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1.
Mol Neurobiol ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422855

RESUMO

Depression is recognized globally as one of the most intractable diseases, and its complexity and diversity make treatment extremely challenging. Acupuncture has demonstrated beneficial effects in various psychiatric disorders. However, the underlying mechanisms of acupuncture's antidepressant action, particularly in depression, remain elusive. Therefore, this study aimed to investigate the effects of acupuncture on chronic unpredictability stress (CUMS)-induced depressive symptoms in rats and to further elucidate its underlying molecular mechanisms. All rats were exposed to CUMS of two stressors every day for 28 days, except for the control group. One hour before CUMS, rats were given a treatment with acupuncture, electroacupuncture, sham-acupuncture, or fluoxetine (2.1 mg/kg). Behavioral tests and biological detection methods were conducted in sequence to evaluate depression-like phenotype in rats. The findings of this study demonstrate that acupuncture therapy effectively ameliorated depression-like behavior induced by CUMS in rats. Additionally, acupuncture exerted a restorative effect on the alterations induced by CUMS in the levels of malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), brain-derived neurotrophic factor (BDNF), cyclic AMP response element-binding protein (CREB), postsynaptic density95 (PSD95), gamma-aminobutyric acid (GABA), and acetylcholine (ACh). Additionally, our findings indicate that acupuncture also modulates the ERK and Caspase-3 apoptotic pathways in the hippocampus of CUMS rats. This study suggests that acupuncture may play a potential preventive role by regulating hippocampal neuroinflammatory response, levels of oxidative stress, apoptotic processes, and enhancing synaptic plasticity.

2.
Food Chem ; 458: 140252, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38964113

RESUMO

Ethylene plays diverse roles in post-harvest processes of horticultural crops. However, its impact and regulation mechanism on the postharvest physiological deterioration (PPD) of cassava storage roots is unknown. In this study, a notable delay in PPD of cassava storage roots was observed when ethephon was utilized as an ethylene source. Physiological analyses and quantitative acetylproteomes were employed to investigate the regulation mechanism regulating cassava PPD under ethephon treatment. Ethephon was found to enhance the reactive oxygen species (ROS) scavenging system, resulting in a significant decrease in H2O2 and malondialdehyde (MDA) content. The comprehensive acetylome analysis identified 12,095 acetylation sites on 4403 proteins. Subsequent analysis demonstrated that ethephon can regulate the acetylation levels of antioxidant enzymes and members of the energy metabolism pathways. In summary, ethephon could enhance the antioxidant properties and regulate energy metabolism pathways, leading to the delayed PPD of cassava.


Assuntos
Manihot , Compostos Organofosforados , Proteínas de Plantas , Raízes de Plantas , Manihot/metabolismo , Manihot/química , Compostos Organofosforados/farmacologia , Compostos Organofosforados/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Etilenos/metabolismo , Etilenos/farmacologia , Acetilação , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Malondialdeído/metabolismo , Proteoma/metabolismo , Proteoma/efeitos dos fármacos , Proteoma/análise , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Peróxido de Hidrogênio/metabolismo
3.
Animal Model Exp Med ; 7(4): 408-418, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38807299

RESUMO

BACKGROUND: Myocardial infarction (MI) is an acute condition in which the heart muscle dies due to the lack of blood supply. Previous research has suggested that autophagy and angiogenesis play vital roles in the prevention of heart failure after MI, and miR-106a is considered to be an important regulatory factor in MI. But the specific mechanism remains unknown. In this study, using cultured venous endothelial cells and a rat model of MI, we aimed to identify the potential target genes of miR-106a and discover the mechanisms of inhibiting autophagy and angiogenesis. METHODS: We first explored the biological functions of miR-106a on autophagy and angiogenesis on endothelial cells. Then we identified ATG7, which was the downstream target gene of miR-106a. The expression of miR-106a and ATG7 was investigated in the rat model of MI. RESULTS: We found that miR-106a inhibits the proliferation, cell cycle, autophagy and angiogenesis, but promoted the apoptosis of vein endothelial cells. Moreover, ATG7 was identified as the target of miR-106a, and ATG7 rescued the inhibition of autophagy and angiogenesis by miR-106a. The expression of miR-106a in the rat model of MI was decreased but the expression of ATG7 was increased in the infarction areas. CONCLUSION: Our results indicate that miR-106a may inhibit autophagy and angiogenesis by targeting ATG7. This mechanism may be a potential therapeutic treatment for MI.


