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1.
J Cell Mol Med ; 28(5): e18087, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38146607

RESUMEN

The role of NETosis and its related molecules remains unclear in gastric cancer. The data used in this study was directly downloaded from the Cancer Genome Atlas (TCGA) database. All analysis and plots are completed in R software using diverse R packages. In our study, we collected the list of NETosis-related genes from previous publications. Based on the list and expression profile of gastric cancer patients from the TCGA database, we identified the NETosis-related genes significantly correlated with patients survival. Then, CLEC6A, BST1 and TLR7 were identified through LASSO regression and multivariate Cox regression analysis for prognosis model construction. This prognosis model showed great predictive efficiency in both training and validation cohorts. We noticed that the high-risk patients might have a worse survival performance. Next, we explored the biological enrichment difference between high- and low-risk patients and found that many carcinogenic pathways were upregulated in the high-risk patients. Meanwhile, we investigated the genomic instability, mutation burden and immune microenvironment difference between high- and low-risk patients. Moreover, we noticed that low-risk patients were more sensitive to immunotherapy (85.95% vs. 56.22%). High-risk patients were more sensitive to some small molecules compounds like camptothecin_1003, cisplatin_1005, cytarabine_1006, nutlin-3a (-)_1047, gemcitabine_1190, WZ4003_1614, selumetinib_1736 and mitoxantrone_1810. In summary, our study comprehensively explored the role of NETosis-related genes in gastric cancer, which can provide direction for relevant studies.


Asunto(s)
Biomarcadores de Tumor , Regulación Neoplásica de la Expresión Génica , Inmunoterapia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Neoplasias Gástricas/inmunología , Pronóstico , Inmunoterapia/métodos , Biomarcadores de Tumor/genética , Receptor Toll-Like 7/genética , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Proteínas Ligadas a GPI/genética , Masculino , Transcriptoma/genética , Femenino , Perfilación de la Expresión Génica , Bases de Datos Genéticas , Persona de Mediana Edad
2.
Antonie Van Leeuwenhoek ; 116(12): 1305-1316, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37773470

RESUMEN

Human infections by environmental bacteria is becoming an increasing problem and has become a matter of great concern due to the adverse effects worldwide. In this study, we reported a new environmental pathogen. Isolate GX5518T was a novel Gram-negative, aerobic, non-motile, pleomorphic and red-pigmented bacterium, was isolated from human wound secretions (GuangXi, People's Republic of China). Growth occurred at pH 6.0-8.0 (optimum, pH 7.0) and 10-37 °C (optimum, 28-32 °C) with 0-1.5% (w/v) NaCl in R2A agar. Comparative analysis of the 16S rRNA gene sequences revealed that isolate GX5518T was closely related to Fluviispira sanaruensis JCM 31447T (99.73%) and Fluviispira multicolorata 33A1-SZDPT (98.49%). However, the estimated ANI values of the isolate GX5518T compared to the F. sanaruensis JCM 31447T and F. multicolorata 33A1-SZDPT were 88.67% and 77.35%, respectively. The estimated dDDH, ANI and AAI values between isolate GX5518T and its closely related strains were below the threshold values generally considered for recognizing a new species. The genome size was 3.6 Mbp and the DNA G + C content was 33.1%. The predominant fatty acids (> 5%) in GX5518T cells were iso-C15:0, C16:0, C17:0, C17:1 ω8c and C16:1 ω7c/C16:1 ω6c. The major menaquinone was MK-8 (86.9%). The polar lipids were phosphatidylethanolamine (PE), phosphatidylglycerol (PG) and three unknown lipids (L1-3). The chemical composition was different from that of the F. sanaruensis JCM 31447T. Comparative genomics analysis between isolate GX5518T and its related strains revealed that there were a number of genes involved in resistance to antibiotics and toxic compounds in isolate GX5518T, which were responsible for the copper homeostasis, cobalt-zinc-cadmium resistance, resistance to fluoroquinolones, and zinc resistance. Based on the phenotypic, chemotaxonomic, and genomic analyses, isolate GX5518T (= CGMCC 1.18685T = KCTC 82149T) represents a novel species of the genus Fluviispira, for which the name Fluviispira vulneris sp. nov. is proposed.


