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1.
Neuropathology ; 44(2): 87-95, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37469134

RESUMO

The mutations of the feline leukemia virus subgroup C receptor-related protein 1 (FLVCR1) cause ataxia with retinitis pigmentosa. Recent studies indicated a large variation in the phenotype of FLVCR1-associated diseases. In this report, we describe an adult male who manifested first with tremors in his third decade, followed by retinitis pigmentosa, sensory ataxia, and sensory neuropathy in his fourth decade. While retinitis pigmentosa and sensory ataxia are well-recognized features of FLVCR1-associated disease, tremor is rarely described. Whole-exome sequencing revealed novel compound heterozygous pathogenic FLVCR1 variants: c.498 G > A; p.(Trp166*) and c.369 T > G; p.(Phe123Leu). In addition, we have highlighted the ultrastructural abnormalities of the sural biopsy in this patient.


Assuntos
Doenças do Sistema Nervoso Periférico , Retinose Pigmentar , Adulto , Humanos , Masculino , Ataxia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Receptores Virais/genética , Receptores Virais/metabolismo , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo , Tremor
2.
Int J Mol Sci ; 24(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37175772

RESUMO

Burkholderia pyrrocinia JK-SH007 can effectively control poplar canker caused by pathogenic fungi. Its antifungal mechanism remains to be explored. Here, we characterized the functional role of CysB in B. pyrrocinia JK-SH007. This protein was shown to be responsible for the synthesis of cysteine and the siderophore ornibactin, as well as the antifungal activity of B. pyrrocinia JK-SH007. We found that deletion of the cysB gene reduced the antifungal activity and production of the siderophore ornibactin in B. pyrrocinia JK-SH007. However, supplementation with cysteine largely restored these two abilities in the mutant. Further global transcriptome analysis demonstrated that the amino acid metabolic pathway was significantly affected and that some sRNAs were significantly upregulated and targeted the iron-sulfur metabolic pathway by TargetRNA2 prediction. Therefore, we suggest that, in B. pyrrocinia JK-SH007, CysB can regulate the expression of genes related to Fe-S clusters in the iron-sulfur metabolic pathway to affect the antifungal activity of B. pyrrocinia JK-SH007. These findings provide new insights into the various biological functions regulated by CysB in B. pyrrocinia JK-SH007 and the relationship between iron-sulfur metabolic pathways and fungal inhibitory substances. Additionally, they lay the foundation for further investigation of the main antagonistic substances of B. pyrrocinia JK-SH007.


Assuntos
Complexo Burkholderia cepacia , Burkholderia , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Sideróforos/farmacologia , Sideróforos/metabolismo , Cisteína/metabolismo , Burkholderia/genética , Complexo Burkholderia cepacia/metabolismo , Ferro/metabolismo , Enxofre/metabolismo , Proteínas de Bactérias/metabolismo
3.
Plant Biotechnol J ; 20(6): 1213-1225, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35258157

RESUMO

Postharvest deterioration is among the major challenges for the fruit industry. Regulation of the fruit softening rate is an effective strategy for extending shelf-life and reducing the economic losses due postharvest deterioration. The tomato myoinositol monophosphatase 3 gene SlIMP3, which showed highest expression level in fruit, was expressed and purified. SlIMP3 demonstrated high affinity with the L-Gal 1-P and D-Ins 3-P, and acted as a bifunctional enzyme in the biosynthesis of AsA and myoinositol. Overexpression of SlIMP3 not only improved AsA and myoinositol content, but also increased cell wall thickness, improved fruit firmness, delayed fruit softening, decreased water loss, and extended shelf-life. Overexpression of SlIMP3 also increased uronic acid, rhamnose, xylose, mannose, and galactose content in cell wall of fruit. Treating fruit with myoinositol obtained similar fruit phenotypes of SlIMP3-overexpressed fruit, with increased cell wall thickness and delayed fruit softening. Meanwhile, overexpression of SlIMP3 conferred tomato fruit tolerance to Botrytis cinerea. The function of SlIMP3 in cell wall biogenesis and fruit softening were also verified using another tomato species, Ailsa Craig (AC). Overexpression of SlDHAR in fruit increased AsA content, but did not affect the cell wall thickness or fruit firmness and softening. The results support a critical role for SlIMP3 in AsA biosynthesis and cell wall biogenesis, and provide a new method of delaying tomato fruit softening, and insight into the link between AsA and cell wall metabolism.