Assuntos
Proteína 7 Relacionada à Autofagia , Autofagia , MicroRNAs , Infarto do Miocárdio , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Ratos , Masculino , Neovascularização Fisiológica , Ratos Sprague-Dawley , Humanos , Células Endoteliais da Veia Umbilical Humana , Proliferação de Células , Células Endoteliais/metabolismo , Apoptose , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Modelos Animais de Doenças , Células Cultivadas , Angiogênese
4.
Ecotoxicol Environ Saf ; 277: 116358, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38653025

RESUMO

Exposure to nicotine by cigarette smoking have shown strongly defectives on the physiological function of ovaries, which in turn leads to disorders of fertility in women. However, the potential molecular mechanisms remain to be elucidated. In this study, we notably found that nicotine was likely to specifically raise the expression of histone deacetylase 3 (HDAC3) to promote the apoptosis and autophagy of granulosa cells (GCs) and block follicular maturation. Moreover, prostaglandin E2 (PGE2) inhibited the apoptosis of GCs and facilitated follicular maturation, and nicotine appeared to inhibit PGE2 secretion by freezing the expression of cyclooxygenase 1 (COX1), which was the rate-limiting and essential enzyme for PGE2 synthesis. Epigenetically, the nicotine was observed to diminish the histone H3 lysine 9 acetylation (H3K9ac) level and compact the chromatin accessibility in -1776/-1499 bp region of COX1 by evoking the expression of HDAC3, with the deactivated Cas9-HDAC3/sgRNA system. Mechanistically, the COX1 protein was found to pick up and degrade the autophagy related protein beclin 1 (BECN1) to control the autophagy of GCs. These results provided a potential new molecular therapy to recover the damage of female fertility induced by nicotine from cigarette smoking.


Assuntos
Autofagia , Dinoprostona , Células da Granulosa , Nicotina , Feminino , Autofagia/efeitos dos fármacos , Animais , Nicotina/toxicidade , Células da Granulosa/efeitos dos fármacos , Dinoprostona/metabolismo , Camundongos , Histona Desacetilases/metabolismo , Folículo Ovariano/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 1/genética
5.
BMC Anesthesiol ; 24(1): 58, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336613

RESUMO

BACKGROUND: Rectus sheath block (RSB) and transversus abdominis plane block (TAPB) have been shown to reduce opioid consumption and decrease postoperative pain scores in abdominal surgeries. However, there are no reports about the one-puncture technique of RSB combined with TAPB for perioperative pain management during laparoscopic upper abdominal surgery. METHODS: A total of 58 patients were randomly assigned to the control group (C), the TAP group (T), and the one-puncture technique of RSB combined with TAPB group (RT). The patients in group C did not receive any regional block. The patients in group T received ultrasound-guided subcostal TAPB with 30 mL of 0.33% ropivacaine on each side. The patients in the RT group received a combination of RSB and TAPB with 15 mL of 0.33% ropivacaine in each plane by one puncture technique. All patients received postoperative patient-controlled intravenous analgesia (PCIA) after surgeries. The range of blocks was recorded 20 min after the completion of the regional block. The postoperative opioid consumption, pain scores, and recovery data were recorded, including the incidence of emergence agitation (EA), the times of first exhaust and off-bed activity, the incidence of postoperative nausea and vomiting, dizziness. RESULTS: The range of the one-puncture technique in group RT covered all areas of surgical incisions. The visual analogue scale (VAS) score of the RT group is significantly lower at rest and during coughing compared to groups T and C at 4, 8, 12, and 24 h after surgery, respectively (P < 0.05). The consumption of sufentanil and the number of postoperative compressions of the analgesic pumps at 24 and 48 h in the RT group are significantly lower than those in groups T and C (P < 0.05). The incidence of EA in the RT group is significantly lower than that in groups T and C (P < 0.05). CONCLUSION: The one-puncture technique of RSB combined with TAPB provides effective postoperative analgesia for laparoscopic upper abdominal surgery, reduces the incidence of EA during PACU, and promotes early recovery. TRIAL REGISTRATION: ChiCTR, ChiCTR2300067271. Registered 3 Jan 2023, http://www.chictr.org.cn .