Asunto(s)
Ácidos Grasos , Fosfolípidos , Humanos , Fosfolípidos/química , ARN Ribosómico 16S/genética , Hibridación de Ácido Nucleico , ADN Bacteriano/genética , Análisis de Secuencia de ADN , China , Ácidos Grasos/química , Proteobacteria/genética , Zinc , Filogenia , Técnicas de Tipificación Bacteriana
3.
Molecules ; 28(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37049949

RESUMEN

The effective removal of oxytetracycline hydrochloride (OTC) from the water environment is of great importance. Adsorption as a simple, stable, and cost-effective technology is regarded as an important method for removing OTC. Herein, a low-cost biochar with a developed mesoporous structure was synthesized via pyrolysis of poplar leaf with potassium bicarbonate (KHCO3) as the activator. KHCO3 can endow biochar with abundant mesopores, but excessive KHCO3 cannot continuously promote the formation of mesoporous structures. In comparison with all of the prepared biochars, PKC-4 (biochar with a poplar leaf to KHCO3 mass ratio of 5:4) shows the highest adsorption performance for OTC as it has the largest surface area and richest mesoporous structure. The pseudo-second-order kinetic model and the Freundlich equilibrium model are more consistent with the experimental data, which implies that the adsorption process is multi-mechanism and multi-layered. In addition, the maximum adsorption capacities of biochar are slightly affected by pH changes, different metal ions, and different water matrices. Moreover, the biochar can be regenerated by pyrolysis, and its adsorption capacity only decreases by approximately 6% after four cycles. The adsorption of biochar for OTC is mainly controlled by pore filling, though electrostatic interactions, hydrogen bonding, and π-π interaction are also involved. This study realizes biomass waste recycling and highlights the potential of poplar leaf-based biochar for the adsorption of antibiotics.


Asunto(s)
Oxitetraciclina , Contaminantes Químicos del Agua , Oxitetraciclina/química , Adsorción , Contaminantes Químicos del Agua/química , Carbón Orgánico/química , Cinética , Agua
4.
Sensors (Basel) ; 18(4)2018 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-29642508

RESUMEN

Interrupted sampling repeater jamming (ISRJ) is an effective way of deceiving coherent radar sensors, especially for linear frequency modulated (LFM) radar. In this paper, for a simplified scenario with a single jammer, we propose a dynamic electronic counter-counter measure (ECCM) scheme based on jammer parameter estimation and transmitted signal design. Firstly, the LFM waveform is transmitted to estimate the main jamming parameters by investigating the discontinuousness of the ISRJ's time-frequency (TF) characteristics. Then, a parameter-adjusted intra-pulse frequency coded signal, whose ISRJ signal after matched filtering only forms a single false target, is designed adaptively according to the estimated parameters, i.e., sampling interval, sampling duration and repeater times. Ultimately, for typical jamming scenes with different jamming signal ratio (JSR) and duty cycle, we propose two particular ISRJ suppression approaches. Simulation results validate the effective performance of the proposed scheme for countering the ISRJ, and the trade-off relationship between the two approaches is demonstrated.