Assuntos
Solanum lycopersicum , Ácido Ascórbico , Parede Celular/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Inositol/metabolismo , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Clin Neuropathol ; 41(5): 202-210, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603692

RESUMO

OBJECTIVE: Spinocerebellar ataxia with axonal neuropathy type 3 (SCAN3) is a very rare autosomal recessive hereditary disease. Mutations in the COA7 gene, which encodes cytochrome c oxidase assembly factor 7, have been recently reported as the causative gene of SCAN3. So far, only five SCAN3 patients with COA7 mutations have been documented. Herein, we report the clinical, electrophysiological, histological, and genetic findings of a Chinese patient with SCAN3. MATERIALS AND METHODS: The patient was a 31-year-old woman who presented with early-onset peripheral neuropathy and progressive ataxia. She was asked about her medical history and underwent electrophysiological examination, nerve and muscle biopsy, and gene detection. RESULTS: Whole exome next-generation sequencing identified a novel compound heterozygous mutation of COA7 (c.17A>G p.D6G; c.554G>A, p.W185*) in this patient. Magnetic resonance imaging showed cerebellum and spinal cord atrophy. Nerve conduction studies and sural nerve biopsies revealed sensorimotor axonal neuropathy. Muscle biopsies showed mitochondrial abnormalities. Respiratory chain enzyme assay of skin fibroblasts showed normal respiratory chain complex activities. Additionally, the clinical data on previously reported SCAN patients with identified genetic causes in PubMed was summarized. Compared with SCAN1 and SCAN2 patients, SCAN3 patients had earlier onset age, less cognitive impairment, and no ocular signs. CONCLUSION: We reported the first patient diagnosed with SCAN3 in China. A novel mutation in the gene COA7 (c.554G>A, p.W185*) expanded the genetic spectrum of the disease.


Assuntos
Doenças do Sistema Nervoso Periférico , Ataxias Espinocerebelares , Adulto , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fator VII/genética , Feminino , Humanos , Mutação , Linhagem , Doenças do Sistema Nervoso Periférico/genética , Ataxias Espinocerebelares/genética
5.
Plant Biotechnol J ; 19(1): 138-152, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32654333

RESUMO

Unicellular and multicellular tomato trichomes function as mechanical and chemical barriers against herbivores. Auxin treatment increased the formation of II, V and VI type trichomes in tomato leaves. The auxin response factor gene SlARF4, which was highly expressed in II, V and VI type trichomes, positively regulated the auxin-induced formation of II, V and VI type trichomes in the tomato leaves. SlARF4 overexpression plants with high densities of these trichomes exhibited tolerance to spider mites. Two R2R3 MYB genes, SlTHM1 and SlMYB52, were directly targeted and inhibited by SlARF4. SlTHM1 was specifically expressed in II and VI type trichomes and negatively regulated the auxin-induced formation of II and VI type trichomes in the tomato leaves. SlTHM1 down-regulation plants with high densities of II and VI type trichomes also showed tolerance to spider mites. SlMYB52 was specifically expressed in V type trichomes and negatively regulated the auxin-induced formation of V type trichome in the tomato leaves. The regulation of SlARF4 on the formation of II, V and VI type trichomes depended on SlTHM1 and SlMYB52, which directly targeted cyclin gene SlCycB2 and increased its expression. In conclusion, our data indicates that the R2R3 MYB-dependent auxin signalling pathway regulates the formation of II, V and VI type trichomes in tomato leaves. Our study provides an effective method for improving the tolerance of tomato to spider mites.