Assuntos
Benzamidinas , Laparoscopia , Manejo da Dor , Humanos , Ropivacaina , Manejo da Dor/efeitos adversos , Estudos Prospectivos , Analgésicos Opioides , Anestésicos Locais , Músculos Abdominais , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/etiologia , Laparoscopia/métodos , Analgesia Controlada pelo Paciente/métodos , Náusea e Vômito Pós-Operatórios , Punções
6.
Plant Physiol Biochem ; 206: 108291, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38141400

RESUMO

Abscisic acid (ABA) signaling plays a crucial role in plant development and response to abiotic/biotic stress. However, the function and regulation of protein phosphatase 2C (PP2C), a key component of abscisic acid signaling, under abiotic stress are still unknown in cassava, a drought-tolerant crop. In this study, a cassava PP2C gene (MePP2C24) was cloned and characterized. The MePP2C24 transcripts increased in response to mannitol, NaCl, and ABA. Overexpression of MePP2C24 in Arabidopsis resulted in increased sensitivity to drought stress and decreased sensitivity to exogenous ABA. This was demonstrated by transgenic lines having higher levels of malondialdehyde (MDA), ion leakage (IL), and reactive oxygen species (ROS), lower activities of catalase (CAT) and peroxidase (POD), and lower proline content than wild type (WT) under drought stress. Moreover, MePP2C24 overexpression caused decrease in expression of drought-responsive genes related to ABA signaling pathway. In addition, MePP2C24 was localized in the cell nucleus and showed self-activation. Furthermore, many MePYLs (MePYL1, MePYL4, MePYL7-9, and MePYL11-13) could interact with MePP2C24 in the presence of ABA, and MePYL1 interacted with MePP2C24 in both the presence and absence of ABA. Additionally, MebZIP11 interacted with the promoter of MePP2C24 and exerted a suppressive effect. Taken together, our results suggest that MePP2C24 acts as a negative regulator of drought tolerance and ABA response.


Assuntos
Arabidopsis , Manihot , Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Proteína Fosfatase 2C/genética , Proteína Fosfatase 2C/metabolismo , Manihot/metabolismo , Proteínas de Plantas/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Plantas Geneticamente Modificadas/metabolismo
7.
Genome Biol ; 24(1): 289, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38098107

RESUMO

BACKGROUND: Metabolites play critical roles in regulating nutritional qualities of plants, thereby influencing their consumption and human health. However, the genetic basis underlying the metabolite-based nutrient quality and domestication of root and tuber crops remain largely unknown. RESULTS: We report a comprehensive study combining metabolic and phenotypic genome-wide association studies to dissect the genetic basis of metabolites in the storage root (SR) of cassava. We quantify 2,980 metabolic features in 299 cultivated cassava accessions. We detect 18,218 significant marker-metabolite associations via metabolic genome-wide association mapping and identify 12 candidate genes responsible for the levels of metabolites that are of potential nutritional importance. Me3GT, MeMYB4, and UGT85K4/UGT85K5, which are involved in flavone, anthocyanin, and cyanogenic glucoside metabolism, respectively, are functionally validated through in vitro enzyme assays and in vivo gene silencing analyses. We identify a cluster of cyanogenic glucoside biosynthesis genes, among which CYP79D1, CYP71E7b, and UGT85K5 are highly co-expressed and their allelic combination contributes to low linamarin content. We find MeMYB4 is responsible for variations in cyanidin 3-O-glucoside and delphinidin 3-O-rutinoside contents, thus controlling SR endothelium color. We find human selection affects quercetin 3-O-glucoside content and SR weight per plant. The candidate gene MeFLS1 is subject to selection during cassava domestication, leading to decreased quercetin 3-O-glucoside content and thus increased SR weight per plant. CONCLUSIONS: These findings reveal the genetic basis of cassava SR metabolome variation, establish a linkage between metabolites and agronomic traits, and offer useful resources for genetically improving the nutrition of cassava and other root crops.