5.
Sensors (Basel) ; 18(4)2018 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-29670028

RESUMEN

This paper focuses on developing an anti-velocity jamming strategy that enhances the ability of a pulse-Doppler (PD) radar to detect moving targets in the presence of translational and/or micro motion velocity jamming generated by the digital radio frequency memory (DRFM) repeat jammers. The strategy adopts random pulse initial phase (RPIP) pulses as its transmitted signal and thus gets DRFM jammers not adaptable to the randomness of initial phase of the transmitted pulses in the pulse repetition interval (PRI) domain. The difference between the true target echo and the false target jamming signal at each PRI is then utilized to recognize the true and false target signals. In particular, an entropy based multi-channel processing scheme is designed to extract the information of the received signal without the assumption that true and false targets must be both included within one coherent processing interval (CPI). Information such as the component of the received signal (target echo only, jamming only or both) or the operating manner of DRFM repeat jammer can be gained (if jamming exists). Meanwhile, we solve the false target recognition problem under sparse theory frame and our previous work named the short-time sparse recovery (STSR) algorithm is introduced to recover the motion parameters of the true and/or false targets in the time-frequency domain. It should be pointed out that both the translational false target jamming and micro motion target jamming can be recognized in our strategy. The performance of the proposed strategy is compared with the correlated processing (CP) method used by most extant strategies. It is shown that the proposed strategy can successfully recognize the existence of true and/or false targets and keep its power in recovering corresponding motion parameters even when the jamming environment is strong.

6.
J Korean Med Sci ; 31(6): 836-42, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27247490

RESUMEN

To investigate the function and regulation mechanism of ATP-binding cassette, subfamily G, member 2 (ABCG2) in retinoblastoma cancer stem cells (RCSCs), a long-term culture of RCSCs from WERI-Rb1 cell line was successfully established based on the high expression level of ABCG2 on the surface of RCSCs. To further explore the molecular mechanism of ABCG2 on RCSCs, a microRNA that specifically targets ABCG2 was predicted. Subsequently, miR-3163 was selected and confirmed as the ABCG2-regulating microRNA. Overexpression of miR-3163 led to a significant decrease in ABCG2 expression. Additionally, ABCG2 loss-of-function induced anti-proliferation and apoptosis-promoting functions in RCSCs, and multidrug resistance to cisplatin, carboplatin, vincristine, doxorubicin, and etoposide was greatly improved in these cells. Our data suggest that miR-3163 has a significant impact on ABCG2 expression and can influence proliferation, apoptosis, and drug resistance in RCSCs. This work may provide new therapeutic targets for retinoblastoma.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , MicroARNs/metabolismo , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Regiones no Traducidas 3' , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/antagonistas & inhibidores , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Antagomirs/metabolismo , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Secuencia de Bases , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Silenciador del Gen , Humanos , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Retinoblastoma/metabolismo , Retinoblastoma/patología , Alineación de Secuencia , Transfección
7.
Bioprocess Biosyst Eng ; 39(1): 37-44, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26531749

RESUMEN

Ganoderma, as a Chinese traditional medicine, has multiple bioactivities. However, industrial production was limited due to low yield during Ganoderma fermentation. In this work, sucrose was found to greatly enhance intracellular polysaccharide (IPS) content and specific extracellular polysaccharide (EPS) production rate. The mechanism was studied by analyzing the activities of enzymes related to polysaccharide biosynthesis. The results revealed that sucrose regulated the activities of phosphoglucomutase and phosphoglucose isomerase. When glucose and sucrose mixture was used as carbon source, biomass, polysaccharide and ganoderic acids (GAs) production was greatly enhanced. A sucrose fed-batch strategy was developed in 10-L bioreactor, and was scaled up to 300-L bioreactor. The biomass, EPS and IPS production was 25.5, 2.9 and 4.8 g/L, respectively, which was the highest biomass and IPS production in pilot scale. This study provides information for further understanding the regulation mechanism of Ganoderma polysaccharide biosynthesis. It demonstrates that sucrose fed-batch is a useful strategy for enhancing Ganoderma biomass, polysaccharide and GAs production.