Assuntos
Solanum lycopersicum , Tetranychidae , Animais , Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos , Solanum lycopersicum/genética , Folhas de Planta/genética , Tetranychidae/genética , Tricomas
6.
J Environ Sci (China) ; 86: 187-194, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787183

RESUMO

Enzymatic electrolysis cell (EEC) has advantages over microbial electrolysis cell (MEC) due to the needless of microbe inoculation and high-efficiency of enzymatic reaction. In this study, an EEC was first applied to achieve the effective degradation of halogenated organic pollutants and dichloromethane (CH2Cl2) was utilized as a model pollutant. The results indicate that the degradation efficiency of CH2Cl2 after 2 hr reaction in the EEC was almost 100%, which was significantly higher than that with enzyme (51.1%) or current (19.0%). The current induced the continuous regeneration of reduced glutathione (GSH), thus CH2Cl2 was degraded under the catalysis of GSH-dependent dehalogenase through stepwise dechlorination, and successively formed monochloromethane (CH3Cl) and methane (CH4). The kinetic result shows that with a current of 15 mA, the maximum specific degradation rate of CH2Cl2 (3.77 × 10-3hr-1) was increased by 5.7 times. The optimum condition for CH2Cl2 dechlorination was also obtained with pH, current and temperature of 7.0, 15 mA and 35°C, respectively. Importantly, this study helps to understand the behavior of enzymes and the fate of halogenated organic pollutants with EEC, providing a possible treatment technology for halogenated organic pollutants.


Assuntos
Cloreto de Metileno/química , Biodegradação Ambiental , Catálise , Eletrólise , Eletrólitos , Cinética , Metano
7.
Biochem Biophys Res Commun ; 496(2): 502-507, 2018 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-29339154

RESUMO

Infection with hepatitis B virus (HBV) e-antigen (HBeAg)-negative strains is increasingly prevalent. Currently, detailed information of the obtained natural HBV strain is not available except for the B genotype and HBeAg-negative. The aim of the present study was to characterize the natural genetic variation of the HBeAg-negative strain and investigate its function. The genic sequence was determined using Sanger sequencing, and compared to related sequences using alignment and phylogenetic analysis. In vivo, virus-specific serum markers were investigated in CBA/CaJ mice. The sequence had a full genome length of 3215 nucleotides. Sites 122, 125, 127, and 160 in S regions were identified as lysine, threonine, proline, and lysine respectively. The main four point variants including A1762T, G1764A, G1896A, and G1899A were detected in the full-length genome. The genotype of the sequence was B, with sub-genotype B2 and serological subtype adw2. The characterize of the natural genetic variation strain showed no reported drug-resistant variant in P region and no reported immune escape site in S region. The strain will increase viral replication and infection for mutations A1762T and G1764A in the basal core promoter region, and mutations G1896A and G1899A in the pre-core region. The G1896A variant resulted in a premature stop codon and abolished HBeAg expression. HBsAg persisted for 26 weeks and HBeAg was still negative in CBA/CaJ mice. The present sequence is representative of the HBeAg-negative genome and may serve as a valuable reference for studying HBeAg-negative strains. The present findings were successfully verified in CBA/CaJ mice, demonstrating good applicability of the sequence.


Assuntos
DNA Viral/genética , Genoma Viral , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Animais , DNA Circular/genética , DNA Circular/imunologia , DNA Viral/imunologia , Modelos Animais de Doenças , Variação Genética , Genótipo , Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos CBA , Mutação , Regiões Promotoras Genéticas , Padrões de Referência , Análise de Sequência de DNA , Replicação Viral
8.
Chem Pharm Bull (Tokyo) ; 66(3): 319-326, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29311435

RESUMO

In order to make full use of artemisinin production waste and thus to reduce the production cost of artemisinin, we developed an efficient and scalable method to isolate high-purity dihydroartemisinic acid from artemisinin production waste by combining anion-exchange resin with silica-gel column chromatography. The adsorption and desorption characteristics of dihydroartemisinic acid on 10 types of anion-exchange resin were investigated, and the results showed that the 717 anion-exchange resin exhibited the highest capacity of adsorption and desorption to dihydroartemisinic acid. Adsorption isotherms were established for the 717 anion-exchange resin and they fitted well with both Langmuir and Freundlich model. Dynamic adsorption and desorption properties of 717 anion-exchange resin were characterized to optimize the chromatographic conditions. Subsequently, the silica-gel column chromatography was performed and dihydroartemisinic acid with a purity of up to 98% (w/w) was obtained. Finally, the scale-up experiments validated the preparative separation of high-purity dihydroartemisinic acid from industrial waste developed in the present work. This work presented for the first time an isolation of dihydroartemisinic acid with a purity of 98% from Artemisia annua (A. annua) by-product, which adds more value to this crop and has the potential to lower the prices of anti-malarial drugs.