Assuntos
Estudo de Associação Genômica Ampla , Manihot , Humanos , Manihot/genética , Domesticação , Quercetina/metabolismo , Glucosídeos , Nutrientes
8.
Adv Mater ; 35(28): e2301442, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37022981

RESUMO

All-solid-state alkali ion batteries represent a future trend in battery technology, as well as provide an opportunity for low-cost metal fluoride electrode materials, if certain intrinsic problems can be resolved. In this work, a liquid metal activation strategy is proposed in which liquid Ga elements are generated in situ and doped into the LiF crystal structure by introducing a small amount of GaF3 . Benefiting from these two Ga states of existence, in which the liquid metal Ga can continuously maintain conformable ion/electron-transport networks, while doped Ga in the LiF crystal structure catalyzes LiF splitting, the lithium-ion storage capacity of MnF2 significantly increases by 87%. A similar effect can be obtained in FeF3 , where the sodium-ion storage capacity is enhanced by 33%. This universal strategy with few restrictions can be used to realize a complete renaissance of metal fluorides, as well as offer an opportunity for the new application of liquid metals in the field of energy storage.


Assuntos
Fluoretos , Gálio , Lítio , Fontes de Energia Elétrica , Eletrodos
9.
Adv Sci (Weinh) ; 10(6): e2205411, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36574468

RESUMO

Large-area polymer light-emitting diodes (PLEDs) manufactured by printing are required for flat-panel lighting and displays. Nevertheless, it remains challenging to fabricate large-area and stable deep-blue PLEDs with narrowband emission due to the difficulties in precisely tuning film uniformity and obtaining single-exciton emission. Herein, efficient and stable large-area deep-blue PLEDs with narrowband emission are prepared from encapsulated polydiarylfluorene. Encapsulated polydiarylfluorenes presented an efficient and stable deep-blue emission (peak: 439 nm; full width at half maximum (FWHM): 39 nm) in the solid state due to their single-chain emission behavior without inter-backbone chain aggregation. Large-area uniform blade-coated films (16 cm2 ) are also fabricated with excellent smoothness and morphology. Benefitting from efficient emission and excellent printed capacity, the blade-coated PLEDs with a device area of 9 mm2 realized uniform deep-blue emission (FWHM: 38 nm; CIE: 0.153, 0.067), with a corresponding maximum external quantum efficiency and the brightness comparable to those of devices based on spin-coated films. Finally, considering the essential role of deep-blue LEDs, a preliminary patterned PLED array with a pixel size of 800 × 1000 µm2 and a monochrome display is fabricated, highlighting potential full-color display applications.

10.
J Agric Food Chem ; 70(40): 12830-12840, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36183268

RESUMO

Phytohormone abscisic acid (ABA) influences the shelf life of fruit, vegetables, and tubers after harvest. However, little is known about the core signaling module involved in ABA's control of the postharvest physiological process. Exogenous ABA alleviated postharvest physiological deterioration (PPD) symptoms of sliced cassava tuberous roots, increased endogenous ABA levels, and reduced endogenous H2O2 content. The specific ABA signaling module during the PPD process was identified as MePYL6-MePP2C16-MeSnRK2.1-MebZIP5/34. MebZIP5/MebZIP34 directly binds to and activates the promoters of MeGRX6/MeMDAR1 through ABRE elements. Exogenous ABA significantly induced the expression of genes involved in this module, glutaredoxin content, and monodehydroascorbate reductase activity. We presented a hypothesis suggesting that MePYL6-MePP2C16-MeSnRK2.1-MebZIP5/34-MeGRX6/MeMDAR1 is involved in ABA-induced antioxidative capacity, thus alleviating PPD symptoms in cassava tuberous roots. The identification of the specific signaling module involved in ABA's control of PPD provides a basis and potential targets for extending the shelf life of cassava tuberous roots.