Asunto(s)
Biomasa , Reactores Biológicos , Polisacáridos Fúngicos/biosíntesis , Reishi/crecimiento & desarrollo , Triterpenos/metabolismo
8.
Bioprocess Biosyst Eng ; 37(9): 1789-97, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24577738

RESUMEN

Polysaccharides and ganoderic acids (GAs) are the major bioactive constituents of Ganoderma species. However, the commercialization of their production was limited by low yield in the submerged culture of Ganoderma despite improvement made in recent years. In this work, twelve Ganoderma strains were screened to efficiently produce polysaccharides and GAs, and Ganoderma lucidum 5.26 (GL 5.26) that had been never reported in fermentation process was found to be most efficient among the tested stains. Then, the fermentation medium was optimized for GL 5.26 by statistical method. Firstly, glucose and yeast extract were found to be the optimum carbon source and nitrogen source according to the single-factor tests. Ferric sulfate was found to have significant effect on GL 5.26 biomass production according to the results of Plackett-Burman design. The concentrations of glucose, yeast extract and ferric sulfate were further optimized by response surface methodology. The optimum medium composition was 55 g/L of glucose, 14 g/L of yeast extract, 0.3 g/L of ferric acid, with other medium components unchanged. The optimized medium was testified in the 10-L bioreactor, and the production of biomass, IPS, total GAs and GA-T enhanced by 85, 27, 49 and 93 %, respectively, compared to the initial medium. The fermentation process was scaled up to 300-L bioreactor; it showed good IPS (3.6 g/L) and GAs (670 mg/L) production. The biomass was 23.9 g/L in 300-L bioreactor, which was the highest biomass production in pilot scale. According to this study, the strain GL 5.26 showed good fermentation property by optimizing the medium. It might be a candidate industrial strain by further process optimization and scale-up study.


Asunto(s)
Fermentación , Ganoderma/metabolismo , Polisacáridos/metabolismo , Triterpenos/metabolismo , Reactores Biológicos , Medios de Cultivo , Modelos Teóricos
9.
Adv Sci (Weinh) ; 11(13): e2304834, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38269856

RESUMEN

Architected materials design across orders of magnitude length scale intrigues exceptional mechanical responses nonexistent in their natural bulk state. However, the so-termed mechanical metamaterials, when scaling bottom down to the atomistic or microparticle level, remain largely unexplored and conventionally fall out of their coarse-resolution, ordered-pattern design space. Here, combining high-throughput molecular dynamics (MD) simulations and machine learning (ML) strategies, some intriguing atomistic families of disordered mechanical metamaterials are discovered, as fabricated by melt quenching and exemplified herein by lightweight-yet-stiff cellular materials featuring a theoretical limit of linear stiffness-density scaling, whose structural disorder-rather than order-is key to reduce the scaling exponent and is simply controlled by the bonding interactions and their directionality that enable flexible tunability experimentally. Importantly, a systematic navigation in the forcefield landscape reveals that, in-between directional and non-directional bonding such as covalent and ionic bonds, modest bond directionality is most likely to promotes disordered packing of polyhedral, stretching-dominated structures responsible for the formation of metamaterials. This work pioneers a bottom-down atomistic scheme to design mechanical metamaterials formatted disorderly, unlocking a largely untapped field in leveraging structural disorder in devising metamaterials atomistically and, potentially, generic to conventional upscaled designs.