Assuntos
Antimaláricos/química , Antimaláricos/isolamento & purificação , Artemisininas/química , Artemisininas/isolamento & purificação , Adsorção , Artemisia annua/química , Cromatografia Líquida , Cinética , Resíduos de Serviços de Saúde , Solventes
9.
Biomed Chromatogr ; 31(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27557482

RESUMO

Dihydroartemisinic acid (DHAA) is the direct precursor to artemisinin, an effective anti-malaria compound from Artemisia annua L. (A. annua), and it can be transformed to artemisinin without the catalysis of enzyme. A rapid and sensitive analysis of DHAA in A. annua is needed to screen excellent plant resources aimed to improve artemisinin production. In order to develop a rapid and sensitive determination method for DHAA in plant, the extraction and analysis conditions were extensively investigated in the present work. As a result, extraction of powdered A. annua leaves at 55°C for 50 min with chloroform resulted in the highest yield of DHAA, with a recovery of >98%. The precision of this gas chromatographic procedure ranged from 1.22 to 2.94% for intra-day and from 1.69 to 4.31% for inter-day, respectively. The accuracy was 99.55-103.02% for intra-day and 98.86-99.98% for inter-day, respectively. The measured LOQ and LOD values of the proposed method reached 5.00 and 2.00 µg/mL, respectively. Validation indicated the method was robust, quick, sensitive and adequate for DHAA analysis.


Assuntos
Artemisia annua/química , Artemisininas/análise , Cromatografia Gasosa/métodos , Ionização de Chama , Extratos Vegetais/análise
10.
Chem Pharm Bull (Tokyo) ; 65(8): 746-753, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28566563

RESUMO

Malaria is the most devastating parasitic disease worldwide. Artemisinin is the only drug that can cure malaria that is resistant to quinine-derived drugs. After the commercial extraction of artemisinin from Artemisia annua, the recovery of dihydroartemisinic acid (DHAA) from artemisinin extraction by-product has the potential to increase artemisinin commercial yield. Here we describe the development and optimization of an ultrasound-assisted alkaline procedure for the extraction of DHAA from artemisinin production waste using response surface methodology. Our results using this methodology established that NaOH at 0.36%, extraction time of 67.96 min, liquid-solid ratio of 5.89, and ultrasonic power of 83.9 W were the optimal conditions to extract DHAA from artemisinin production waste. Under these optimal conditions, we achieved a DHAA yield of 2.7%. Finally, we conducted a validation experiment, and the results confirmed the prediction generated by the regression model developed in this study. This work provides a novel way to increase the production of artemisinin per cultivated area and to reduce artemisinin production costs by recycling its commercial waste to obtain DHAA, an immediate precursor of artemisinin. The use of this technology may reduce the costs of artemisinin-based antimalarial medicines.


Assuntos
Artemisia annua/química , Artemisininas/isolamento & purificação , Ultrassom , Artemisininas/química , Concentração de Íons de Hidrogênio , Análise de Regressão , Hidróxido de Sódio/química , Propriedades de Superfície
11.
Plant Cell Physiol ; 56(8): 1624-40, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26092973