Assuntos
Ácido Abscísico , Manihot , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Glutarredoxinas/genética , Peróxido de Hidrogênio/metabolismo , Manihot/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/metabolismo
11.
Front Nutr ; 9: 842693, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35449540

RESUMO

Yellow roots are of higher nutritional quality and better appearance than white roots in cassava, a crucial tropical and subtropical root crop. In this work, two varieties with yellow and white cassava roots were selected to explore the mechanisms of color formation by using comparative metabolome and transcriptome analyses during seven developmental stages. Compared with the white-rooted cassava, anthocyanins, catechin derivatives, coumarin derivatives, and phenolic acids accumulated at higher levels in yellow-rooted cassava. Anthocyanins were particularly enriched and displayed different accumulation patterns during tuberous root development. This was confirmed by metabolic comparisons between five yellow-rooted and five white-rooted cassava accessions. The integrative metabolomic and transcriptomic analysis further revealed a coordinate regulation of 16 metabolites and 11 co-expression genes participating in anthocyanin biosynthesis, suggesting a vital role of anthocyanin biosynthesis in yellow pigmentation in cassava tuberous roots. In addition, two transcriptional factors, i.e., MeMYB5 and MeMYB42, were also identified to co-express with these anthocyanin biosynthesis genes. These findings expand our knowledge on the role of anthocyanin biosynthesis in cassava root color formation, and offer useful information for the genetic breeding of yellow-rooted cassava in the future.

12.
Genome Biol ; 22(1): 316, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34784936

RESUMO

BACKGROUND: Heterozygous genomes are widespread in outcrossing and clonally propagated crops. However, the variation in heterozygosity underlying key agronomic traits and crop domestication remains largely unknown. Cassava is a staple crop in Africa and other tropical regions and has a highly heterozygous genome. RESULTS: We describe a genomic variation map from 388 resequenced genomes of cassava cultivars and wild accessions. We identify 52 loci for 23 agronomic traits through a genome-wide association study. Eighteen allelic variations in heterozygosity for nine candidate genes are significantly associated with seven key agronomic traits. We detect 81 selective sweeps with decreasing heterozygosity and nucleotide diversity, harboring 548 genes, which are enriched in multiple biological processes including growth, development, hormone metabolisms and responses, and immune-related processes. Artificial selection for decreased heterozygosity has contributed to the domestication of the large starchy storage root of cassava. Selection for homozygous GG allele in MeTIR1 during domestication contributes to increased starch content. Selection of homozygous AA allele in MeAHL17 is associated with increased storage root weight and cassava bacterial blight (CBB) susceptibility. We have verified the positive roles of MeTIR1 in increasing starch content and MeAHL17 in resistance to CBB by transient overexpression and silencing analysis. The allelic combinations in MeTIR1 and MeAHL17 may result in high starch content and resistance to CBB. CONCLUSIONS: This study provides insights into allelic variation in heterozygosity associated with key agronomic traits and cassava domestication. It also offers valuable resources for the improvement of cassava and other highly heterozygous crops.


Assuntos
Domesticação , Variação Genética , Manihot/genética , Análise de Sequência de DNA , Mapeamento Cromossômico , Produtos Agrícolas/genética , Proteínas de Ligação a DNA/genética , Genoma de Planta , Estudo de Associação Genômica Ampla , Proteínas Nucleares/genética , Fenótipo , Filogenia , Proteínas de Plantas/genética
13.
Biochem Genet ; 59(6): 1599-1616, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34009493

RESUMO

Plant 14-3-3 proteins play key roles in regulating growth, development, and stress responses. However, little is known about this gene family in papaya (Carica papaya L.). We characterized eight 14-3-3 genes from the papaya genome and designed them as CpGRF1-8. Based on phylogenetic, conserved motif, and gene structure analyses, papaya CpGRFs were divided into ε and non-ε groups. Expression analysis showed differential and class-specific transcription patterns in different organs. Quantitative real-time polymerase chain reaction analysis showed that most CpGRFs had large changes in expression during fruit development and ripening. This indicated that the CpGRFs were involved in regulating fruit development and ripening. Significant expression changes occurred after cold, salt, and drought treatments in papaya seedlings, indicating that CpGRFs were also involved in signaling responses to abiotic stress. These results provide a transcription profile of 14-3-3 genes in organs, during fruit development and ripening and in response to stress. Some highly expressed, fruit-specific, and stress-responsive candidate CpGRFs will be identified for further genetic improvement of papayas.