10.
Plants (Basel) ; 13(17)2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39273857

RESUMEN

Atmospheric elevated CO2 concentration (e[CO2]) decreases plant nitrogen (N) concentration while increasing water use efficiency (WUE), fertigation increases crop nutrition and WUE in crop; yet the interactive effects of e[CO2] coupled with two N-fertigation levels during deficit irrigation on plant gas exchange, root morphology and WUE remain largely elusive. The objective of this study was to explore the physiological and growth responses of ambient [CO2] (a[CO2], 400 ppm) and e[CO2] (800 ppm) tomato plant exposed to two N-fertigation regimes: (1) full irrigation during N-fertigation (FIN); (2) deficit irrigation during N-fertigation (DIN) under two N fertilizer levels (reduced N (N1, 0.5 g pot-1) and adequate N (N2, 1.0 g pot-1). The results indicated that e[CO2] associated with DIN regime induced the lower N2 plant water use (7.28 L plant-1), maintained leaf water potential (-5.07 MPa) and hydraulic conductivity (0.49 mol m-2 s-1 MPa-1), greater tomato growth in terms of leaf area (7152.75 cm2), specific leaf area (223.61 cm2 g-1), stem and total dry matter (19.54 g and 55.48 g). Specific root length and specific root surface area were increased under N1 fertilization, and root tissue density was promoted in both e[CO2] and DIN environments. Moreover, a smaller and denser leaf stomata (4.96 µm2 and 5.37 mm-2) of N1 plant was obtained at e[CO2] integrated with DIN strategy. Meanwhile, this combination would simultaneously reduce stomatal conductance (0.13 mol m-2 s-1) and transpiration rate (1.91 mmol m-2 s-1), enhance leaf ABA concentration (133.05 ng g-1 FW), contributing to an improvement in WUE from stomatal to whole-plant scale under each N level, especially for applying N1 fertilization (125.95 µmol mol-1, 8.41 µmol mmol-1 and 7.15 g L-1). These findings provide valuable information to optimize water and nitrogen fertilizer management and improve plant water use efficiency, responding to the potential resource-limited and CO2-enriched scenario.

11.
Sci Rep ; 13(1): 20614, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996624

RESUMEN

With the increasing complexity of the shortwave communication environment, the efficiency and accuracy of the manual detection of Morse code no longer meet actual needs. Therefore, this paper proposes a Morse code detection algorithm called YFDM. For the time-frequency image of the received signal, a combination module of deformable convolution and C3 is used to enhance the backbone network's attention to the abstract semantics and location information of Morse code. GSConv and VOV-GSCSP modules are used to build a lightweight neck network. Finally, the confidence propagation cluster (CP-Cluster) algorithm is used to filter the detection frame. In an ablation experiment, the parameters and giga floating-point operations per second (GFLOPs) of YFDM were 5.961 M and 9.74 G, respectively, 15.11% and 38.9% less than those of YOLOv5. Moreover, when WIoUv1 was used as the loss function of the bounding box, the AP0.5:0.95 and frames per second (FPS) values of the algorithm reached the highest values, 0.68 and 72.4. The experimental results indicate that the algorithm can effectively reduce the weight of the model while ensuring the detection accuracy and inference speed.

12.
Sci Total Environ ; 904: 166978, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37704141

RESUMEN

An adsorption experiment and a pot experiment were executed in order to explore the mechanisms by which biochar amendment in combination with reduced irrigation affects sodium and potassium uptake, root morphology, water use efficiency, and salinity tolerance of cotton plants. In the adsorption experiment, ten NaCl concentration gradients (0, 50, 100, 150, 200, 250, 300, 350, 400, and 500 mM) were set for testing isotherm adsorption of Na+ by biochar. It was found that the isotherms of Na+ adsorption by wheat straw biochar (WSP) and softwood biochar (SWP) were in accordance with the Langmuir isotherm model, and the Na+ adsorption ability of WSP (55.20 mg g-1) was superior to that of SWP (47.38 mg g-1). The pot experiment consisted three factors, viz., three biochar amendments (no biochar, WSP, and SWP), three irrigation strategies (deficit irrigation, partial root-zone drying irrigation - PRD, full irrigation), and two NaCl concentrations gradients (0 mM and 200 mM). The findings indicated that salinity stress lowered K+ concentration, root length, root surface area, and root volume (RV), but increased Na+ concentration, root average diameter, and root tissue density. However, biochar amendment decreased Na+ concentration, increased K+ concentration, and improved root morphology. In particular, the combination of WSP and PRD increased K+/Na+ ratio, RV, root weight density, root surface area density, water use efficiency, and partial factor productivity under salt stress, which can be a promising strategy to cope with drought and salinity stress in cotton production.