RESUMO

Canola is an important vegetable oil crop globally, and the understanding of the molecular mechanism underlying fatty acids biosynthesis during seed embryo development is an important research goal. Here we report the transcriptional profiling analysis of developing canola embryos using RNA-sequencing (RNA-Seq) method. RNA-Seq analysis generated 58,579,451 sequence reads aligned with 32,243 genes. It was found that a total of 55 differential expression genes (DEGs) encoding 28 enzymes function in carbon flow to fatty acids of storage TAG. Most of the DEGs encoding above enzymes showed similar expression pattern, indicating the DEGs are cooperatively involved in carbon flow into fatty acids. In addition, 41 DEGs associated with signal transductions, transport and metabolic processing of auxin, gibberellin, abscisic acid, cytokinin and salicylic acids were found in the RNA-Seq database, which indicates the important roles of the phytohormones in controlling embryo development and fatty acids synthesis. 122 DEGs encoding transcriptional factor family members were found in developing canola embryos. Furthermore, BnDOF5.6, a zinc finger transcriptional factor gene, found in RNA-Seq database was down-regulated in developing canola embryos. The transgenic plants displayed reduced embryo sizes, decreased fatty acids contents and altered seed fatty acids composition in canola. Down-regulated of BnDof5.6 also changed the expression levels of genes involved in fatty acids synthesis and desaturation. Our results indicate that BnDof5.6 is required for embryo development and fatty acids synthesis in canola. Overall this study presents new information on the global expression patterns of genes during embryo development and will expand our understanding of the complex molecular mechanism of carbon flow into fatty acids and embryo development in canola.


Assuntos
Brassica napus/genética , Ácidos Graxos/biossíntese , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Sementes/genética , Fatores de Transcrição/metabolismo , Ácido Abscísico/metabolismo , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Citocininas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Plantas Geneticamente Modificadas , Sementes/crescimento & desenvolvimento , Análise de Sequência de RNA , Fatores de Transcrição/genética , Dedos de Zinco
12.
Plant Cell Physiol ; 56(11): 2110-24, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26412778

RESUMO

The auxin response factor (ARF) genes encode a large family of proteins involved in auxin signaling transduction. SlARF3, a member of the ARF gene family, encodes a protein containing two conserved domains, B3 and ARF, and lacking an Aux/IAA domain. Expression analysis showed that SlARF3 has a particularly high expression level in trichomes. In situ hybridization also detected the SlARF3 transcripts in epidermal pavement cells of leaves. The physiological function of SlARF3 was studied by using the RNA interference (RNAi) strategy. SlARF3-down-regulated plants exhibited decreased density of epidermal pavement cells and obviously reduced density of type I, V and VI trichomes of leaves, which indicates the important role of SlARF3 in the formation of trichomes and epidermal cells in tomato. The number of shoot xylem cells was also decreased in SlARF3-down-regulated lines. Furthermore, RNA-sequencing (RNA-Seq) analysis identified 51 differentially expressed genes (DEGs) belonging to 14 transcription factor (TF) families, such as MYB, bHLH, WD40 and C2H2 zinc finger. Twenty-seven DEGs were involved in the metabolism and signaling transduction of phytohormones, such as auxin, ethylene and gibberellin. These results indicated the important roles of the TFs and hormones in auxin-dependent transcriptional regulation of trichome formation in tomato. Taken together, our results demonstrate that SlARF3 plays an important role in the formation of epidermal cells and trichomes and reveal novel and specific functions for ARFs in tomato developmental processes.


Assuntos
Proteínas de Plantas/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Tricomas/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/química , Transdução de Sinais , Fatores de Transcrição/química , Tricomas/citologia , Tricomas/crescimento & desenvolvimento , Xilema/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-26525851

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

14.
Microorganisms ; 12(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38930471

RESUMO

In this study, we focused on evaluating the impact of Pseudomonas abietaniphila BHJ04 on the growth of Pinus massoniana seedlings and its biocontrol efficacy against pine wilt disease (PWD). Additionally, the colonization dynamics of P. abietaniphila BHJ04 on P. massoniana were examined. The growth promotion experiment showed that P. abietaniphila BHJ04 significantly promoted the growth of the branches and roots of P. massoniana. Pot control experiments indicated that strain BHJ04 significantly inhibited the spread of PWD. There were significant changes in the expression of several genes related to pine wood nematode defense in P. massoniana, including chitinase, nicotinamide synthetase, and triangular tetrapeptide-like superfamily protein isoform 9. Furthermore, our results revealed significant upregulation of genes associated with the water stress response (dehydration-responsive proteins), genetic material replication (DNA/RNA polymerase superfamily proteins), cell wall hydrolase, and detoxification (cytochrome P450 and cytochrome P450 monooxygenase superfamily genes) in the self-regulation of P. massoniana. Colonization experiments demonstrated that strain BHJ04 can colonize the roots, shoots, and leaves of P. massoniana, and the colonization amount on the leaves was the greatest, reaching 160,000 on the 15th day. However, colonization of the stems lasted longer, with the highest level of colonization observed after 45 d. This study provides a preliminary exploration of the growth-promoting and disease-preventing mechanisms of P. abietaniphila BHJ04 and its ability to colonize pines, thus providing a new biocontrol microbial resource for the biological control of plant diseases.

