance p-channel FETs for implementing energy-efficient complementary circuits, laying the groundwork for accelerated development in wide bandgap semiconductor power electronics.

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