Asunto(s)
Gossypium , Agua , Cloruro de Sodio , Sodio , Iones , Tolerancia a la Sal
13.
Front Plant Sci ; 14: 1122742, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36743482

RESUMEN

Introduction: Biochar amendment provides multiple benefits in enhancing crop productivity and soil nutrient availability. However, whether biochar addition affects root morphology and alters plant nutrient uptake and shoot growth under different irrigation regimes remain largely unknown. Methods: A split-root pot experiment with maize (Zea mays L.) was conducted on clay loam soil mixed with 2% (w/w) of wheat-straw (WSP) and softwood (SWP) biochar. The plants were subjected to full (FI), deficit (DI), and alternate partial root-zone drying (PRD) irrigation from the fourth leaf to the grain-filling stage. Results and discussion: The results showed that, compared to plants grown in unamended soils, plants grown in the biochar-amended soils possessed greater total root length, area, diameter, volume, tips, forks, crossings, and root length density, which were further amplified by PRD. Despite a negative effect on soil available phosphorus (P) pool, WSP addition improved soil available nitrogen (N), potassium (K), and calcium (Ca) pool and cation exchange capacity under reduced irrigation. Even though biochar negatively affected nutrient concentrations in shoots as exemplified by lowered N, P, K (except leaf), and Ca concentration, it dramatically enhanced plant total N, P, K, Ca uptake, and biomass. Principal component analysis (PCA) revealed that the modified root morphology and increased soil available nutrient pools, and consequently, the higher plant total nutrient uptake might have facilitated the enhanced shoot growth and yield of maize plants in biochar-added soils. Biochar amendment further lowered specific leaf area but increased leaf N concentration per area-to-root N concentration per length ratio. All these effects were evident upon WSP amendment. Moreover, PRD outperformed DI in increasing root area-to-leaf area ratio. Overall, these findings suggest that WSP combined with PRD could be a promising strategy to improve the growth and nutrient uptake of maize plants.

14.
Plants (Basel) ; 12(3)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36771756

RESUMEN

The effects of inoculating plant growth promoting rhizobacteria (PGPR) and soil water deficits on crop growth and physiology remain largely unknown. Here, the responses of leaf gas exchange, growth, and water use efficiency (WUE) of tomato plants to Bacillus pumilus (B.p.) inoculation under four irrigation strategies (I1-I4) were investigated in a greenhouse. Results showed that soil water deficits, especially at I4 (20%, v/v), significantly decreased leaf stomatal conductance (gs), transpiration rate (Tr), and photosynthetic rate (An), and the decrease of gs and Tr were more pronounced than An. Reduced irrigation regimes significantly lowered dry matter and plant water use both in the non-B.p. control and the B.p. plants, while reduced irrigation significantly increased plant WUE, and B.p. inoculation had little effect on this parameter. Synergistic effects of PGPR and deficit irrigation on leaf gas exchange, leaf abscisic acid content, and stomatal density were found in this study, and specifically, B.p. treated plants at I4 possessed the highest WUE at stomatal and leaf scales, suggesting that B.p. inoculation could optimize water use and partly alleviate the negative effects of soil water deficit. These findings provide useful information for effective irrigation management and the application of PGPR in agriculture in the future.

15.
Artículo en Inglés | MEDLINE | ID: mdl-36913956

RESUMEN

Broad-bandgap semiconductor-based solar-blind ultraviolet (SBUV) photodetectors have attracted considerable research interest because of their broad applications in missile plume tracking, flame detectors, environmental monitoring, and optical communications due to their solar-blind nature and high sensitivity with low background radiation. Owing to its high light absorption coefficient, abundance, and wide tunable bandgap of 2-2.6 eV, tin disulfide (SnS2) has emerged as one of the most promising compounds for application in UV-visible optoelectronic devices. However, SnS2 UV detectors have some undesirable properties such as slow response speed, high current noise level, and low specific detectivity. This study reports a metal mirror-enhanced Ta0.01W0.99Se2/SnS2 (TWS) van der Waals heterodiode-based SBUV photodetector with an ultrahigh photoresponsivity (R) of ∼1.85 × 104 AW-1 and a fast speed with rising time (τr) of 3.3 µs and decay time (τd) of 3.4 µs. Notably, the TWS heterodiode device exhibits a significantly low noise equivalent power of ∼1.02 × 10-18 W Hz-1/2 and a high specific detectivity of ∼3.65 × 1014 cm Hz1/2 W-1. This study provides an alternative method for designing fast-speed SBUV photodetectors with enormous potential in applications.