15.
ACS Appl Mater Interfaces ; 16(22): 28333-28341, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38781511

RESUMO

The long-term objective in the field of heterogeneous catalysis is to develop an enzyme-like catalytic pathway that can achieve exceptional catalytic performance even at low temperatures. Herein, we have demonstrated a heterogeneous oxidase-type catalysis on the ZnO-supported Ru clusters (Ru/ZnO) for efficient H2 generation from an aqueous solution of formaldehyde (HCHO) at low temperatures. Due to its unique reaction pathway, the Ru/ZnO catalysts exhibited a temperature-insensitive activity for H2 generation at the temperature of 15 to 45 °C. Remarkably, even at a low temperature of 5 °C, the Ru/ZnO catalysts still enabled an H2 generation rate of 13.8 mmol gcat-1 h-1 with a turnover frequency (TOF) of 1678 h-1. Additionally, instead of producing a CO2/CO molecule, the HCHO molecule underwent a transformation into formic acid and/or formate as the byproduct. This finding presents a novel class of heterogeneous catalysts to expand the potential application scenarios of liquid hydrogen storage and transportation systems.

16.
Sci Bull (Beijing) ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38782658

RESUMO

Flexible pressure sensors with high sensitivity and linearity are highly desirable for robot sensing and human physiological signal detection. However, the current strategies for stabilizing axial microstructures (e.g., micro-pyramids) are mainly susceptible to structural stiffening during compression, thereby limiting the realization of high sensitivity and linearity. Here, we report a bending-induced non-equilibrium compression process that effectively enhances the compressibility of microstructures, thereby crucially improving the efficiency of interfacial area growth of electric double layer (EDL). Based on this principle, we fabricate an iontronic flexible pressure sensor with vertical graphene (VG) array electrodes. Ultra-high sensitivity (185.09 kPa-1) and linearity (R2 = 0.9999) are realized over a wide pressure range (0.49 Pa-66.67 kPa). It also exhibits remarkable mechanical stability during compression and bending. The sensor is successfully employed in a robotic gripping task to recognize the targets of different materials and shapes based on a multilayer perception (MLP) neural network. It opens the door to realizing haptic sensing capabilities for robotic hands and prosthetic limbs.

17.
J Cardiovasc Magn Reson ; 15: 32, 2013 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-23578191

RESUMO

BACKGROUND: This study proposed a fast and fully automatic calibration system to suppress the dark banding artifacts in balanced steady-state free precession (bSSFP) cardiovascular magnetic resonance (CMR) at 3.0 T. METHODS: Twenty-one healthy volunteers (18 men, 3 women; mean age 24.9 years) participated in this study after providing institutionally approved consent. The optimal frequency was obtained using sweep scans of transition-band low flip-angle bSSFP (bSSFP-L), performed with three conditions: breath-hold plus electrocardiography (ECG) triggering (BH + ECG), breath-hold only (BH), and free breathing (FB). A real-time feedback system was implemented to allow the performing of bSSFP-L calibration scanning and conventional cine bSSFP within one breath-hold. For each scan condition, the optimal phase was estimated using 20-point and 10-point spline fitting. RESULTS: Linear regression analysis indicated high correlation between the optimal phases obtained using BH and FB and those obtained using BH + ECG (R2 = 0.91 to 0.98, n = 21). The optimal phases obtained using 10-point datasets showed high correlation with the 20-point BH + ECG datasets (R2 = 0.92 to 0.99, n = 21); although the within-subject coefficient of variation (wsCV) was larger using 10-point fitting. The variation of repeated measurements was largest with FB acquisition and smallest with BH + ECG acquisition. The optimal frequency obtained by offline calculation and by real-time feedback calibration significantly reduced dark-band artifacts in cine bSSFP images (both p < .01). CONCLUSIONS: The proposed real-time feedback calibration method for bSSFP imaging is rapid and fully automatic. This method could greatly reduce dark-band artifacts in bSSFP images and facilitate clinical CMR at 3.0 T.