Assuntos
Carica , Carica/genética , Carica/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
15.
Mol Biol Rep ; 48(2): 1127-1138, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33492573

RESUMO

The BAHD family is involved in different biological roles in plants, including secondary metabolite synthesis, improving abiotic/biotic stress resistance, and influencing fruit quality. However, the knowledge about BAHD in banana, an important fruit crop, is limited. In this study, 46 banana BAHD genes (MaBAHDs) were identified and divided into four groups according to phylogenetic analysis. Most of the MaBAHD genes in the same group presented similar conserved motifs and genetic structures. MaBAHD genes have similar expression patterns in two banana varieties, and more genes showed high expressions in the roots. The comprehensive MaBAHD gene expression patterns obtained from two varieties of banana showed valuable information regarding their participation in fruit development, ripening, and response to abiotic/biotic stresses, suggesting that they play key roles in these processes. The systematic analysis of MaBAHD genes offered basic insight for further gene functional assays and potential applications in genetically improving banana cultivars.


Assuntos
Musa/genética , Desenvolvimento Vegetal/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genoma de Planta/genética , Família Multigênica/genética , Musa/crescimento & desenvolvimento , Filogenia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
16.
Appl Opt ; 59(34): 10801-10807, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33361900

RESUMO

A real-time, nondestructive mid-infrared (mid-IR) platform was proposed for isotopic methane detection. The measurement system consisted of a tunable mid-IR laser, a miniaturized gas chamber, and a mid-IR signal receiver. The isotope ratio of the 12CH4/13CH4 was identified by measuring the mid-IR spectrum at λ=3.2-3.5µm.In-situ12CH4/13CH4 monitoring was then achieved by tracing the characteristic mid-IR absorption peaks assigned to the 12CH4 at λ=3.328µm and 13CH4 at λ=3.340µm. The real-time methane isotope analysis can be applied to environmental monitoring and petroleum industries.

17.
Opt Express ; 27(19): 26512-26522, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674531

RESUMO

Real-time gas mixture analysis has been demonstrated using various linear variable filter (LVF)-enabled mid-infrared (mid-IR) visualizations. Due to the characteristic absorptions of different gases, the algorithm-enabled sensing method has the ability to detect multi-component gas mixtures noninvasively. The proposed system consisted of a broadband light source, a gas mixing and delivery chamber made by polydimethylsiloxane (PDMS), a LVF, and a real-time monitoring mid-IR camera. The system performance was evaluated by detecting CH4 and C2H2 at their characteristic C-H absorptions from λ = 3.0 to 3.5 µm. A fast and accurate identification of gas samples was achieved. Therefore, our real-time and non-destructive gas analysis system enables a new visualization technology for environmental monitoring and industrial measurement.

18.
Polymers (Basel) ; 9(7)2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30970965

RESUMO

In this paper, we developed a photo-thermo staged-responsive shape-memory polymer network which has a unique ability of being spontaneously photo-responsive deformable and thermo-responsive shape recovery. This new type of shape-memory polyurethane network (A-SMPUs) was successfully synthesized with 4,4-azodibenzoic acid (Azoa), hexamethylenediisocyanate (HDI) and polycaprolactone (PCL), followed by chemical cross-linking with glycerol (Gl). The structures, morphology, and shape-memory properties of A-SMPUs have been carefully investigated. The results demonstrate that the A-SMPUs form micro-phase separation structures consisting of a semi-crystallized PCL soft phase and an Azoa amorphous hard phase that could influence the crystallinity of PCL soft phases. The chemical cross-linking provided a stable network and good thermal stability to the A-SMPUs. All A-SMPUs exhibited good triple-shape-memory properties with higher than 97% shape fixity ratio and 95% shape recovery ratio. Additionally, the A-SMPUs with higher Azoa content exhibited interesting photo-thermo two-staged responsiveness. A pre-processed film with orientated Azoa structure exhibited spontaneous curling deformation upon exposing to ultraviolet (UV) light, and curling deformation is constant even under Vis light. Finally, the curling deformation can spontaneously recover to the original shape by applying a thermal stimulus. This work demonstrates new synergistically multi-responsive SMPUs that will have many applications in smart science and technology.