16.
Bioprocess Biosyst Eng ; 35(7): 1201-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22382443

RESUMEN

Validamycin A (VAL-A) is an important and widely used agricultural antibiotic. In this study, statistical screening designs were applied to identify significant medium variables for VAL-A production and to find their optimal levels. The optimized medium caused 70% enhancement of VAL-A production. The difference between optimized medium and original medium suggested that low nitrogen source level might attribute to the enhancement of VAL-A production. The addition of different nitrogen sources to the optimized medium inhibited VAL-A production, which confirmed the importance of nitrogen concentration for VAL-A production. Furthermore, differences in structural gene transcription and enzyme activity between the two media were assayed. The results showed that lower nitrogen level in the optimized medium could regulate VAL-A production in gene transcriptional level. Our previous study indicated that the transcription of VAL-A structural genes could be enhanced at elevated temperature. In this work, the increased fermentation temperature from 37 to 42 °C with the optimized medium enhanced VAL-A production by 39%, which testified to the importance of structural gene transcription in VAL-A production. The information is useful for further VAL-A production enhancement.


Asunto(s)
Fermentación , Inositol/análogos & derivados , Nitrógeno/análisis , Streptomyces/metabolismo , Transcripción Genética , Secuencia de Bases , Medios de Cultivo , Cartilla de ADN , Glucosafosfato Deshidrogenasa/metabolismo , Inositol/biosíntesis , Reacción en Cadena en Tiempo Real de la Polimerasa , Streptomyces/genética
17.
Bioprocess Biosyst Eng ; 35(8): 1309-16, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22481376

RESUMEN

In order to enhance the production of validamycin A (VAL-A), a widely used agricultural antibiotic, a temperature shift strategy was developed in the fermentation of Streptomyces hygroscopicus 5008. VAL-A production and the transcriptional levels of its structural genes were enhanced in the optimal temperature shift condition. The addition of diphenyleneiodonium [DPI, reactive oxygen species (ROS) inhibitor] inhibited intracellular ROS level and VAL-A production, which indicated that ROS signal might contribute to the enhancement of VAL-A production in the temperature shift process. The transcriptional levels of stress response sigma factors SigmaB and SigmaH as well as global regulator PhoRP were enhanced, which suggested that these regulators might participate in the signal pathway. This study developed a useful strategy for VAL-A production. It will help to further understand the regulation mechanism of ROS on VAL-A synthesis. The involvement of ROS in this process will encourage researchers to develop new ROS induction strategies to enhance VAL-A production.


Asunto(s)
Especies Reactivas de Oxígeno/metabolismo , Streptomyces/crecimiento & desarrollo , Streptomyces/metabolismo , Calor , Inositol/análogos & derivados , Inositol/biosíntesis , Transcripción Genética/fisiología
18.
Sci Total Environ ; 806(Pt 1): 150513, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34571228