Assuntos
Coração/anatomia & histologia , Coração/fisiologia , Interpretação de Imagem Assistida por Computador/normas , Imagem Cinética por Ressonância Magnética/normas , Adulto , Artefatos , Automação/normas , Suspensão da Respiração , Calibragem , Técnicas de Imagem de Sincronização Cardíaca , Eletrocardiografia , Retroalimentação , Feminino , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Masculino , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
18.
Environ Sci Pollut Res Int ; 30(43): 97310-97318, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37587398

RESUMO

Cr (VI) is still of great concern due to its high toxicity, solubility, and mobility. The transformation of waste biomass to biochar is favorable for sustainable development. Hazelnut shell, an agriculture waste, was utilized as precursor to prepare biochar at 700 °C and firstly conducted for Cr (VI) removal. Nearly all 50 mg L-1 of Cr (VI) was removed from aqueous media in 180 min under the optimal conditions. The best compliance with pseudo-second-order kinetic model (R2 = 0.999) and Langmuir isotherm model (R2 = 0.999) indicated Cr (VI) removal was a monolayer chemisorption process. The hazelnut shell biochar exhibited superior performance on Cr (VI) removal at low pH (2.0) and Cr (VI) concentrations (≤ 50 mg L-1). Various techniques illustrated that the predominant mechanism of Cr (VI) removal by hazelnut shell biochar involved electrostatic attraction, reduction, and complexation. This study provides a promising low-cost alternative for Cr (VI) elimination from acidic wastewater and groundwater after extraction following by pH adjustment to 2.0.


Assuntos
Corylus , Água Subterrânea , Agricultura , Biomassa
19.
Sci Rep ; 13(1): 12823, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550374

RESUMO

Drought stress can severely affect sugarcane growth and yield. The objective of this research was to identify candidate genes in sugarcane tillering seedlings in response to drought stress. We performed a comparative phenotypic, physiological and transcriptomic analysis of tiller seedlings of drought-stressed and well-watered "Guire 2" sugarcane, in a time-course experiment (5 days, 9 days and 15 days). Physiological examination reviewed that SOD, proline, soluble sugars, and soluble proteins accumulated in large amounts in tiller seedlings under different intensities of drought stress, while MDA levels remained at a stable level, indicating that the accumulation of osmoregulatory substances and the enhancement of antioxidant enzyme activities helped to limit further damage caused by drought stress. RNA-seq and weighted gene co-expression network analysis (WGCNA) were performed to identify genes and modules associated with sugarcane tillering seedlings in response to drought stress. Drought stress induced huge down-regulated in gene expression profiles, most of down-regulated genes were mainly associated with photosynthesis, sugar metabolism and fatty acid synthesis. We obtained four gene co-expression modules significantly associated with the physiological changes under drought stress (three modules positively correlated, one module negatively correlated), and found that LSG1-2, ERF1-2, SHKA, TIL, HSP18.1, HSP24.1, HSP16.1 and HSFA6A may play essential regulatory roles as hub genes in increasing SOD, Pro, soluble sugar or soluble protein contents. In addition, one module was found mostly involved in tiller stem diameter, among which members of the BHLH148 were important nodes. These results provide new insights into the mechanisms by which sugarcane tillering seedlings respond to drought stress.


Assuntos
Saccharum , Transcriptoma , Plântula/genética , Saccharum/genética , Secas , Superóxido Dismutase/genética , Estresse Fisiológico/genética
20.
PhytoKeys ; 229: 61-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457387

RESUMO

A new species Rosafuningensis and its variant R.funingensisf.rosea, both collected from Yunnan Province, China, are, for the first time, documented and illustrated in this study. Morphological analysis in comparison with two related species in the wild, R.gigantea and R.rubus, presents distinguishable features through leaf surfaces, inflorescences and the shape of styles. R.funingensis leaf surfaces are abaxially villous, purple-red, pale green when mature, adaxially glabrous, dark green; inflorescences solitary or 2-5(7) in corymbose cyme; and styles connate into a column or not, exserted.

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