19.
Plant Dis ; 101(12): 2073-2078, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30677384

RESUMO

Fusarium wilt of banana, which is caused by Fusarium oxysporum f. sp. cubense, is one of the most serious diseases of banana. F. oxysporum f. sp. cubense race 1 (Foc1) and race 4 (Foc4) are the most prevalent pathogens of banana cultivars in the world. To understand the differences in the infection processes between Foc1 and Foc4, green fluorescent protein-tagged strains of F. oxysporum f. sp. cubense tropical race 4 (FocTR4) and Foc1 were used to inoculate 'Brazil Cavendish' banana. At 2 days postinoculation (dpi), it was observed that the spores and hyphae of both Foc1 and Foc4 attached to the root hairs and root epidermis. At 3 dpi, the hyphae of both Foc1 and Foc4 were found in the vascular tissues of roots. However, Foc4 was observed in the parenchymal cells of banana root, whereas Foc1 was not found in parenchymal cells at 7 dpi. Furthermore, few Foc1 hyphae were observed in a few xylems whereas many more Foc4 hyphae were present in many xylems and phloems. Foc4 was observed in the vascular tissues of banana rhizomes, whereas no Foc1 was found in rhizomes 2 months after inoculation. The attachment process in F. oxysporum f. sp. cubense infection was further studied with scanning electron microscopy. Foc4 was observed to penetrate into banana roots from the intercellular space of the epidermis and wounds, whereas Foc1 mainly penetrated from the wounds but not from the intercellular space of the epidermis. Therefore, direct root penetration and rhizome vascular colonization by F. oxysporum f. sp. cubense are the key steps in the successful infection of Brazil Cavendish.


Assuntos
Fusarium , Musa , Raízes de Plantas , Rizoma , Fusarium/fisiologia , Musa/microbiologia , Raízes de Plantas/microbiologia , Rizoma/microbiologia
20.
J Neurol Sci ; 362: 263-5, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26944160

RESUMO

BACKGROUND: Previous studies to estimate burden of neurological disorders in Africa are limited to inpatients in urban hospitals. The spectrum of neurological conditions in rural Africa remains unclear. OBJECTIVE: To determine the spectrum of neurological presentations in an outpatient setting in rural Zimbabwe. METHODS: Clinical data was collected from outpatient records at Karanda Mission Hospital, a rural community hospital in Northern Zimbabwe from February 2013 to February 2014. Each patient visit was entered in an outpatient record book by a registered nurse or a nurse trainee. Demographic details such as age, sex, weight and address of the patient, and clinical details such as diagnosis on discharge and medications prescribed were recorded in the record book following assessment by a physician or nurse practitioner. Each visit corresponded to a separate entry in the study. RESULTS: We recorded a total of 19,206 visits in the outpatient registry. The average age was 46.41 years (standard deviation=21.46), and there were more visits from women (57.81%). 11.63% (2233) of all visits had a neurological diagnosis at discharge. The most common neurological diagnoses were epilepsy/seizures (24.38%), followed by neuropathies (13.63%), headaches (11.4%) and strokes (4.6%). CONCLUSIONS: One in ten cases in an outpatient setting in rural Zimbabwe were neurologically related. Further studies are required to determine the public health burden of neurological disorders in rural Africa. The development and funding of educational initiatives in resource-limited areas is needed to improve neurological diagnosis and care.


Assuntos
Epilepsia/etiologia , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/epidemiologia , Pacientes Ambulatoriais , Adulto , Idoso , Epilepsia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , População Rural , Zimbábue/epidemiologia
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