RESUMEN

Biochar has been advocated as a sustainable and eco-friendly practice to improve soil fertility and crop productivity which could aid in the mitigation of climate change. Nonetheless, the combined effects of biochar and irrigation on tobacco growth and soil nutrients in diverse soil types have been incompletely explored. We applied a split-root experiment to investigate the impacts of amendment with 2% softwood- (WBC) and wheat-straw biochar (SBC) on growth responses and rhizosphere soil nutrients availability of tobacco plants grown in a Ferralsol and an Anthrosol. All plants within same soil type received same amount of water daily by either conventional deficit irrigation (CDI) or alternate wetting-drying cycles irrigation (AWD). Compared to the un-amended controls, SBC addition enhanced biomass, carbon (C)-, phosphorus (P)- and potassium (K)-pool in the aboveground organs especially in Anthrosol, despite a negative effect on aboveground nitrogen (N)-pool. Regardless of soil type, biochar combined with AWD lowered root diameter while increased root tissue mass density to engage the plant in an acquisitive strategy for resources, therefore altered leaves stoichiometry as exemplified by lowered N/K, C/P and N/P and increased C/N. The addition of SBC induced a liming effect by increasing Anthrosol soil pH which was further amplified by AWD, but was unaffected on Ferralsol. Moreover, compared to the controls, SBC and AWD increased available P and K, and total C, total N and C/N ratio in the rhizosphere soil which coincided with the lowered soil C and N isotope composition (δ13C and δ15N), though a slight reduction in C and N stocks under AWD. However, such effects were not evident with WBC might be associated with its natures. Thus, combined SBC/AWD application might be an effective strategy to synergistically overcome nutrients restriction and improve tobacco productivity by intensifying nutrients cycling and optimizing plant growth strategies.


Asunto(s)
Rizosfera , Suelo , Carbón Orgánico , Nutrientes , Nicotiana
19.
Plants (Basel) ; 11(9)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35567127

RESUMEN

Drought stress often occurs concurrently with heat stress, yet the interacting effect of high vapor pressure deficit (VPD) and soil drying on the physiology of potato plants remains poorly understood. This study aimed to investigate the physiological and growth responses of potatoes to progressive soil drying under varied VPDs. Potato plants were grown either in four separate climate-controlled greenhouse cells with different VPD levels (viz., 0.70, 1.06, 1.40, and 2.12 kPa, respectively) or under a rainout shelter in the field. The VPD of each greenhouse cell was caused by two air temperature levels (23 and 30 °C) combined with two relative humidity levels (50 and 70%), and the VPD of the field was natural conditions. Irrigation treatments were commenced three or four weeks after planting in greenhouse cells or fields, respectively. The results indicated that soil water deficits limited leaf gas exchange and shoot dry matter (DMshoot) of plants while increasing the concentration of abscisic acid (ABA) in the leaf and xylem, as well as water use efficiency (WUE) across all VPD levels. High VPD decreased stomatal conductance (gs) but increased transpiration rate (Tr). High VPD increased the threshold of soil water for Tr began to decrease, while the soil water threshold for gs depended on temperature due to the varied ABA response to temperature. High VPD decreased leaf water potential, leaf area, and DMshoot, which exacerbated the inhibition of soil drying to plant growth. Across the well-watered plants in both experiments, negative linear relationships of gs and WUE to VPD and positive linear relations between Tr and VPD were found. The results provide some novel information for developing mechanistic models simulating crop WUE and improving irrigation scheduling in future arid climates.

20.
Polymers (Basel) ; 14(19)2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36236028

RESUMEN

Surface treatment technology is an effective method to reinforce the durability of concrete. In this study, cement-based materials containing industrial solid wastes were modified by hybrid nano-silica (HN), then applied as a novel surface protection material (SPM-HN). The effect of SPM-HN on surface hardness of mortar matrix exposed to seawater was investigated. Further, the microstructure was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and mercury intrusion porosimetry (MIP). The results show SPM-HN could significantly enhance the surface hardness of matrix in seawater curing, and the rebound number is increased by 94%.The microstructure analysis demonstrates that the incorporation of HN inhibits the formation of ettringite, thaumasite, and Friedel's salt. In addition, thermodynamic modeling shows the incorporation of hybrid nano-silica could generate more C-S-H, and decrease the maximum volume of Friedel's salt when SPM is exposed to seawater. This research indicates SPM-HN can be applied as a concrete protective layer in the marine environment.

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